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Phytogeocoenoses of the coastal western Hemlock zone in Strathcona Provincial Park, British Columbia,… Kojima, Satoru 1971

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PHYTOGEOCOENOSES OF THE COASTAL WESTERN HEMLOCK ZONE IN STRATHCONA PROVINCIAL PARK, BRITISH COLUMBIA, CANADA by SATORU KOJIMA. B.S.A., Hokkaido University, i960 M.S.A., Hokkaido University, 1962 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY In the Department of Botany We accept this thesis as^conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA December, 1971 In presenting t h i s thesis i n p a r t i a l f u l f i l m e n t of the requirements for an advanced degree at the University of B r i t i s h Columbia, I agree that the Library s h a l l make i t f r e e l y available f o r reference and study. I further agree that permission fo r extensive copying of t h i s thesis fo r s c h o l a r l y purposes may be granted by the Head of my Department or by h i s representatives. It i s understood that copying or p u b l i c a t i o n of t h i s thesis for f i n a n c i a l gain s h a l l not be allowed without my written permission. Department of Botany The University of B r i t i s h Columbia Vancouver 8, Canada Date December 20, 1971 i Abstract A vegetation-environmental relationships study, based on the concept and approach of biogeoclimatology established and developed by Krajina and his students, was conducted i n Strathcona Provincial Park, B r i t i s h Columbia, where the vegetation showed special ecosystematic pecu-l i a r i t i e s r e s u l t i n g from a unique geological substratum. The purposes of the present study were, therefore, 1) to c l a s -•i s i f y the vegetation i n the park according to the methods of the Zurich -Montpellier school as modified by Krajina, 2 ) to analyze as many environ-mental factors as possible, 3 ) to correlate the environmental factors with the plant communities at the association l e v e l , and 4) to discover the factors that contribute conspicuously to the development of the vegetation u n i t s . A t o t a l of ninety-nine plots were established to represent the phytogeocoenoses. These plots were l a t e r grouped into associations ac-cording to t h e i r f l o r i s t i c homogeneity and environmental s i m i l a r i t y . In the study area, four orders, eight a l l i a n c e s and eight as-sociations with three variants were established and described. In order to obtain general information concerning climate i n the study area, three weather stations and ten r a i n gauges were i n s t a l l e d and maintained for the summers of 1968 and 1969. Several pebbles were i d e n t i f i e d from each pl o t . They were found to be predominantly basalt and i t s a l l i e s , and the whole area was geologically f a i r l y homogeneous. A t o t a l of 377 s o i l samples were analyzed f o r physical and i i chemical properties such as s o i l texture, f i e l d moisture, f i e l d capacity, cation exchange capacity, exchangeable cations (Ca, Mg, Na and K), t o t a l nitrogen, carbon content, available phosphorus, and pH. Some selected samples were analyzed f o r i r o n and aluminum. S o i l s were generally coarse i n texture; most of the s o i l s were found to be loamy sand while some were sand and sandy loam. They were especially high i n base status, r e f l e c t i n g the influences of the base-rich parent material. Thus, most of the s o i l s examined were found to be Brunisols which were equivalent to "pararendzina" s o i l s (sensu Kubiena 1953)* In spite of high p r e c i p i t a t i o n , Podzols were rather rare. To the environmental factors which had been measured and e s t i -mated quantitatively, one way analysis of variance was applied to detect s i g n i f i c a n t differences among the f i v e forested associations. Of twenty-two factors taken into consideration, fourteen factors were found to be si g n i f i c a n t at the 1% l e v e l , one factor at the 5% l e v e l , and seven factors were not s i g n i f i c a n t . Duncan's new multiple range test was applied to the factors which were s i g n i f i c a n t either at the 1% or 5% l e v e l , and the associations were grouped and ranked using the r e s u l t of t h i s t e s t . The factors most i n f l u e n t i a l on the development of the associ-ations were selected by the multiple regression analysis. The twenty-two factors were treated as independent variables, while vegetation was processed as a dependent variable. In order to quantify the vegetation, " l i k e l i n e s s value" was devised and used. I t i s a numerical assessment si g n i f y i n g how l i k e l y a plot i s to be a member of a certain association, based on the species significance of some selected species. i i i A species constellation involving f i f t y - f i v e species was con-structed based on the Chi-square test and Cole's indices. Three assem-b l i e s of species were detected, which characterized 1) xeric and mesic habitats of the d r i e r subzone (CWHa) as well as xeric habitats of the wetter subzone (CWHb), 2) seepage habitats of both subzones, and 3) mesic habitats of the wetter subzone. In conclusion, i t became apparent that the uniqueness and com-p l e x i t i e s of the vegetation i n the study area rested i n the considerable intermingling of species of quite di f f e r e n t ecological character r e s u l t i n g from the high base status of the s o i l s . Because of base r i c h edaphic conditions, some of the c a l c i p h i l e s commonly occur free from t h e i r normally hygrotopic r e s t r i c t i o n . At the same time, a considerable number of acido-philes grow on humus, supported by the mor humus which i s already very acid due to the strong leaching by r a i n water. This kind of double struc-ture makes the vegetation p a r t i c u l a r l y complex and consequently more d i f f i c u l t to understand. Such an understanding, however, has been made possible, using the procedures followed i n the present thesis. iv CONTENTS Page I. Introduction 1 1. Objectives 1 2 . A b r i e f h i s t o r y of the studies on the vegetation of B r i t i s h Columbia 2 3 . Ecosystem concept 5 4. Approach adopted 7 5 . Selection of the study area 8 I I . General Description of Study Area 9 1 . General statement 9 2 . Geography and physiography / 9 3 . Geology 1 1 4. Climate 12 5 . S o i l s 1 6 i . Zonality concept 1 6 i i . S o i l s related to the study area 1 7 6 . Vegetation 2 2 i . The Coastal Western Hemlock Zone 2 2 i i . Palynological consideration on the development of vegetation after the g l a c i a t i o n 24 i i i . Vegetation i n the study area 2 6 I I I . Vegetation Analysis and Synthesis 3 6 1 . Methods for vegetation analysis 3 6 i . Premise 3 6 i i . Selection of plots 3 6 I i i . Plot size 3 7 i v . A n a l y t i c a l procedure 3 7 V 2. Methods for vegetation synthesis 40 3. Association concept 42 4. Higher and lower units for vegetation classification, 43 IV. Environmental Analysis 45 1. Climate 45 2. Light intensity 51 3. Rock identification 55 4. S o i l analysis 57 i , Texture 57 i i . F i e l d moisture 57 i i i . F ield capacity 58 iv. Hydrogen-ion activity (pH) 58 v. Exchangeable cations 58 v i . Other chemical properties 58 V. Description of Phytogeocoenoses 59 1. Pseudotsugetalia menziesii 62 1) Festuco (Occidentalls) - Juniperion communis montanae 6,3 (1) Hylocamio (splendentis) - Festuco (Occidentalls) - Juniperetum communis montanae 63 2) Gaultherion shallonis 68 (2) Hylocomio (splendentis) - Eurhynchio (oregani) -Gaultherio (shallonis) - Pseudotsugetum menziesii 68 2. Tsugetalia heterophyllae 77 3) Hylocomio (splendentis) - Pseudotsugo (menziesii) -Tsugion heterophyllae 78 (3) Hylocomio (splendentis) - Eurhynchio (oregani) -Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae 78 v i 4) Vaccinio (alaskaensis) - Abieto (amabilis) .-Tsugion heterophyllae 91 (4) Rhytidiadelpho ( l o r e i ) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae 91 3. Thujetalia plicatae 102 5) Mahonio (nervosae) - Polystichion muniti 103 (5) Eurhynchio (oregani) - T i a r e l l o ( t r i f o l i a t a e ) -Polysticho (muniti) - Achlydo ( t r i p h y l l a e ) -Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae 103 6) Oplopanacion h o r r i d i 121 (6) Plagiomnio (insignis) - Leucolepido (menziesii) - Adianto (pedati) - Oplopanaco (horridi) -Thujetum plicatae 121 7) L y s i c h i t i o n americani 131 (7) Sphagno (girgensohnii) - Rhizomnio (perssonii) - Lysichitetum americani 131 4. Spiraeo - M y r i c e t a l i a g a l i s 139 8) Spiraeo (douglasii) - Myricion g a l i s 139 (8) Campylio (polygami) - Carico (sitchensis) -Spiraeo (douglasii) - Myricetum g a l i s 139 VI. Vegetation and Environment Relationships 146 1. Topographic sequence of the associations 146 i . The d r i e r subzone 146 i i . The wetter subzone 149 2. Relationships between associations and environmental factors 151 A. Sequence and responces of the associations to the environmental factors 154 v i i 1) Light intensity 157 2) pH of humus 158 3) pH of the C horizon l 6 l k) F i e l d moisture 163 5) F i e l d capacity 165 6) Sand 169 7) S i l t 170 8) Clay 171 9) Cation exchange capacity of humus Ijh 10) Cation exchange capacity of mineral soils 175 11) Calcium 176 12) Magnesium 178 13) Sodium 181 lk) Potassium 182 15) Organic matter 183 16) Nitrogen 188 17) Available phosphorus 19k 18) Slope 196 19) Carbon-nitrogen ratio of humus 199 20) Carbon-nitrogen ratio of mineral soils 201 21) Base saturation of humus 202 22) Base saturation of mineral soils 206 B. The most influential factors upon the development of the associations 208 i . Multiple regression analysis 209 i i . "Liveliness value" as dependent variables 211 i i i . The selected multiple regression equations 215 iv. Interpretation of the selected multiple regression equations 217 v i i i 3. Relationships among the associations 223 4. Interspecif ic association and species constellation 226 i . Interspecif ic association 226 i i . Assessment of the degree of association 228 i i i . Species constellation 232 VII. S o i l and Vegetation Development 236 VIII. Summary and Conclusion 245 IX. Bibliography 254 Appendices 271 ix LIST OF TABLES Table Page 1 Temperature and precipitation at Strathcona Dam site 15 2 A community structure of Arbutus menziesii stand 33 3 Species significance scale 39 4 Sociability scale 39 5 Presence and constance class 40 6 A general synopsis of a hierarchy 60 7 Characteristic combinations of species for the orders and alliances 6 l 8 Association table of Hylocomio (splendentis) - Festuco (Occidentalis) - Juniperetum communis montanae 64 9 General environment in Hylocomio (splendentis) - Festuco (Occidentalis) - Juniperetum communis montanae 65 10 General characteristics of soils in Hylocomio (splendentis) - Festuco (occidentalis) - Juniperetum communis montanae 66 11. Association table of Hylocomio (splendentis) - Eurhynchio (oregani) - Gaultherio (shallonis) - Pseudotsugetum menziesii 69 12 General environment in Hylocomio (splendentis) - Eurhynchio (oregani) - Gaultherio (shallonis) - Pseudotsugetum menziesii 70 13 General characteristics of soils in Hylocomio (splendentis) - Eurhynchio (oregani) - Gaultherio (shallonis) - Pseudo-tsugetum menziesii 71 14 Association table of Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae 79 X 15a G e n e r a l environment i n Hylocomio ( s p l e n d e n t i s ) - E u r h y n c h i o (oregani ) - Mahonio (nervosae) - Pseudotsugo - Tsugetum h e t e r o p h y l l a e mahoniosum nervosae 80 15b G e n e r a l environment i n Hylocomio ( s p l e n d e n t i s ) - E u r h y n c h i o (oregani ) - Mahonio (nervosae) - Pseudotsugo - Tsugetum h e t e r o p h y l l a e hylocomiosum s p l e n d e n t i s 8l 16 G e n e r a l c h a r a c t e r i s t i c s of s o i l s i n Hylocomio ( s p l e n d e n t i s ) - E u r h y n c h i o (oregani ) - Mahonio (nervosae) - Pseudotsugo - Tsugetum h e t e r o p h y l l a e 82 17 A s s o c i a t i o n t a b l e o f R h y t i d i a d e l p h o ( l o r e i ) - P l a g i o t h e c i o ( u n d u l a t i ) - Rubo ( p e d a t i ) - V a c c i n i o ( a l a s k a e n s i s ) -A b i e t o ( a m a b i l i s ) - Tsugetum h e t e r o p h y l l a e °2 18 G e n e r a l environment i n R h y t i d i a d e l p h o ( l o r e i ) - P l a g i o -t h e c i o ( u n d u l a t i ) - Rubo ( p e d a t i ) - V a c c i n i o ( a l a s k a e n s i s ) - A b i e t o ( a m a b i l i s ) - Tsugetum h e t e r o p h y l l a e 93 19 G e n e r a l c h a r a c t e r i s t i c s o f s o i l s i n R h y t i d i a d e l p h o ( l o r e i ) - P l a g i o t h e c i o ( u n d u l a t i ) - Rubo ( p e d a t i ) - V a c c i n i o ( a l a s k a e n s i s ) - A b i e t o ( a m a b i l i s ) - Tsugetum h e t e r o p h y l l a e 9^ 20 A s s o c i a t i o n t a b l e o f Eurhynchio (oregani ) - T i a r e l l o ( t r i f o l i a t a e ) - P o l y s t i c h o ( m u n i t i ) - Ach lydo ( t r i p h y l l a e ) - Pseudotsugo - Tsugo ( h e t e r o p h y l l a e ) - Thujetum p l i c a t a e 104 21a G e n e r a l environment i n Eurhynchio (oregani ) - T i a r e l l o ( t r i f o l i a t a e ) - P o l y s t i c h o ( m u n i t i ) - Ach lydo ( t r i p h y l l a e ) - Pseudotsugo - Tsugo ( h e t e r o p h y l l a e ) - Thujetum p l i c a t a e achlydosum t r i p h y l l a e 105 21b G e n e r a l environment i n E u r h y n c h i o (oregani ) - T i a r e l l o ( t r i f o l i a t a e ) - P o l y s t i c h o ( m u n i t i ) - Ach lydo ( t r i p h y l l a e ) - Pseudotsugo - Tsugo ( h e t e r o p h y l l a e ) - Thujetum p l i c a t a e gymnocarpiosum d r y o p t e r i d i s 106 21c G e n e r a l environment i n E u r h y n c h i o (oregani ) - T i a r e l l o ( t r i f o l i a t a e ) - P o l y s t i c h o ( m u n i t i ) - A c h l y d o ( t r i p h y l l a e ) - Pseudotsugo - Tsugo ( h e t e r o p h y l l a e ) - Thujetum p l i c a t a e p o l y s t i c h o s u m m u n i t i 107 22 G e n e r a l c h a r a c t e r i s t i c s o f s o i l s i n Eurhynchio (oregani ) - T i a r e l l o ( t r i f o l i a t a e ) - P o l y s t i c h o ( m u n i t i ) - A c h l y d o ( t r i p h y l l a e ) - Pseudotsugo - Tsugo ( h e t e r o p h y l l a e ) -Thujetum p l i c a t a e 108 x i 23 Association table of Plagiomnio (insignis) - Leucolepido (menziesii) - Adianto (pedati) - Oplopanaco (horridi) -Thujetum plicatae 122 24 General environment i n Plagiomnio (insignis) - Leucolepido (menziesii) - Adianto (pedati) - Oplopanaco (horridi) -Thujetum plicatae 123 25 General characteristics of s o i l s i n Plagiomnio (insignis) - Leucolepido (menziesii) - Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae 124 26 Association table of Sphagno (girgensohnii) - Rhizomnio (perssonii) - Lysichitetum americani 132 27 General environment i n Sphagno (girgensohnii) - Rhizomnio (perssonii) - Lysichitetum americani 133 28 General characteristics of s o i l s i n Sphagno (girgensohnii) - Rhizomnio (perssonii) - Lysichitetum americani 134 29 Association table of Campylio (polygami) - Carico (sitchensis) - Spiraeo (douglasii) - Myricetum g a l i s 141 30 General environment i n Campylio (polygami) - Carico (sitchensis) - Spiraeo (douglasii) - Myricetum g a l i s 142 31 General characteristics of s o i l s i n Campylio (polygami) -Carico (sitchensis) - Spiraeo (douglasii) - Myricetum g a l i s 143 32 Environmental factors taken into the s t a t i s t i c a l treatment 152 33 Correlation matrix for twenty-two factors 155 34 Comparison of base saturation 204 35 The selected multiple regression equations 2l6 36 Correlation matrix between associations 223 37 Correlation matrix for f i f t y - f i v e species based on Cole's index 231 38 Comparison of base 3tatus of s o i l s 237 x i i LIST OF FIGURES Figure Page 1 Map of the study area 10 2 Climatic change from west to east 14 3 General view of the study area (Wolf River Valley) 27 4 General view of the study area (Buttle Lake) 27 5 Wolf River Valley forest 30 6 A well developed corticolous community 30 7 A stand of Arbutus menziesii 32 8 A stand of Arbutus menziesii 32 9 Weather station No.l 45 10 Location of weather stations and rain gauges 46 11 Daily temperature and minimum humidity during summer of 1968 47 12 Daily temperature and minimum humidity during summer of 1969 48 13 Daily cyclic pattern of temperature 50 14 Hylocomio (splendentis) - Festuco (occidentalis) -Juniperetum communis montanse 15 Hylocomio (splendentis) - Festuco (occidentalis) -Juniperetum communis montanae 67 16 Hylocomio (splendentis) - Eurhynchio (oregani) -Gaultherio (shallonis) - Pseudotsugetum menziesii 72 17 Hylocomio (splendentis) - Eurhynchio (oregani) -Gaultherio (shallonis) - Pseudotsugetum menziesii 73 x i i i 18 Hylocomio (splendentis) - Eurhynchio (oregani) -Gaultherio (shallonis) - Pseudotsugetum menziesii 73 19 Hylocomio (splendentis) - Eurhynchio (oregani) -Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae 83 20 A t y p i c a l s o i l p r o f i l e i n Hylocomio (splendentis) -Eurhynchio (oregani) - Mahonio (nervosae) - Pseudo-tsugo - Tsugetum heterophyllae 87 21 Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae mahoniosum nervosae 89 22 Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae hylocomiosum splendentis 89 23 Rhytidiadelpho ( l o r e i ) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae 95 24 Rhytidiadelpho ( l o r e i ) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae 95 25 Vaccinium alaskaense 99 26 Streptopus streptopoides 99 27 The best growth of Pseudotsuga menziesii i n Eurhynchio (oregani) - T i a r e l l o ( t r i f o l i a t a e ) - Polysticho (muniti) - Achlydo (t r i p h y l l a e ) - Pseudotsugo - Tsugo (hetero-phyllae) - Thujetum plicatae 109 28 Eurhynchio (oregani) - T i a r e l l o ( t r i f o l i a t a e ) -Polysticho (muniti) - Achlydo (triphy l l a e ) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae achlydosum t r i p h y l l a e 114 29 Eurhynchio (oregani) - T i a r e l l o ( t r i f o l i a t a e ) -Polysticho (muniti) - Achlydo (t r i p h y l l a e ) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae gymnocarpiosum dryopteridis 114 30 Eurhynchio (oregani) - T i a r e l l o ( t r i f o l i a t a e ) -Polysticho (muniti) - Achlydo ( t r i p h y l l a e ) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum. plicatae polystichosum muniti 116 xiv 31 Eurhynchio (oregani) - T i a r e l l o ( t r i f o l i a t a e ) -Polysticho (muniti) - Achlydo (triph y l l a e ) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae 116 32 Excellent growth of Pseudotsuga menziesii 119 33 Plagiomnio (insignis) - Leucolepido (menziesii) -Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae 125 34 Plagiomnio (insignis) - Leucolepido (menziesii) -Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae 125 35 Oplopanax horridus and Adiantum pedatum 129 36 A s o i l p r o f i l e i n Plagiomnio (insignis) - Leucolepido (menziesii) - Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae 129 37 Sphagno (girgensohnii) - Rhizomnio (perssonii) -Lysichitetum americani 135 38 Sphagno (girgensohnii) - Rhizomnio (perssonii) -Lysichitetum americani 135 39 General view of Drum Lakes 144 40 Campylio (polygami) - Carico (sitchensis) - Spiraeo (douglasii) - Myricetum g a l i s 14-4 Ul Topographic sequence of associations under humid climate 147 42 Topographic sequence of associations under perhumid climate 148 43 S o i l reactions (pH) of different horizons i n the associations 160 44 Regression l i n e s between f i e l d capacity and f i e l d moisture 168 45 A dendrogram, showing a f f i n i t i e s among the associations 224 46* A species constellation based on Cole's index 233 X V Acknowledgement I should l i k e to express many thanks to many persons from whom I have received considerable support, both physical and s p i r i t u a l , during the course of th i s work. F i r s t , I would l i k e to express my sincere gratitude t o Dr. V.J. Kraj i n a , my research supervisor, for his academic inst r u c t i o n and guidance, warm encouragement, and f i n a n c i a l support; without these the present study could never have been accomplished. Dr. Krajina also determined most of the bryophytes and some of the vascular plants. I am also very much indebted to the members of my research commit-tee, Drs. G.H.N. Towers, W.B. Schofield, K.I. Beamish ( a l l of the Department of Botany), and L.M. Lavkulich (of the Department of S o i l Science) for t h e i r h e l p f u l advice and revision of the t e x t , especially to Dr. Schofield for his patience i n improving the manuscript. Many thanks to Drs. R.C. Brooke (of the Department of B i o l o g i c a l Sciences, Simon Fraser University) and CE. B e i l (of the Department of Botany, University of B r i t i s h Columbia) for t h e i r kind suggestions and useful comments, to Mr. G. Otto for his i d e n t i f i c a t i o n of most of the lichens. My thanks to my colleagues R. Revel and R. Annas f o r useful d i s -cussions throughout the progress of t h i s work. Special thanks are due to Mrs. J . Svobodova for her patience i n typewriting the cumbersome vegetation synthesis tables. x v i I must also express my indebtedness to the University of B r i t i s h Columbia for the award of a Graduate Fellowship, and to the National Research Council of Canada for support of the present study through Grant No. A-92 awarded to Dr. V.J. Krajina. 1 I. Introduction 1. Objectives Strathcona Provincial Park, which is located in the central part of Vancouver Island, British Columbia, has an interesting uniqueness in i t s vegetation, namely, despite the fact that the whole area of the park belongs macroclimatically to the Coastal Western Hemlock Zone (Krajina 1959b» 1965a, 1969) , the vegetation shows close a f f i n i t i e s to that of the Coastal Douglas-f i r Zone, especially to the wetter subzone (McMinn 1957, i960) , rather than to that of the Coastal Western Hemlock Zone (Orloci 196l, 1964). Thus, most of the forests in the park consist predominantly of Douglas-fir (Pseudotsuga  menziesii) which thrives vigorously. In the lesser vegetation, a similar tendency is also common. This peculiarity in the vegetation results from the unique edaphic conditions which have been caused by pararendzina soils (Kubiena 1953) derived from base-rich parent material. Should the factorial equation (Jenny 1941, 196l) be followed, this is the case where the factor P (parent material) contributes eminently to the status of the equation, yielding unique soils and concomitant vegetation. The purposes of the present study are l) to classify the vegeta-tion of Strathcona Provincial Park, based on the classification system of the Zurich - Montpellier School, modified by Krajina, 2) to analyse as many environmental factors as possible, both quantitatively and qualitatively, 3) to correlate the environmental factors with plant communities (at the association level), 4) to discover the factors contributing to the development of the vegetation, and 5) to elucidate the cause of the aforementioned unique-ness in the vegetation. 2 2. A brief history of the studies on the vegetation of British Columbia The vegetation of British Columbia was studied by Whitford and Craig as early as 1918 in connection with the forest inventory. They divided British Columbia into five belts based on climo-orographic conditions. In each belt, they recognized several forest types, regarding them as products of macroclimate. Each forest type was further subdivided into subtypes, resulting mainly from different s o i l conditions within the area. Therefore, their classification system was entirely environmental, and the forest type was equivalent to the formation in the sense of Clements (1916, Weaver and Clements 1938), and subtype to association (sensu Clements ibid.). Concerning the coastal area of British Columbia (west of the Coast Mountains and Cascade Mountains), Douglas-fir - Red Cedar type, Red Cedar - Hemlock type, Western Hemlock - Sitka Spruce type, Western Hemlock - Amabilis F i r type and Sub-alpine and Muskeg types were recognized. Halliday (1937) investigated the forests of Canada and classified the vegetation of British Columbia into five regions which were further subdivided into sections, also considering a region as a product of climate. His classification system was, however, so geographically biased that each category was rather heterogeneous in the vegetational aspects. In the coastal area, he described the Madrono-Oak section, South Coast section, Central Coast section and North Coast section. Clements (Weaver and Clements 1938) divided Br i t i s h Columbia into four formations based on climax vegeta-tion, regarding i t as a direct expression of climate. Thus, his approach was also entirely environmental. In the coastal area, he recognized Thuja - Tsuga association. Meanwhile, a Fenno-Scandinavian student Ilvessalo (1929) surveyed some of the vegetation of North America and reported brief notes in which he described 3 ten forest types based on the forest typological approach which was esta-blished by Cajander (1909» 1926, 1949). A more elaborate study on the North American vegetation was carried out later by another Fenno-Scandinavian student, Kujala (1945), who described a number of forest types based on the dominants in the lesser vegetation (shrub, herb and moss layer), following a s t r i c t l y typological approach. Out of these forest types, Gaultheria type. Vaccinium parvifolium type, T i a r e l l a - Vaccinium parvifolium type, Achlys - T i a r e l l a - Aspidium munitum type, Achlys - Gaultheria type, T i a r e l l a -Aspidium munitum type and Lysichiton type were described for the coastal area of British Columbia. Thus, both Kujala's and Ilvessalo's approaches were entirely phytocoenological. Spilsbury and Smith (1947) investigated the second growth Douglas-f i r stands in south-east Vancouver Island, lower Fraser Valley, and some parts of western Washington and Oregon, and they described five forest site types based on the f l o r i s t i c structure, regarding the forest type as a sub-division of the "climax vegetation" (Weaver and Clements 1938). Their forest site types are Polystichum - Gaultheria type, Gaultheria type, Polystichum type, Gaultheria - Parmelia type, and Gaultheria - Usnea type. Although Rowe (1959) described the forest regions in Canada, this was merely a refinement of Halliday's work (1937). He s t r i c t l y followed the Halliday's system and divided Southern Coast section (Halliday 1937) into South Pacific Coast section and Coastal Subalpine section. In the studies of vegetation of British Columbia, the Fenno - Scan-dinavian tradition reappeared with Hamet-Ahti's work (1965). Basically following the forest typological approach, she took the environmental aspects into consideration in addition to the phytocoenological framework, and attempted to classify the vegetation of British Columbia at the zonal lev e l . Neverthe-4 l e s s , her environmental consideration was rather climo-orographically biased* and edaphic factors were not taken much in t o account. Thus, her approach was somewhat ecosystematic but not e n t i r e l y holocoenotic. Concerning the c o a s t a l area of B r i t i s h Columbia, she recognized the following vegetation zones: l ) orohemiarctic (AT)*; 2) upper oroboreal (MHb); 3) lower oro-boreal (MHa); 4) humid hemiboreal (CWH); 5) humid boreomeridional (CDFb); 6) summer dry boreomeridional (CDFa). Knapp (1965) described the vegetation of North America mainly from the physiognomical point of view. K r a j i n a (1959b, 1965a, 1969) proposed a somewhat o r i g i n a l zonal c l a s s i f i c a t i o n system of the vegetation of B r i t i s h Columbia based on the biogeoclimatological approach, d i v i d i n g B r i t i s h Columbia i n t o eleven biogeo-c l i m a t i c zones. Since t h i s approach i s fundamental to the present discus-s i o n , i t i s appropriate to describe h i s concept i n some d e t a i l . P h i l o s o p h i c a l l y , h i s c l a s s i f i c a t i o n system i s based on the theorem which was or i g i n a t e d by Dokuchaev (1899) and l a t e r elaborated by Jenny (1941, 196l) and Major (1951), that i s , vegetation as w e l l as s o i l s i s a f a c t o r i a l product of climate, parent m a t e r i a l , topography, organisms and time. I t i s an i n t e g r a t i o n of three d i f f e r e n t approaches, i . e . l ) the zonal approach represented by Clements i n North America, 2) phytocoenological approach r e -presented by Braun-Blanquet i n the Zurich - Montpellier school, and 3) topo-l o g i c a l approach represented by Pogrebniak i n the Ukrainian school. There-f o r e , i t i s e n t i r e l y ecosystematic (holocoenotic). As a b a s i c u n i t , biogeo-cl i m a t i c zone i s employed, which may be divided i n t o subzones. Each zone i s characterized by three d i f f e r e n t aspects, i . e . macroclimate, zonal s o i l and * Symbols i n parentheses are the abbreviations of comparable biogeoclimatic zones (Krajina 1959b, 1965a, 1969)1 where AT: Alpine Tundra zone; CDFa: Coastal Douglas-fir zone, d r i e r subzone; CDFb: Coastal Douglas-fir zone, wetter subzone; CWH: Coastal Western Hemlock zone; MHa: Mountain Hemlock zone, lower subzone; MHb: Mountain Hemlock zone, upper subzone. 5 climatic climax community which develops on a mesic habitat. Therefore, the most characteristic habitat of the zone is represented by a mesic habitat. The association (sensu Braun-Blanquet 1 9 2 1 , 1 9 3 2 , modified by Krajina i 9 6 0 ) is used to describe ecosystem (Tansley 1935) or biogeocoenoses (Sukachev 1 9 4 5 ) , which is ecosystematic by a modified definition (Krajina i 9 6 0 ) . The nomenclature of the zone is based on the name of the plants which can perpe-tuate in the climatic climax communities. These plants must be shade tolerant on mesic habitats of that zone and must self-regenerate under their own canopy. A biogeocoenosis which belongs to a certain biogeoclimatic zone may appear in other biogeoclimatic zones, but usually under some other r e l i e f . The biogeoclimatic zones are grouped into the higher zonal unit, biogeoclim-atic region, and regions are put together into a biogeoclimatic formation. In British Columbia, four formations and seven regions have been recognized (Krajina 195S*>i 1 9 6 5 a , 1969). Under the biogeoclimatological framework, intensive studies have been and are s t i l l being carried out by Krajina and his students (see Krajina 1 9 6 9 ) . This study attempts to contribute to this series. 3 . Ecosystem concept A forest is a highly complex ecosystem which remains at or appro-aches dynamic equilibrium, and in which a l l the components (plants, animals, micro-organisms and non-living substances) closely interact, forming insepar-able "web-like" inter-relations. An attempt to understand nature as a holocoenotic entity can be traced early in this century in Morozov's concept of silviculture. In his textbook ( 1 9 2 7 ) , he stated that a forest i s a complicated organism in which 6 a l l parts possess definite relations and which has a specific distinctness just like every organism (from Zonn 1954). Prior to him, Mobius (l8TT) described an oyster bed as a "biocoenose" in which a l l organisms were closely tied up together under the influences of a more or less similar environment. Several terms with similar connotation were proposed: "microcosm" (Forbes 1887), "holocoen" (Frederichs 1927), "biotic community" (Phillips 1931), "bio-system (Thieneman 1939). Tansley (1935) proposed the term "ecosystm" which has been widely accepted particularly in the western world, defining i t as " the systems which are the basic units of nature o f t h e face of the earth, and in which there is constant interchange of the most various kinds within each system, not only between organisms but between the organic and inorganic. Ecosystems are of the most various kinds and size. They form one category of the multitudinous physical systems of the universe, which range from the universe as a whole down to the atom". of Morozov's concept resulted in the addition of another new term "biogeo-coenose" by Sukachev (1945, Sukachev and Dylis 1964), Biogeocoenose can be defined as a fragment of the earth's surface where a definite type of inter-action exists between biocoenose and i t s counterparts, i.e. atomosphere, lithosphere, hydrosphere and pedosphere. A functional structure of a bio-geocoenose which is more elaborate is diagramatically shown in Sukachev's textbook (sukachev and Dylis 1964). 11 Meanwhile, in Russia, the inheritance and the further development Biocoenose Phytogeocoenose Zobcoenose Microbocoenose Biogeocoenose L — E cot ope Climotope Edaphotope 7 Sukachev (l°60a) discussed the difference between ecosystem and biogeocoenose as follows: the former is a system which is applicable to any rank of objects from a single atom up to the whole universe and within i t a l l components are interacting and controlled by physico-chemical laws, while the latter is a quite definite object of study and i t cannot be con-sidered as a general term for a l l taxonomic subdivisions of the biogeocoe-notical cover on the earth. According to Major (1969), ecosystem is inter-preted as systems, rather physico-chemical system, which are to be analysed by mathematical means, on the other hand, a biogeocoenose is more descriptive. The writer interprets the ecosystem as an abstract and ideological product which embraces any kind and size of nature from a single atom up to the whole universe, whereas, a biogeocoenose i s a concrete entity which can be described as a part of nature in which organic and inorganic components are closely related. A biogeocoenose represents a certain habitat which i s manifested by a certain biocoenose (Krajina 1971, personal communication). A phytogeocoenose (Krajina and his students) is the vegetational part of the biogeocoenose (Sukachev). 4. Approach adopted In the present study, the ecosystematic approach (Krajina i960) based on the biogeoclimatology established by Krajina has been adopted, namely, an equal emphasis was placed on the environmental characters as well as vegetation in order to classify and describe the vegetation. Vege-tation, here, is regarded as a concrete expression of the biogeocoenoses (sensu Sukachev 1945) which can be recognized, can be described and can be treated as an object of study. The association (sensu Braun-Blanquet 1921, 1932, modified by Krajina i960) was employed as the basic unit which may 8 unify the closely related biogeocoenoses (sensu Sukachev). A plot is a sampling unit which is actually established in the f i e l d , and from which various kinds of information concerning the vegetation as well as environ-ment are obtained. Moreover, a plot is regarded as an "association i n d i v i -duum" (Braun-Blanquet 1932) which is comparable to a biogeocoenosis. Sampling sites were subjectively determined. This is not only more practi-cal than random sampling which requires more time and expense, but is also more effective in selecting suitable sites, avoiding heterogeneous sites, transitions and ecotones. 5 . Selection of the study area In order to find a suitable location for this study, two prelimi-nary survey trips were carried out under the direction of Dr. Krajina. The f i r s t t r i p was conducted in September, 1967, mainly in the Upper Campbell Lake area, Buttle Lake area, and Gold River area. A second t r i p was taken in May, 1968, mainly in Puntledge River Valley area and partly in the Upper Campbell Lake area. As a result of these the northern and central parts of Strathcona Provincial Park, including the Upper Campbell Lake area, Buttle Lake area, Elk River Valley area, Heber River Valley area, and Wolf River Valley area, were selected as the study area because of i t s diversity in phytogeocoenoses. 9 II. General Description of Study Area 1. General statement Because this study is concerned primarily with the phytogeocoe-noses of the coastal western hemlock zone in Strathcona Provincial Park, i t is intensively focused upon the low altitudinal areas (submontane and montane). The northern and central parts of the park, which include the Buttle Lake area, Wolf River Valley area were selected as the study area, due to the diversity of phytogeocoenoses and the accessibility for conducting the study. 2. Geography and Physiography Strathcona Provincial Park, covering approximately 2090 square k i l o -metres, is located in the central part of Vancouver Island (Figure l ) . L a t i -tudinally, i t l i e s between U9°30' - 50°00'N and longitudinally 125°15' - 126° 00*W. The nearest city to the east is Campbell River, about forty-eight kilometres from a bridge which l i e s between Upper Campbell Lake and Buttle Lake, and to the west is Gold River, about forty-two kilometres from the bridge. A highway (No. 19) passes through the northern part of the park, connecting these two c i t i e s . There are several other privately owned roads which lead to logging operation sites or mining excavation sites. Almost in the centre of the park, there are two relatively large lakes, Upper Campbell Lake and Buttle Lake, whose mean water level is 221m above sea l e v e l , the lowest ele-vation in the study area. As the park l i e s just on the "backbone ridges" of Vancouver Island, most of i t is essentially mountainous. There are a great number of peaks 11 which exceed 1500 m in elevation, including the highest peak (Golden Hinde 2 2 2 8 m) on Vancouver Island, According to Holland (196*0, these peaks compose a part of the Vancouver Island Ranges, which are included within the Insular. Mountains of the Western system. The Vancouver Island Ranges are generally composed of a heterogeneous group of pre-Cretaceous sedimentary and volcanic rocks folded about northwesterly-trending axes and intruded by numerous granitic batholiths. In the study area, the predominant mountain building activity resulted from massive volcanic activity during early Mesozoic eras (Surdam 1 9 6 8 ). Continued erosion during the Tertiary caused mature dissection of the mountains. Pre-Pleistocene u p l i f t and dissection of the surface produced an extremely rugged topography in the central and northern parts of the Island, where the u p l i f t was the greatest. This topo-graphy was modified by glaciation during the Pleistocene so that the high peaks were carved by alpine glaciers and the lowland by valley glaciers. In the Buttle Lake area, there is a noticeable set of north-south faults, one of which resulted in the establishment of the lake (Surdam ibid . ) . 3. Geology Most of the study area is covered by massive volcanic rocks which consist mainly of basalt, pillow basalt, pillow breccia, and volcanic breccia. The pillows average one foot in diameter and intrapillow spaces are f i l l e d with nests of quartz and serpentine (Muller 1 9 6 5 ) . According to Surdam ( 1 9 6 8 ) , these rocks are classified into the Karmutsen Group which is a part of the volcanic rich Mesozoic section, and they originated through the massive Triassic volcanic activity which corresponds to the Cordilleran eugeosyncline 12 in western British Columbia. The western region of Upper Campbell Lake and Buttle Lake was suggested to be a major source of volcanism at the time. One of the geological characteristics of the Karmutsen Group in central Van-couver Island is that i t is neither highly metamorphosed nor strongly folded. Surdam (1968) described seventeen lithologic units in the Buttle Lake area. The oldest rocks in the area, which are exposed in the Wolf River Valley, are the Palaeozoic volcanic flows (Sicker Group) which consist of andesitic to basaltic flows. The upper part of the Sicker Group consists of a limestone bed up to 300 metres in thickness, which is exposed on the east slope of Mt. Con Reid and along the west side of the south fork of Wolf River, and also on the south-eastern side of Buttle Lake. This limestone is in part crinoidal with chert nodules and contains fossils of Early Permian age. A prominent structural pattern of the area is numerous north-south faults, most of which are vertically cut. They delimit a series of fault blocks resulting in the regional outcrop patterns. k. Climate There is considerable d i f f i c u l t y in obtaining reliable meteorolo-gical information for the study area, because, within or close to i t , there is no weather station which provides a complete record with sufficient dura-tion of observations. A limited amount of climatic information is available from logging camps, the forest ranger station, and a mining company; how-ever, this is incomplete in that the observations are limited to a particular season, e.g. summer season, or they are lacking the data on either precipi-tation or temperature. The nearest weather station which has sufficient 13 duration of observation is located in Campbell River on the east coast of Vancouver Island. On the west coast, the weather station of Esteven Point provides complete meteorological information. Both of them, however, are so distant from the study area that they do not represent i t . A weather station at the Strathcona dam site ( 5 0 ° 0 0 ,N, 125°35'W), which has been maintained by B.C. Hydro Power Authority since 1 9 6 8 , provides useful information. Most parts of Vancouver Island except for high elevations are macroclimatically characterized by a £ climate (Ackerman 1 9 ^ 1 , Chapman 1 9 5 2 ) . According to Koppen's climatic classification system modified by Trewartha* (1957)» the climate is further subdivided into two sections, i.e. Csb and Cfb climates. The southern part of the Island belongs to the former category, where the annual total precipitation does not exceed 900 mm due to the rain shadow effect of the orographic situation, whereas the remainder of the Island belongs to the latter category, where annual total precipitation is much higher. Most of the western parts of the Island receive more than 2800 mm of annual total precipitation. The climate of Vancouver Island is predomi-nantly under the influence of the Pacific Ocean. In other words, i t is a mari-time climate which is characterized by: l ) mild temperature with prolonged cloudy periods and a small range of temperature; 2 ) wet, mild winters, cool relatively dry summers, and a long frost free season; and 3) heavy precipi-tation, most of which occurs during the winter season (Chapman 1 9 5 2 , Krajina 1959* Franklin and Dyrness 1 9 6 9 ) . These climatic features are more conspi-cuous on the west coast of the Island, which is called the Outer Coastal area * Trewartha i | ( l968) revised his climatic classification system, originally proposed by Koppen ( 1 9 3 6 ) . According to the new system, the whole area of Vancouver Island, except for high elevations, is categorized into Do climate (temperate oceanic climate) where the number of months with mean monthly temperature over 10°C is four to seven, and the mean monthly temperature of the coolest month is over 0°C. However, the present study follows the conven-tional previous climatic classification system. Precipitation (mm) -* ro o. Temperature § § § S Table 1. Temperature and P r e c i p i t a t i o n at the Strathcona Dam S i te To ta l Month JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC or Mean Temperature (°C) - 2 . 8 2.0 5.1 6.2 12.2 15.6 17.0 14.8 13.1 8.2 5.1 i . 2 8.2 P r e c i p i t a t i o n (am) 291 138 85 93 6 i 65 48 85 96 I83 197 2 6 l 1603 16 (Chapman 1 9 5 6 ) , and they decrease eastward across the Vancouver Island Mount-ains to the Inner Coastal area (Chapman ibid . ) . Figure 2 shows this trend in relation to r e l i e f . Most of the study area belongs to Cfb climate with annual t o t a l precipitation of at least 1520 mm, and i t may belong partly to Dfb climate depending upon local conditions. This is inferred from the meteorological data obtained from the Strathcona dam site (Table l ) , supported by the following facts that: l) the location of the dam site is outside the study area proper and i t is more leeward and closer to the east coast of Vancouver Island where the climate is generally drier, in winter cooler and in summer warmer, 2) the elevation of the site (150m a.s.l.) is lower than any place in the study area, and 3) the normal temperature is expected to be high enough to satisfy the conditions for -C climate. Though temperature seems too low to belong to £ climate, the data are based on only two years observations (1968 and 1969) and the winter of 1969 was exceptionally severe throughout British Columbia (temperature in January was 6 - 8°C below normal temperature in Vancouver Island area: from monthly record for 1 9 6 9 ) . 5 . Soils i . Zonality concept The zonality concept originated in Russia by Sibirtsev ( 1 8 9 8 ) as a result of a further development of Dokuchaev's theorem that the s o i l is a factorial product of climate, topography, parent material, organisms, and time. He cl a s s i f i e d soils into three categories especially stressing the importance of climate (humidity) and organisms (vegetation), i.e. l ) zonal s o i l s : soils which develop under the prevailing influences of climate and 17 organisms over a considerable period of time, equivalent to the Ectodynamo-morphic soils (Glinka 1914), 2) intrazonal s o i l s : soils which develop under the strong influences of parent material over climate, e.g. rendzina soils on limestone, pararendzina soils on basic volcanic rocks (Kubiena 1 9 5 3 ) , equivalnt to the Endodynamomorphic soils (Glinka 1914), 3) azonal soils: immature soils without enough differentiation of horizons due to a lack of enough time for s o i l formation, e.g. fresh a l l u v i a l deposits and fresh glacial residues, or due to highly resistant parent rocks to weathering. The zonal soils are comparative to the climatic climax or mesic plant associations in vegetation study, whereas the intrazonal soils correspond to the edaphic, xeric and hygric, climax communities. i i . Soils related to the study area Krajina ( 1 9 6 5 a , 1969) designated the zonal s o i l s , which develop on mesic habitats, in the coastal western hemlock zone as Humo-Ferric or Ferro-Humic Podzols in the drier subzone, and Humic Podzols in the wetter subzone. Podzols generally develop under the following circumstances: a cool, humid climate; some degree of through-moistening of the s o i l system; low content of strong bases in the plant residues; low rate of biocycling of elements, particularly in respect to Ca (Ponomareva 1 9 6 9 ) . In the coastal western hemlock zone, the heavy precipitation promotes a strong leaching of the s o i l s , and the relatively low temperature tends to accumulate a thick raw humus (mor*) layer which is biogenetically produced by prevailing activities of fungi rather than bacteria. This is the result of the preponderance of conif-erous l i t t e r in the forest floor which is more acid than that of angiosperm-* Mor: mycogeneous humus forms occurring in well drained to imperfectly drained conditions and consisting of unincorporated organic horizons; sharply delineated from the mineral s o i l , unless the latter has been blackened by the washing in of organic matter (NSSC S o i l Classification 1 9 6 8 ) . 18 cms trees (Ovington 1953), which provides advantageous conditions to fungi (Lutz and Chandler 1946). The strong percolation by r a i n water through the acid humus layer causes rapid downward movement of various substances from the surface horizon. The consequence of t h i s i s a development of eluviated horizon beneath the humus. Simultaneously the lower portion of the solum receives these eluviated substances. Most of the cations are washed out of the s o i l with water from p r e c i p i t a t i o n , but some of them, especially iron and aluminum, are concentrated i n the lower portion of the s o i l where they are combined with organic compounds i n the form of chelated compounds (Atkinson and Wright 1957) forming Bf, Bh, Bfh and Bhf horizons which are the characteristic horizons of the Podzols. There are no available s o i l data for the study area. However, i n the coastal western hemlock zone, Lesko (l96l) described s i x kinds of s o i l s (at the "order" l e v e l i n the Canadian S o i l C l a s s i f i c a t i o n System) including one subaqueous s o i l (sensu Kubiena 1 9 5 3 ) , and he recognized that lesser vege-tat i o n was the more sensitive indicator of s o i l conditions i . e . s o i l moisture regime as w e l l as chemical properties. McMinn ( 1 9 5 7 , I 9 6 0 ) studied the s o i l -vegetation relationships of the coastal Douglas-fir zone i n southeastern Vancouver Island and he found that the variation i n s o i l moisture regime was the most s i g n i f i c a n t factor i n s i t e d i f f e r e n t i a t i o n and d i s t r i b u t i o n . In a neighbouring area, Keser ( 1 9 6 9 ) studied the s o i l s i n Sayward Forest which i s located northwest of Campbell River on Vancouver Island. He described f i v e orders according to the Canadian S o i l C l a s s i f i c a t i o n System ( 1 9 7 0 ) and recognized that the concretions and iron pans which were noted i n Podzols and Brunisols were the prominent s o i l morphological features. P r i o r to t h i s , Krajina ( 1 9 6 4 , 1965a) had recognized weak l a t e r i z a t i o n and presence of concretions i n the d r i e r subzone of the coastal western hemlock zone and 19 in both subzone of the coastal Douglas-fir zone. According to Clarke et_ a l . (1963), a characteristic feature of concretionary brown s o i l is a formation of chlorite in the Bcc horizon. It is believed to be related to the moisture regime. Seasonal desication appears to be necessary for the formation of well-ordered chlorite. In eastern Vancouver Island most of the precipitation comes during winters, and summers are usually dry. The s o i l s , therefore, are near saturation during winter, but they are dry in summer to a depth of two feet or more. The seasonal change of the moisture regime in the mild Medi-terranean-like climate would also aid in the liberation and subsequent immobi-lization of the iron as a cementing agent of the concretions. Clarke et a l . (1967) who studied the cation exchange properties of the soils of Vancouver Island found that, in general, the soils had high base saturation even though the precipitation was high. They suggested that the recycling of bases by the dense forest vegetation was a major factor in maintaining the high base status of the soils in this humid coastal area. In addition, they showed that many of the s o i l s , especially in the area with annual t o t a l precipitation over 1000 mm, had large amounts of organic-sesquioxide complexes in the B horizons, although the overall content of exchangeable Ca + Mg are high. This would suggest that, with the long vegetative period on the Island, the annual additions of organic matter were apparently so large that the base supply was not sufficient to bring about the complete decomposition of these complexes, and a residue of organic-sesquioxide complexes have accumulated in the so i l s . The soils in the study area show in general relatively high base saturation and high pH values in spite of the high precipitation. This is probably the result of the parent material which consists mainly of basic 20 volcanic rocks mixed partly with limestone, and also due to the same reason as was discussed by Clarke et_ a l . (ibid.) in the preceding paragraph. In the study area, the base saturation of humus ranges from 10.0$ to 74.3$, surface soils from 3.1$ to 89.4$, subsurface soils from 2,6% to 168.0$ (this extremely high value would be the result of free calcium carbonate in the s o i l s ) j pH value of humus ranges from 3.6 to 6.7» surface soils from 4.1 to 7.4, subsur-face soils from 4.6 to 6.9, cation exchange capacity (in m.eq./lOOg) of the humus ranges from 34 to 173, surface soils from 6 to 58, subsurface soils from 3 to 51; the total amount of exchangeable Ca (eq./cubic metre) in fine textured soils varies from 3.1 to 129.1; the total amount of Mg (eq./cub. m.) varies from 1.0 to 33.8; the to t a l amount of K (eq./cub. m.) ranges from 0.2 to 2.5; the total amount of Na (eq./cub. m.) varies from 0.5 to 4.0; the t o t a l amount of nitrogen (g/cub, m.) ranges from 196 to 2331; and the tot a l amount of available phosphorus (g/cub. m.) ranges from 0.13 to 6.65. Carbon-nitrogen ratios are very variable ranging from 7 to 205. The highest value of the ratio was obtained from an organic s o i l in the form of black muck collected from a "skunk cabbage" site. It i s probably due to the decrease of nitrogen consumed by microbial activity during the extremely slow process of air drying of the s o i l , since the muddy organic s o i l is never dried in nature. In general soils are coarse. Texture of most of the soils were found to be loamy sand, with some soils being sandy loam and sand. Selected samples were analysed with respect to the percentage of extractable iron and aluminum in order to characterize the B horizons for classification pur-poses. Most of the soils in the study area were recognized to be Brunisols 21 (Dystric Brunisols) which covered an extensive area on well drained habitats correlated with the Gaultheria shallon association and the moss association. Only a few of the soils examined were Podzols (Humo-Ferric Podzols) which were found in one case in the moss association, the Achlys - Polystichum asso-ciation and the Vaccinium alaskaense association, respectively. On imper-fectly drained habitats in relation to the Oplopanax - Adiantum association and a part of the Achlys - Polystichum association, soils were found to be mostly Gleysols (Orthic Gleysols). Regosols were found on fresh a l l u v i a l deposits in relation to the Oplopanax - Adiantum association, and on l i t h i c habitats in relation to the Juniperus communis var. montana association. In the Lysichitum americanum association, soils were recognized to be Organic. The prevailing occurrence of Brunisols in the study area in spite of the high amount of precipitation implies the strong influences of parent material over climate. Base-rich parent materials, which consist predominantly of basalt and i t s a l l i e s , supply the high amount of cations which are released through the weathering processes of the parent material, compensating losses through the strong percolation and leaching by rain water. Conse-quently, the development of an eluviated layer and subsequent formation of a podozolic B horizon hardly take place, and the result of this i s an esta-blishment of Brunisols instead of Podzols, even i f the climatic conditions potentially f i t the formation of Podzol as a zonal s o i l in the area. Thus, i t is concluded that the soils in the study area may be called pararendzina soils (Kubiena 1953) developing on base-rich volcanic rocks. 22 6 . Vegetation i . The Coastal Western Hemlock Zone The Coastal Western Hemlock Zone was established by Krajina as one of the eleven Biogeoclimatic Zones in British Columbia (Krajina 1959t>» 1 9 6 5 a , 1969) and has been studied by Krajina (ibid.) and his students: Cordes ( 1 9 6 8 ) , Eis ( 1 9 6 2 a , 1 9 6 2 b ) , Kuramoto ( 1 9 6 5 ) , Lesko ( l 9 6 l ) , Mueller-Dombois ( 1 9 6 5 ) , Orloci ( 1 9 6 1 , 1 9 6 U , 1 9 6 5 ) , Wade ( 1 9 6 5 ) . This zone occurs widely along the coast of the Province. It begins at the immediate coast, reaching eastward up to the mountain-sides of the west slopes of the Coast Mountains and Cascade Mountains, except for areas where annual t o t a l precipitation does not exceed 1600 mm, i.e. most parts of the Fraser Lowland, Sunshine Coast, and souths eastern Vancouver Island, including the Gulf Islands, where the Coastal Douglas-fir Zone becomes established instead. The upper part of the zone is adjoined to the Mountain Hemlock Zone which is promoted by heavy snow accumu-lation, a handicap for the coastal western hemlock zone, Macroclimatically, this zone is characterized mostly by wet Cfb and partly by the mildest Dfb climates, both of which are under strong oceanic influences, summarized (Krajina 1969) as follows: mild and less fluctuating temperatures (mean annual temperature: 5 to 9°C, annual range of temperature: 9 to 21°C, absolute maximum temperature 26 to 40°C, absolute minimum temper-ature -30 to -T°C); high amount of precipitation, most of which occurs during the winter season (annual total precipitaion: 1650 - 6650 mm, seasonal occur-rence of total precipitation in %: rainy season, winter, 30 to k5%\ dry season, summer, 7 to 15%) \ and relatively long frost free period ( 1 2 0 to 275 days). As mentioned in the preceding section, the zonal soils in the coastal western hemlock zone are podzols with thick raw humus accumulation. 23 Under the aforementioned climatic and pedogenic circumstances, on mesic habitats the f i n a l tree species which forms the climatic climax commun-i t i e s is Tsuga heterophylla*. The characteristic combination of species of the zone is as follows: Tsuga heterophylla, Thuja plicata. Menziesia ferruginea, Blechnum spicant. Corallorhiza maculata, Cornus canadensis (sensu lato), Goodyera oblOngifolia. Linnaea borealis. Listera caurina. L. cordata, Hylocomium splendens. Isothecium stoloniferum t Plagiothecium undulatum, Rhytidiadelphus loreus, Bazzania ambigua. B. tricrenata (Krajina 1959b,1965a, Orloci 196l, 1964). Based on primarily the difference of the amount of annual total precipitation and secondarily on the consequential difference in vegetation, the coastal western hemlock zone may be divided into two subzones, the drier subzone (CWHa) and the wetter subzone (CWHb). The drier (or humid) subzone occurs under a relatively dry climate with t o t a l annual precipitation of 1650 to 2800 mm/year. In this subzone, soils may be weakly laterized with concretions. The differential species for the subzone are as follows: Pseudotsuga menziesii. Acer macrophyllum. Cornus n u t t a l l i i , Prunus emarginata. Arbutus menziesii. Sorbus sitchensis, Abies grandis. Pinus monticola, Gaultheria shallon. Mahonia nervosa, Rosa  gymnocarpa. Vaccinium -parvifolium, Eurhynchium oreganum. The climatic' climax community in the subzone is the Plagiothecio (undulati) - Rhytidiadelpho (lorei) - Pseudotsugo - Tsugetum heterophyllae. The wetter subzone develops under a relatively wet climate (perhumid) with annual t o t a l precipitation 2800 mm to 6650 mm, in which soils may be slightly gleyed due to the high amount of precipitation. It is differenti-ated . from the drier subzone by the following species: Abies amabilis, * It is called western hemlock from which the name of the zone is derived. Nomenclature of the Biogeoclimatic zones is based on the characteristic plants of the climatic climax or mesic plant association (Krajina 1959b,1965a). 24 Chamaecyparis nootkatensis. Vaccinium alaskaense. Vaccinium ovalifolium, Rubus pedatus, Clintonia uniflora. Streptopus roseus . Streptopus streptopoides « Rhytidiopsis robusta, Pilopholon h a l l i i . Usnea longissima. The climatic climax community in the subzone is the Rhytidiadelpho (lorei) - Rhytidiopsido (robustae) - Vaccinio (alaskaensis) - Pseudotsugo - Tsugetum heterophyllae. i i . Palynological consideration on the development of vegetation after  the glaciation Similar to other parts of British Columbia, the study area was completely covered by a thick ice sheet during the ice age, except for the high mountain peaks. Therefore, the vegetation is relatively young. The history of the vegetation may be considered to be 10,000 - 12,000 years old. From the palynological studies by Hansen (1947) and Heusser (i960), the post-glacial development of vegetation in North Pacific North America is rela-tively well known. According to Prest (1969), the recession of the last glacier began approximately 12,000 years ago in most parts of the lowland in southern British Columbia. The following is summarized from Heusser (i960): Postglacial time is subdivided into three intervals: l ) a cold, moist climate during the opening interval which started approximately 10,000 years ago and ended about 8,500 years ago; 2) a dry warm hypsithermal interval with maxim-ized temperature, 8,500 years ago to 3,000 years ago; 3) a cool, humid climate which has fluctuated to the present. An analysis of a pollen profile from Menzies Bay, northern Vancouver Island, shows the following history: In the early Postglacial interval in which climate was s t i l l cold and wet, Pinus contorta and Alnus sp. were the prominent representatives of the vegetation, accompanied by Salix spp. and Carex spp. The early Postglacial contains the pioneer stage of plant succes-sion that gave rise to the climax communities. A cold, humid climate 25 sustained Pinus contorta where i t grew, but the maintenance of the tree was made possible by continuing disturbances which prevented climax communities from getting established. Pinus contorta and Alnus rubra are the important members of the vegetation in the i n i t i a l stage of succession. Both of them require open habitats and can occur on regosolic soils and l i t h o s o l i c s o i l s . Alnus rubra especially has a great advantage in being able to compete with other plants on nitrogen-deficient soils due to i t s symbiosis with nitrogen fixers (Uemura 1952, Neal et. a l . 1968, Newton e£ al.1968). During the hypsi-thermal interval in which climate was warm and dry, the noticeable phenomenon was an invasion and establishment by an assemblage of (more or less) shade tolerant conifers principally Tsuga heterophylla and Picea sitchensis, i n -cluding Pseudotsuga menziesii. Pinus monticola. Abies sp. and Tsuga  mertensiana (at higher elevations). Pinus contorta and Alnus sp. remained but comparatively decreased. Lysichitum entered the vegetation at the stage. This would indicate that enough organic matter (in the form of black muck) had been accumulated to sustain the species. Toward the end of the interval, Tsuga heterophylla became dominant, occasionally mixed with Pseudotsuga  menziesii. Perhaps s o i l formation and horizon differentiation could have been f a i r l y advanced with thick accumulation of acid raw humus. In the late Postglacial interval which has continued to the present time, climate returned to cool and wet. During this period, Tsuga heterophylla and Picea  sitchensis were apparently predominant, forcing other species including Pinus contorta and Alnus sp. to low ranks. Peat bog formation is one of the characteristics of this time, which indicates enough development of hard pans to keep the ground water from escaping downward and consequential formation of shallow water basins on which Sphagnum species got established (Wade 1965). 26 It is conceivable that, at this stage, the vegetation was well diversified and some of i t was close to the climax stages. i i i . Vegetation in the study area The whole study area is entirely covered by forests (Figure 3, h and 5), except for extremely unfavorable habitats, e.g. rock outcrops, fresh talus deposits, fresh a l l u v i a l deposits, pathways of avalanches during winter, and aquatic habitats. Most parts of the forests are dominated by Pseudotsuga  menziesii which extends up to 850 - 1,000 m above sea l e v e l , where they are gradually replaced by a forest dominated by Tsuga mertensiana,, which belongs to the Mountain Hemlock Zone. This kind of forest, however, is not included in the present study. Throughout the forests, Pseudotsuga menziesii, Tsuga heterophylla. Thuja plicata and Abies amabilis are the major constituents of the tree layer. Minor constituents include Abies grandis, Chamaecyparis nootkatensis. Pinus  monticola, Acer macrophyllum and Cornus n u t t a l l i i . Of these, Pseudotsuga  menziesii is the predominant tree species which composes the uppermost layer (A^) of the forest canopy. Its growth in the study area is so good that some of the individuals attain a very large size (more than 150 cm in d.b.h. and 70 m in height). Site index shows the best growth of the species in the area to be 57 m/100 years, which is obtained in the Achlys - Polystichum association. Most of the trees are relatively young. From the tree mensu-ration data, their ages were found mostly to be between 200 and 300 years. Pseudotsuga menziesii, however, is not self-regenerating except in very dry habitats. Its seedlings are infrequent in the understory of the forest canopy, presumably due to i t s shade intolerance under the humid climate, even though soils are rich enough for their requirements. Usually Pseudotsuga menziesii 27 Figure 3 . General view of the study area, showing Wolf River Valley. The highest peak i s Golden Hinde ( 2 2 2 8 m). (VIII 8 , 1968) Figure h. General view of the study area, showing Buttle Lake and Mt. McBride. (VIII 2 , 1968) 28 easily gets established after f i r e as a pioneer tree in the secondary suc-cession. Under the humid climate, however, abundant dead trees, as they decay, promote the leaching of soils and consequently provides more favorable habitats for Tsuga heterophylla than for Pseudotsuga menziesii. This would be also a cause which impedes the regeneration of Pseudotsuga menziesii. Tsuga heterophylla. on the other hand, is found commonly in the subdominant layer (A^) and the suppressed layer (A^) under the crowns of Pseudotsuga menziesii. In most cases, the trees of this species are smaller than Pseudotsuga menziesii. but their ages are more or less the same. Tsuga  heterophylla is known to be rather disadvantaged on the mineral rich habi-tats, even though i t is more shade tolerant and more adapted to the humid and perhumid climate than Pseudotsuga menziesii. Nevertheless, i t is conceivable that Pseudotsuga menziesii. though i t is highly dominant at present, w i l l be replaced by Tsuga heterophylla as i t s l i f e span is terminated, provided that enough mor type of humus has been accumulated on the ground surface, which would greatly benefit Tsuga heterophylla for i t s establishment. Thuja piicata is occasionally found in the subdominant layer and/or suppressed layer where i t is mixed with Tsuga heterophylla. Although i t s shade tolerance is as high as that of Tsuga heterophylla. other ecological characters are quite different. It requires habitats rich in mineral nutri-ents as well as water and i t cannot withstand strongly acid s o i l s , whereas Tsuga heterophylla is well adapted to acid and poor habitats in mineral nutri-ents. Thus, permanent seepage habitats, where enough cations as well as water is supplied by the continuous seepage, are preferable for i t . Indeed, in the study area, on a l l u v i a l habitats along small streams i t thrives very well completely dominating in the uppermost layer. Particularly on an a l l u v i a l 29 flood plain in the Wolf River Valley, where the parent material i s partly limestone and the base saturation of the soils i s very high (over 60%), Thuja plicata shows the best growth (maximum size of the tree: 175 cm in d.b.h. , 65 m in height, site index 49 m/100 years) in the study area, being associated with Oplopanax horridus in the shrub layer and with Plagiomnium  insigne in the moss layer. Abies amabilis is a species which requires a perhumid climate (total precipitation more than 2800 mm/year) and rich habitats in nutrients (Krajina 1969). It i s , however, rather d i f f i c u l t for the species to find suitable habitats, because the high amount of precipitation tends to cause rapid removal of the minerals such as calcium, magnesium, sodium and potas-sium, unless enough minerals are continuously supplied from the parent ma-t e r i a l by weathering or biogeochemical cycling to compensate for the loss of them. The study area is one of the cases in which the depauperation of soils hardly takes place in spite of the high precipitation, because of richness of the parent material. As was discussed ear l i e r , soils in the study area are generally rich in basic minerals due to the particular par-ent material which consists predominantly of basalt and i t s a l l i e s and partly limestone. Abies amabilis i s , therefore, favored by the subeutrophic s o i l conditions and high amount of precipitation in the study area. Thus, Abies amabilis successfully gets established, dominating or co-dominating with Tsuga heterophylla in the Elk River Valley, Heber River Valley and the upper Wolf River Valley where annual t o t a l precipitation i s .>.«-' suggested to exceed 2800 mm. In the v i c i n i t y of Buttle Lake, where the climate is the driest in the study area, Acer macrophyllum and Cornus n u t t a l l i i are found commonly. 30 Figure 5 . General view of the Wolf River V a l l e y f o r e s t . Due to extremely r i c h parent m a t e r i a l c o n s i s t -ing of mainly basalt and some limestone, Thu.1a  p l i c a t a i s the dominant accompanied by Pseudotsuga menziesii and 'Tsuga, heterbbhylla. (VIII 8, 1968) Figure 6, A w e l l developed c o r t i c o l o u s community on the bark of Acer macronhvllum. Major constituents include Claonodium b o l a n d e r i . Neckera d o u g l a s i i . II. m e n z i e s i i . Homalothecium fulgescens. H. n u t t a l l i i , Hypnum sub- inrponens. Isothecium stolbniferum, Plagiomriium  venusturn. F r u l l a n i a n i s r i u a l l e r i s i s . P o r e l l a cordaeana. P., n a v i c u l a r i s and Radula bolanderi. ~Myra Creek, VIII 21, 1969] 3 1 Though they are not dominant trees in any situation, their growth is f a i r l y good. Acer macrophyllum reaches a size of up to 55 cm in d.b.h. and 43 m in height, especially when i t grows on small a l l u v i a l fans formed by the lake shore. These trees are occurring mostly in the Achlys - Polystichum association. A well developed corticolous community on the bark of Acer  macrophyllum is a remarkable feature (Figure 6 ) . The community includes such epiphytic species as Dendroalsia abietina, Neckera menziesii, Neckera  douglasii. Claopodium bolanderi. Homalothecium fulgescens. Homalothecium  n u t t a l l i i , Plagiomnium venustum, Porella cordaeana, Porella navicularis*, Hypnum subimponens, Isothecium stoloniferum. Radula bolanderi*, Frullania  nisquallensis*« and Polypodium glycyrrhiza. These plants are mostly neutro-philous species which require a calcium rich and low acid substratum. Szczawinski (1953) named this kind of corticolous community as Isothecium  stoloniferum - Neckera menziesii - sociation. Abies grandis is rather rare in the study area. It may occur occasionally on the east side of Buttle Lake as scattered individuals in the Achlys - Polystichum association and the Oplopanax - Adiantum associ-ation. On a rocky c l i f f on east side of Buttle Lake, there is a small stand of Arbutus menziesii (Figure 7 and 8), which could be one of the most northern limits of the geographical distribution of the species**. The com-munity structure of the stand is shown in Table 2. Several small individ-uals of the species are found scattered on rocky c l i f f s on the west side of Buttle Lake, too. On extremely dry habitats with shallow soils (30 - 50 cm)on bedrock, * These bryophytes grow on the dead material of other mosses. ** Many small trees of Arbutus menziesii occur on rocky habitats of the north shore of Muchalat Inlet, on the west coast of Vancouver Island. 32 Figure 7. Arbutus menziesii. occurring on a rocky c l i f f facing Buttle Lake. The s i t e has the least amount of r a i n f a l l i n the study area. (East side of Buttle Lake, VII 14, 1969) Figure 8 . Arbutus menziesii, occurring on a rocky c l i f f . (East side of Buttle Lake, VII 14, 1969) 33 Table 2 , A community stracture of Arbutus menziesii stand Species species significance species species significance Tree layerj Arbutus menziesii 5 Pseudotsuga menziesii 3 Pinus contorta 4-Shrub layerj Arbutus menziesii 2 Rubus ursinus + Mahonia nervosa 2 Pseudotsuga menziesii + Symphoricarpos mollis 2 Herb layerj Festuca occidentalis 3 Elymus glaucus 2 Prunella vulgaris 3 Polygonum nuttallii 2 Achillea millefolium Mimulus guttatus 1 ssp. lanulosa 2 Hieracium albiflorum 1 Gollinsia parviflora 2 Cryptogramma crispa + Montia parvifolia 2 Moss layer: Rhacomitrium canescens 7 Polytrichum piliferum 1 Stereocaulon tomentosum 6 Dicranum fuscescens 1 Dicranum howellii 5 Peltigera aphthosa 1 Selaginella waliacei 5 Isothecium stoloniferum + Cladonia rangiferina 4 Antltrichia curtipendula + Rhacomitrium heterostichum 2 Parmelia saxatilis •f Polytrichum juniperinum 2 Cladonia gracilis var, elongata + 3k Juniperus communis var. montana is found forming dense patches, some of them quite large. It is frequently associated with Arctostaphylos uva-ursi, Hieracium albiflorum and Fragaria virginiana. The habitats are too dry and soils are too shallow to support any trees. Only a few stunted trees of Pinus contorta and Pseudotsuga menziesii may occur in this community. Some-times- Holodiscus discolor may be found on extremely dry habitats around rock outcrops, accompanied by Elymus glaucus. Festuca occidentalis. Danthonia  spicata, Allium cernuum. Antennaria neglecta. Erlophyllum lanatum, Rhacomitrium canescens. Stereocaulon tomentosum and Cladonia rangiferina. Picea sitchensis is practically missing in the study area except for a small individual growing close to the Strathcona Park Lodge. This is a species which requires extremely rich habitats in mineral nutrients, especially in magnesium. Thus, in the coastal western hemlock zone, i t is found commonly on permanent seepage habitats, associating with Lysichiturn  americanum. It also occurs close to sea shore where ocean spray supplies the habitats enough amount of minerals, accompanied by Maianthemum dilatatum in the lesser vegetation. The importance of the lesser vegetation l i e s in the fact that generally they are more sensitive to environmental variation (Cajander 1909, Krajina 1933, Becking 1957). In other words, the constituents of the lesser vegetation frequently have relatively narrow ecological amplitudes, and, therefore, they are more easily sorted and arranged along the environmental gradient according to their requirements or tolerances to environmental con-ditions. A plant community is an aggregation of species which are not randomly thrown into i t , but are substantially sorted based on their inter-locking ecological characters. Thus, most of the species in the community 35 have more or less similar requirements or tolerance to the particular envi-ronment. At least, there must be "the greatest common factors" which bind the aggregation. Since the phytogeocoenosis is a vegetation-environment complex which f i t s a particular location on the earth, i t would be possible to re-present i t by a species or a combination of species which are well adapted to the particular environment and consequently highly correlated with i t . This is the basic idea of "characteristic species". However, as a matter of fact, the ecological distribution of a species which belong to a certain phytogeocoenosis might overlap with those of other species of different phyto-geocoenoses at the both ends of the distribution, since the environmental gradient is essentially continuous. It i s , however, s t i l l possible to em-ploy these species as the best expression of the phytogeocoenosis at their optimum conditions. This idea has been well developed in the s c i e n t i f i c f i e l d (Cajander 1 9 0 9 , Clements 1 9 2 0 , Chikishev et a l . 1965) as well as prac-t i c a l application (Hilgard i 8 6 0 , Pearson 1 9 1 3 , Sisam 1 9 3 8 , and Silker 1 9 6 3 ) . The constituents of the lesser vegetation, when they strongly represent the phytogeocoenoses, could be employed as the characteristic species or a characteristic combination of species for vegetation c l a s s i f i -cation purposes, since they might reflect more accurately the environmental variation than do the individual species or constituents of the tree layers» 36 III. Vegetation Analysis and Synthesis 1. Methods for vegetation analysis i . Premise In order to carry out the present study, basically the methods II which were founded and developed by the phytosociologists in the Zurich -Montpellier school were followed. The details of these methods have been f u l l y discussed and described by Braun-Blanquet (1921, 1932), Poore (1955a, 1955b, 1955c, 1956), and Becking (1957). The methods which had been modified by Krajina (1933) were also employed here. In total ninety-nine plots were established throughout the study area to represent the phytogeocoenoses. A plot is considered here as a sampling unit from which various kinds of information on the vegetation as well as environment are obtained; further-more, i t is regarded as an "association individuum" (Braun-Blanquet 1932) which is a complete sample of a plant association. i i . Selection of plots In advance to setting up the plots, survey trips were carried out to gather general information of the study area and to find the community types provisionally in the area. The plots were selected subjectively so that the homogeneous stands in both f l o r i s t i c and ecotopic sense were included. The homogeneity of the stands is an essential prerequisite for a phytocoeno-logical study, even though i t is almost impossible to obtain perfect homogen-eity as a matter of fact, and the assesment is more or less subjective and empirical (Poore 1955a). Special care was taken to avoid heterogeneous and/or disturbed sites. Transitions were also excluded. 37 i i i . Plot size Basically a 20m x 40m ( l chain x 2 chains: 1/5 acre) rectangle was used as a plot size, hut sometimes smaller size or modified shapes were adopted according to the extent and kind of vegetation. Generally large plot size gives more information (Orloci 1964), though i t is more d i f f i c u l t to handle. The following considerations were taken when a plot size was determined: l ) the plot size should be larger than the minimal area (Braun-Blanquet 1932), 2) i t should be much larger than the single coverage of the largest i n d i v i -dual in the community, 3) i t should not be larger than the local spatial ex-tent of the community type which is to be investigated. iv. Analytical procedure Vegetation in the plot was analyzed in reference to the following aspects: 1) Listing of species: a l l vascular plants, bryophytes and lichens were identified and l i s t e d . 2) Layering: the vegetation was s t r a t i f i e d into layers according to their l i f e forms and their height. In the forest communities, the following c r i t e r i a were applied in order to distinguish the strata: A (tree) layer: A^: Dominant trees in the uppermost layer of the forest canopy A2: Subdominant trees A^: Suppressed layer, trees over 5m in height B (shrub) layer: B^: Woody plants over 2m but less than 5m B 2: Woody plants less than 2m in height C (herb) layer: A l l herbaceous plants* regardless their height * Some of the woody plants, e.g. Arctostaphylos uva-ursi, Chimaphila umbellata. Linnaea borealis, Loriicera c i l i o s a , are treated here as herbaceous plants. 38 D (moss) layer: D^: Bryophytes and lichens occurring on humus and surface mineral soils D^w: Bryophytes and lichens occurring on decaying wood Dr: Bryophytes and lichens occurring on rocks E (epiphytic) layer: E : Epiphytic bryophytes and lichens occurring in the A layer E B : Epiphytic bryophytes and lichens occurring in the B layer and more than 0.5m from the ground surface E : Epiphytic bryophytes and lichens occur c less than 0.5m from the ground surface 3) Estimation of species: according to the Domin-Krajina scale, a l l species were evaluated in terms of species significance and the sociability. The scales employed are shown in Table 3 and Table k. h) Tree mensuration: a l l trees over 10 cm in d.b.h. or 5m in height were measured for the d.b.h. and height. Their location in the plot were also measured in order to make a distribution map of tree individuals in the plot. Some of the representative trees were bored using an increment borer to determine their ages. In addition, habitat conditions were described as much as possible. One s o i l p i t was dug to collect s o i l samples. Details concerning the environ-mental conditions are discussed in the next chapter. 39 Table 3 , Species significance scale (Domin - Krajina, 1933) Class Description + Solitary, very low dominance (0 - 1%) 1 Seldom, very low dominance (1 - 2%) 2 Very scattered, low dominance (2 - 3%) 3 Scattered, low dominance (3 - 5%) Covering 5 - 10% of the plot 5 Covering 10 - 20% of the plot 6 Covering 20 - 33% of the plot 7 Covering 33 - 50% of the plot 8 Covering 50 - 75% of the plot 9 Covering more than 75% but less than 100% of the plot 10 Covering 100% of the plot Table 4 . Sociability scale (Krajina, 1933) Class Description + Sociability 0 , individual plants 1 Groups,up to 4 x k cm 2 Groups, up to 25 x 25 cm 3 Groups, up to 50 x 50 cm Groups, up to 1/3 - 3A m2 5 2 Groups, up to 1 - 2 m 6 2 Groups, up to 5 m 7 2 Groups, up to 25 - 50 m 8 Groups, up to 100 m 9 Groups, up to 200 - 250 m 10 Groups, at least 500 m2 1+0 2. Methods for vegetation synthesis Vegetation synthesis is a summation and integration of analytical data which were collected from f i e l d and laboratory work. By abstracting this information, plant associations can be established. It is the most impor-tant process for vegetation synthesis. The plots were cautiously examined and grouped into tentative asso-ciations according to their f l o r i s t i c composition. Plots were arranged in a table principally in sequence of elevation. Then, the presence of each species was calculated into five classes according to Braun-Blanquet (1928, 1932) as shown below (Table 5 ) : Table 5 . Presence and Constance (Braun-Blanquet 1928, 1932) Class Percent of the plots V: constantly present 8 l - 100 IV: mostly present 6 l - 80 III: often present 41 - 60 II: seldom present 21 - 40 I: rare 1 - 2 0 Presence is applied to the case where plot sizes are unequal, whereas Constance is used for the case of equal size plots. Average species significance was also calculated from each species in the table. In the synthetic table, species were arranged f i r s t according to layers, then next according to presence classes within each layer. In the Zurich - Montpellier school, f i d e l i t y is one of the most important characters of an association. It is theoretically a degree of faith-1*1 fulness of a species to a particular association, i.e. ecosystem (Poore 1955a). In other words, i t is a measure of an exclusive occurrence of a species to a particular association due to i t s specialized adaptability to a particular habitat. Such species would well represent the habitat, consequently i t would characterize the association. Thus, a species or an assemblage of species which has a high f i d e l i t y to a particular association is called a character-i s t i c species or a characteristic combination of species, and i t is used to define an association. Although the f i d e l i t y concept is quite worthwhile, i f i t is r i g i d l y followed, the association might become a very large unit, since i t is rather d i f f i c u l t to find such exclusive species with high presence within a small unit, especially when flora i s relatively simple and poor in species. This could be partly the reason why the association (sensu Braun-Blanquet) is broader than the biogeocoenosis (sensu Sukachev) in gene-r a l (Krajina 1969). Furthermore, the association, based s t r i c t l y on f i d e l i t y , would be so broad that i t might cover several different ecotopes (Krajina 1933). As a consequence of t h i s , there would be an invalidation of.the prerequisite of the ecotopic homogeneity of the site. In the present study, the idea of the characteristic combination of species (Braun-Blanquet 1932, Krajina 1933, Orloci 196l) was adopted to typify an association instead of a single or small number of characteristic species. A slight modification was done to the original idea so that the characteristic combination consisted of three different categories of species, i.e. l ) constant dominant species: a species which has high constancy (pre-sence class V) and high dominancy (average species significance more than 5.0); 2) constant species: a species which has high constancy (presence class V) but low dominancy (average species significance less than 5.0); and 3) important companion species: a species which does not belong to any of the 42 above, but tends to associate more or less exclusively with a certain asso-ciation and represent i t . 3. Association concept The "plant association" is a basic unit of vegetation, which is der-fined as a plant community of definite f l o r i s t i c composition, presenting a uniform physiognomy and growing under uniform habitat conditions (The Third International Botanical Congress, Flahault and Schroter 1910). This broad definition, however, has been interpreted variously by different phytosocio-logical schools (Becking 1 9 5 7 ) . In the Zurich - Montpellier school, i t is interpreted as follows: the plant association is an abstraction conceived from examination of a number of stands found in the f i e l d , each of which should have the minimum of characters which personify the association under a l l circumstances (Poore 1 9 5 5 ) , and i t is identified by i t s characteristic species composition, including one or more character species or differentiating species (Meijer Drees 1 9 5 1 ) . The concept of abstract association is compared to the "species" in taxonomy and each stand to the individual in the species (Becking 1 9 5 7 ) . Krajina ( i 9 6 0 ) defined the "plant association" more precisely as the association is a definite uniform phytocoenosis that is in dynamic equilibrium with a certain complex of environmental factors; i t s f l o r i s t i c structure l i e s within limits governed not only by the ecotope, but also by the historical factors of the vegetation development. The term "plant association" was differently interpreted by the phytosociologists in the Upsala school led by Du Rietz. They considered the association to be a concrete unit characterized by constant species (later dominant species were employed) of each layer, emphasizing the stratal structure of the community. They did not admit the "association individuum" 43 concept, because association i t s e l f to them was equivalent to the stands in II the sense of the Zurich - Montpellier school. The use of the dominant species to characterize the community produced a great number of community types. To avoid confusion, Du Rietz ( 1 9 3 2 ) replaced his term "association" by "soci-ation"* which was characterized by a combination of dominant species in each layer, and at the same time he proposed his own vegetation classification system. The "association" which was used by the Clementsian school in North America is completely different. It is more a zonal concept than a phytocoenological one. In relation to climax concept, Clements (Weaver & Clements 1938) considered the "formation" as a basic unit for vegetation classification, regarding i t as a product of macroclimate. To him, the "asso-ciation" was a macroclimatic subdivision of the formation, which was marked by one or more dominants peculiar to i t . Consequently his association covers a very wide geographical range and i t is somewhat analogous to the biogeoclimatic zone (sensu Krajina 1959b, 1965a, 1 9 6 9 ). Poore ( 1 9 5 5 b , 1956) proposed the term "nodum", defining i t as an abstract unit applicable to any category, which is extracted from the repeatedly occuring and relatively easily recognizable plant communities. Cum grano s a l i s . i t is comparable to the "taxon" in taxonomy. 4. Higher and lower units for vegetation classification According to the vegetation classification system used by the ti Zurich - Montpellier school, the associations are grouped into higher unit * "Sociation" was differently used by Szczawinski ( 1 9 5 3 ) to designate c o r t i -colous and lignicolous communities in an association (sensu Braun-Blanquet). called "alliance", by the same concept and manner as is used for the grouping of stands into association. The characteristic species for the alliance are supposed to have wider ecological amplitudes than those at the association level. In the same way, alliances are lumped together into higher units, "orders", amd orders into "classes". On the other hand, an association may be divided into subunits termed "subassociations" or "variants", based on the differential species, which indicate small variations in the environment. characterizing suffixes added to the root of generic names of the character-i s t i c plants as follows: These classification units are hierarchically arranged with the Class: ete a Order: -etalia Alliance: -ion Association: -etum Subassociation: -etosum Variant: -osum 45 IV. Environmental Analysis L Climate In order to obtain general information of the climate in the study area, three weather stations and ten rain gauges were established (Figure 10). They were maintained during the summer seasons of 1968 and I969. The weather staions were allocated approximately on a west-east transect along the Elk River from the western border of Strathcona Provincial Park to the east side of Upper Campbell Lake so that they would show the possible differences of climatic conditions from west to east. As is shown in Figure 2, there was a general trend of climatic change from west to east over the moun-tains. Figure 9. The weather station I, showing a rain gauge and a Stevenson screen containing a Fuess hygrothermograph. (Drum Lakes area, VII 21, 1969) \ Weather s t a t i o n Rain gauge Rain gauge No. R a i n f a l l i n I968 (June 28 - Sept. 3) R a i n f a l l i n I969 (June 5 - Sept. k) Park boundary 0 20 km Figure 10. Location of weather stations and r a i n gauges with r a i n f a l l recorded during summers. 49 Each station include! a Stevenson screen which contained a Fuess hygrothermograph and a maximum and minimum thermometer. The Stevenson screen was settled in an open and f l a t place at a height of 1.5 ni above the ground surface so that the surface temperature would not affect the measure-ments. It was regularly checked and the charts for the hygrothermograph were changed once a week on every Monday morning. Ten rain gauges were dis-tributed covering mostly the northern part of the study area. The instrument used was "Tru-Check Rain Gauge, TRU 202" manufactured by Edwards Manufacturing Company. They were also set up in open, f l a t places to avoid the interception of rain water by tree crowns and other obstacles as much as possible. They were frequently checked and the r a i n f a l l was recorded immediately after the rain stopped. The measurements in three weather, stations were summarized and shown in Figure 11 and 12, There is no considerable climatic difference rec-ognized among them as far as temperature and humidity are concerned. This is probably because the distances between the stations in both vertical and horizontal directions are too small to y i e l d any significant differences. However, an interesting phenomenon was recognized as to the daily cyclic patterns of temperature among the stations (Figure 13). In Station I, the daily maximum temperature always occurred between 1 P.M. and 3 P.M. (Pacific Standard Time), whereas in Station I I I , which was located close to the lake shore of Upper Campbell Lake, i t was delayed to the late afternoon, between 3 P.M. to 5 P.M. (Pacific Standard Time). In Station I I , the situation was somewhat intermediate. The same tendency was observed concerning the daily minimum temperature. This difference in the daily cyclic patterns of temperature at Station III would be the result of the influence of the lake Figure 13. Daily c y c l i c pattern of temperature 51 which acted as a "buffer" to the rapid change of the atomospheric temperature. In Station I I , wind would be a controlling agent, namely, the wind from the lake side would cause the delay of the time of the daily maximum temperature, and vice versa. Concerning r a i n f a l l , as was expected, the western part of the study area, where rain gauge No. 1 and No. 2 were located, received the highest amount of r a i n f a l l during both summers (Figure 5). On the other hand, the least r a i n f a l l tended to be found in the east side of Buttle Lake, where rain gauges No.9 and No. 10 were installed. This climatic trend is reflected in the vegetation of the respective areas, i.e. in the Elk River Valley and Drum Lakes area where the r a i n f a l l was found the highest, Abies amabilis is one of the dominant trees associated with Vaccinium alaskaense. Rubus pedatus t Clintonia uniflora. Streptopus roseus and Plagiothecium undulatum. The Rhytidiadelpho (lorei) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae develops in this area. While, on the east side of Buttle Lake where r a i n f a l l is the lowest in the study area, Arbutus menziesii is found in a small stand, and Abies  grandis. Cornus n u t t a l l i i and Acer macrophyllum are relatively common. Dendroalsia abietina and Plagiomnium venustum are also confined to this area in the study area. 2. Light intensity Needless to say, the essential importance of light for an ecosystem lies in the fact that i t is only_the energy source, both directly and in d i -rectly, to sustain l i f e in the ecosystem. It controls not only the rate of photosynthesis and assimilation of material but also influences plant l i f e in 52 various ways. It is an important factor which controls phenology of plants. Actually the duration of light affects the accumulation of flower promoting hormones in plant tissue and consequential photoperiodism (Went 1948, 1957) which is an essential adaptative character of plants, particularly in high latitudinal regions. Light promotes or inhibits the germination of seeds of some plants (Crocker 1936, Allen 1941, Evenari 1956, Richardson 1959, Ramdeo 1970, Goldthwaite et a l . 1971). It is also known that light does modify the morphological and physiological characters of plants and causes subsequent change of growth forms; even l i f e forms (Niestaedt and Olson 196l, Murray and Nichols 1966, Rackham 1966). If such modifications are genotypi-cally fixed, there would be a differentiation of ecological races or eco-types (Turesson 1922) which are well adapted to particular light conditions, as i t is seen in the cases of Solidago (Bjorkman and Holmgen 1963) and Impatiens parviflora (Evans and Hughes 196l). Synecologically the problem of shade tolerance and intolerance is very significant. A l l plants growing in forest communities must experience shaded conditions for a considerable period of time, since they start from seedlings germinated on the forest floors. Therefore, the amount of light which reaches the forest floor could well be a limiting factor for them, and only the plants which can withstand the shaded conditions self-perpetuate in the sites. Thus, the most shade tolerant species would be potentially f i n a l species in the sites forming climax communities. The concept of shade toler-ance has been practiced since the begining of this century, especially in the f i e l d of forestry. Zederbauer (1908) discussed the relationships between light intensity and tree species in terms of shade tolerance. In eastern North America, the ranking of the forest tree species in respect to their shade tolerance has been well studied by Zon and Grave (1911), Graham (1954) 53 and Bakuzis (1959)t Krajina (l965a,1969) has emphasized the synecological importance of shade tolerance and elucidated the general responses of the forest tree species in British Columbia in respect to tolerance and intolerance. Shade tolerance or intolerance is not a simple phenomenon. It is a total result of a complex interactions of environmental conditions and the internal physiological adjustment of the plants. It is highly influenced by temperature, humidity, nutritional situation and moisture condition. A species which is shade tolerant on xeric habitats becomes shade intolerant on mesic and hygric habitats (Krajina 1965a). The same species which is shade tolerant on habitats poor in mineral nutrient becomes shade intolerant on habitats rich in mineral nutrient (Murray and Nichols 1966). Grime (1966) suggested that the causes of col-lapse of seedling of shade intolerant species under low light intensity were as follows: l) etiolation, 2) high rates of respiration, 3) marked rise of respiration with increase in temperature, and k) less resistance against fungal attack as a result of the aforementioned causes. Actually failure of seedlings in shade is almost invariably associated with fungal attack (Vaartaja 1952, 1953). The great d i f f i c u l t y which is encountered in the f i e l d to deal with the light factor is a strong v a r i a b i l i t y of light conditons both quantitatively and qualitatively (Daubenmire 19^7, Anderson 196Ua, 196Ub, 1966, Evans 1966). Indeed, light conditions are highly dependent upon the latitude, altitude, season of the year, time of day, weather condition, topography, and kinds of vegetation. Vezina and Pech (1964) studied the light intensity in the Abies balsamea forest in Quebec and found the average relative light intensity 54 under the forest canopy to be 5,9% of f u l l sun light. The relationship between the relative light intensity and crown closure was found to be curvelinear which followed the equation y = 100.17(9.623) , where y is the relative light intensity under the canopy and x is percentage of crown closure. The minimum possible light intensity was 2% when the crown closure was 100$. Odani (1963) proposed an equation to calculate the relative light intensity under the forest canopy, which is 1/1^100 =-8 log-^Q I Q + RQ where I is light intensity under the canopy, I is the f u l l light intensity, o and R Q is the constant to a given canopy, and he proposed the value of RQ as an index of light condition inside the forest community. Schomaker (1968) recognized the rate of interception of light by the forest canopy to be 93$ in coniferous forests (consisting of Picea rubens. Tsuga canadensis and Pinus strobus). 83$ in deciduous forests (consisting of Betula populifolia and Fagus grandifolia) in the foliated season and kl% in the defoliated sea-son. Kawano et a l , (1968) also showed the relative light intensity under the forest canopy to be 2 - 12% in Tsuga div e r s i f o l i a forests, 5 - 20% in deciduous forest in the foliated season and 60 - 95% in the defoliated season. The amount of light which reaches the forest floor through the canopy is considered as a factorial product of transmissibility of each leaf and the total mass of leaves in a unit area. The transmissibility of a leaf is known to be 5 - 10% in herbaceous plants and deciduous trees, 2 - Q% in ever-green trees, and the value is inversely correlated with the content of chlorophyll in the leaf (Kasanaga and Monsi 1954). Czarnowski (1959) pro-posed an equation to calculate the mass of leaves for each tree, which is m = k(d+A)^, where m is the mass of leaves, k i s a constant for definite species, l o c a l i t y and biocoenological conditions, d i s d.b.h., and A is a 55 constant for each species, Kira and Shinozaki (i960) used the equation: WI = 9.64D^*^^, where WI is the mass of leaves for the tree, and D is d.b.h., this equation was commonly applicable to three coniferous species (Abies  sachalinensis. Picea glehnii and Picea .jezoensis). In this study, light intensity refers to the light intensity at the height of 1 m above the ground, and i t i s an approximation to that which most of the shrubby and herbaceous plants would receive. The measurements were done using a SekoniCBrockway Exposure Meter, on clear days (cloud less than 20% of the whole sky), between 11 A.M. and 1 P.M. Pacific Standard Time, in June and July. Ten points were selected in each plot in such a manner that the points included four corners and midpoints of four sides of the plot, the centre of the plot and one point being arbitrarily chosen. On each point, the exposure meter was held so that the surface of the photoelectric c e l l , which was covered with a white disk, was horizontally set at a height of 1 m. Then the needle of the exposure meter was read making certain that sun flecks were avoided. When the light was too high either slide 1 or 2 was attached to reduce the incident light. In this case, the reading was corrected with the correction factor, The reading which were originally expressed in foot candles were converted into lux. 3. Rock identification The environmental uniqueness of the study area l i e s in the fact that base rich parent material strongly influences the development of soils as well as concomitant vegetation over the controls of macroclimate, as was discussed in earlier chapters. Therefore, i t was necessary to identify 56 the kinds of rocks which are comprised in the parent material. The parent material consists predominantly of glacial t i l l s and outwash and partly a l l u v i a l deposits. Only a few cases were bedrocks found in the Gaultheria  shallon association and the Juniperus communis var. montana association. Several pebbles were collected from mainly C horizons and occasion-ally B horizons in each plot, and they were identified by Mr. A.W. Lecheminant, in the Department of Geology, University of British Columbia. Following is the summary from a report which was presented by Mr. Lecheminant (l9Tl). The area sampled is underlain primarily by basalts of the Vancouver Group and this dominance i s clearly reflected in the samples examined. Basic volcanic rocks - either massive, amygdaloidal, or brecciated are the most common rock type. Chlorite and quartz are common amygdalae f i l l i n g minerals. Phenocrysts, where present, are usually plagioclase. Pebbles with heavy quartz veining are common, reflecting their greater s t a b i l i t y in the weather-ing environment. In a few cases only an open quartz boxwork remains. Sicker Group rocks can be recognized in a few locations. Chert is the most common, but banded t u f f , greywacke, and limestone have been noted. The presence of these rock types can be related directly to mapped changes in bedrock geology (map 2 - 1965 Geology Comox Lake Area by J. Muller). A few samples of Coast Range granodiorite or quartz monzonite were recognized. These samples were collected within or immediately adjacent to mapped intru-sives. The identified rocks from the individual plot s o i l pits are tabu-lated in Appendix II, 57 k. S o i l analysis In each plot, one s o i l p i t was dug to observe the profile and to collect s o i l samples. The location of the pit was selected so that i t would be typical and representative of the site vegetationally as well as ecotopically. The s o i l profile was described in general character, thickness of horizon, stoniness, root distribution, and presence of water table in the p i t . Usually four s o i l samples which represented the horizons were collected and they were immediately air-dried at the Campsite. In total 377 samples were collected from various horizons for physical and chemical analyses in the laboratory. In the laboratory, the air-dried samples were sieved through the 2 mm mesh sieve, and separated into coarse material and fine earth (2 mm). The following physical and chemical analyses were done on the fine earth samples, as well as an estimate of f i e l d moisture on 270 samples which were not sieved. i Texture; Texture was determined by the hydrometer method (Bouyoucos 1936, 1951). The s o i l suspension was shaken for twelve hours on a reciprocal shaker; the reading were taken after 40 seconds for s i l t and clay, and after two hours for clay. Particle size limits were according to the U.S.D.A. classification (sand, 2.00 - 0.05 mm; s i l t , 0.05 - 0,002 mm; clay, less than 0.002 mm). i i . F ield moisture: Two inch' s o i l cores were collected from each s o i l horizon of a l l s o i l profiles. The cores were contained in specially designed cardboard containers, sealed with masking tape, then weighed in the f i e l d . Later in the laboratory, they were dried in an oven at 105°C for.twenty-four hours, then re-weighed. Thus the loss of the weight was considered as the amount of water contained within the cores. Bulk density was calculated 58 from these samples and f i e l d moisture was expressed on a volume basis. i i i . Field capacity: Field capacity is the percentage of water in a s o i l after drainage has ceased and after the capillary adjustments have taken place. It is closely estimated by the percentage of water at 1/3 bar tension in a fine s o i l (Peters 1 9 6 5 ) . Soils saturated by water (immersed in water for twenty-four hours) were placed on a pressure plate and were kept for forty-eight hours under a tension of 1/3 bar. Following this process, they were weighed and the water content was calculated. iv. Hydrogen-ion activity (pH): Soils were mixed with d i s t i l l e d water in the ratio of 1 :5 soil:water. They were well stirred by a Vari Speed Stirrer for one minute then l e f t for twenty-four hours, with frequent shaking. Readings were taken electrometrically using the Radiometer pH meter Model 2 5 . v. Exchangeable cations (calcium, magnesium, sodium, and potassium)-" Ten grams of air-dried s o i l (5 grams in the case of organic soils) was extracted with 100 cc. of 1 N ammonium acetate (pH adjusted to 7 . 0 ) . They were stirred well by a Vari Speed S t i r r e r , then l e f t for twenty-four hours, with frequent shaking, and then f i l t e r e d gravimetrically. Cation concentrations were determined by a Digital Concentration Readout of Perkin-Elmer Atomic Absorption Spectrophotometer Model 303. Readout was corrected with dilution factors and expressed in milli-equivalents per hundred grams of s o i l (me/100 g.). v i . Other chemical properties: The determination of total nitrogen, total carbon, available phosphorus, cation exchange capacity and determination of percentage of iron and aluminum for selected samples was done in the laboratory of the Department of S o i l Science, University of British Columbia. The result of physical analysis of soils is given in Appendix III, chemical analysis in Appendix IV, and iron and aluminum determination in Appendix VI. 59 V. Description of Phytogeocoenoses The term phytogeocoenoses, as used by Krajina and his students, is a vegetational part of a biogeocoenosis (sensu Sukachev), which is a mani-festation of a particular ecotope. It can be abstracted and described in terms of plant association (sensu Braun-Blanquet) which is comparable with a type of biogeocoenoses (sensu Sukachev). In the present study, phytogeocoenoses are described based on the association as the basic unit of phytogeocoenoses. Associations are fur-ther categorized according to the synsystematic hierarchy which has been II established and developed by phytocoenologists in the Zurich - Montpellier school. In the present study, phytogeocoenoses are rather unique due to the strong influences of base-rich substrata. Some d i f f i c u l t y was, therefore, encountered in delimitation and classification of the phytogeocoenoses, especially at the higher level of integration. Four orders, eight alliances and eight associations with five variants were established in this study. A general synopsis of the hierarchy is shown in Table 6, and the characteristic combinations of species for the orders and alliances are given in Table 7. Details of the associations i n -cluding the variants are presented succeedingly. Besides these, communities of Populetalia balsamiferae Krajina 1969 could be found on a l l u v i a l habitats, although they are absent in the study area as a matter of fact. This is probably because suitable habitats have been submerged, since the Strathcona dam was constructed. In this text, for the sake of convenience in practice, the Anglicized Table 6. A general synopsis of ORDER ALLIANCE PSSUD0TSUG3TALIA KENZIESII Krajina 1969 •Festuco (occidentalis) - Junlperlon communis montanae Kojlma 4 Krajina Gaultherlon shallonis Kojlma & Krajina TSUGETALIA HETEROPHYLLAE Krajina 1969 Hylocomio (splendentis) - Pseudotsugo -Tsugion heterophyllae Kojlma 4 Krajina Vaccinio (alaskaensis) - Abieto (amabilis) Tsugion heterophyllae Kojlma 4 Krajina THUJETALIA PLICATAE Krajina. in Brooke 1965 Krajina 1969. Brooke et a l . 1970 Mahonio (nervosae) - Polystichion muniti Kojlma & Krajina Oplopanaclon horridl Krajina In Brooke I965, Brooke et a l . 1970 Lysichition amerlcani Krajina in Brooke 1965, Brooke et a l . 1970 SFIRASO - MYRICETALIA • CALIS Kojlma 4 Krajina Spiraeo (douglasii) - Myrleion galls Kojlma 4 Krajina hierarchy ASSOCIATION Hylocomio (splendentis) - Festuco (occidentalis) - Juniperetum communis montanae = the Junlperus communis var. montana association Hylocomio (splendentis) - Eurhynchio (oregani) - Gaultherio (shallonis) - Pseudotsugetum menziesii = the Gaultherla shallon association Hylocomio (splendentis) - Eurhynchio (oregani) - Kahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae =• the moss association Rhytidiadelpho (lorei) - Plagiothecio (undulati) - Rubo (pedati) -Vaccinio (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae a the Vaccinium alaskaense association Eurhynchio (oregani) - Tiarello (trifoliatae) - Polysticho (muniti) -Achlydo (triphyllae) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae = the Achlys - Polystichum association Plagiomnio (insignis) - Leucolepido (menziesii) - Adianto (pedati) -Oplopanaeo (horridl) - Thujetum plicatae " the Oplopanax - Adiantum association Sphagno (girgensohnii) - Rhizomnio (perssonli) - Lysichitetum americani = the Lyslchltum amerlcanum association Campylio (polygami) - Carlco (sitchensis) - Spiraeo (douglasii) -Kyricetum galls » the Myrlca gale association ON O T a b l e 7. C H A R A C T E R I S T I C C O M B I N A T I O N S O F S P E C I E S F O R T H E O R D E R S A N D ( V a l u e s g i v e n a r e t h e a v e r a g e s p e c i e s s i g n i f i c a n c e and p r e s e n c e c l a s s ) A L L I A N C E S ORDER PSEUOOTSUGETALIA ALLIANCE F - J G ASSOCIATION J * G * N u f l b e r o f p l o t s P S E U D 0 T S U G E T A L I A M E N Z I E S I I T S U G E T A L I A H E T E R O P H Y L L A E Tsuga h o t e r o p h y l 1 a T a x u s b r e v i f o i 1 a A m e l a n c h l o r a l n i f o l l a C o r n u s c a n a d e n s i s G o o d y e r a o b l o n g ! f o l i a P y r o l a s e c u n d a L i s t e r a c o r d a t a L i s t e n c a u r l n a D r y o p t e r i s austri3ca R h y t i d i a d e l p h u s l o r e u s R h y t i d i o p s i s r o b u s t a ( V a c c i n i u m p a r v i f o l i u m ) ( L l n n a e a b o r e a l 1 s ) H y l o c o m i o - P s e u d o t s u g o - T s u g i o n h e t e r o p h y l l a e H y l o c o m i u n s p l e n d e n s M a h o n i a n e r v o s a E u r h y n c h i u m oreganura V i o l a s e m p e r v i r e n s C h i m a p h l l a m e n z i e s i i P y r o l a p i c t a C o r a l l o r b t z a raacvlata H y p o p i t y s m o n o t r o p a Homitomes c o n g e s t a V a c c i n i o - A b i e t o - T s u g i o n h e t e r o p h y l l a e V a c c i n i u m a l a s k a e n s e A b i e s a m a b i l i s P l a g i o l h e c t u m u n d u l a t u m C l i n t o n i a u n l f l o r a Rubus p e d a t u s S t r e p t o p u s r o s e u s M e n z i o s i a f e r r u g i n e a S t r e p t o p u s s t r e p t o p o i d e s S o r b u s s i t c h e n s i s 81echnum s p i c a n t T H U J E T A L I A P L I C A T A E T h u j a p l i c a t a A c e r m a c r o p h y l l u m C o r n u s n u t t a l l i i Rubus s p e c t a b i l i s S y n p h o r f c a r p u s a l b u s R i b c s d i v a r l c a t u m A c h l y s t r l p h y l l a P o l y s t i c h u m muniturn T i a r e l l a t r l f o i l a t a O i s p o r u r a h o o k e r ! S m i l a c i n a s t e l l a t a A d e n o ' c a u l o n b l c o l o r • S t r e p t o p u s a m p l e x i f o l l u s ii/niiiiu::ii'i»i nm <x•yuinur'tii A c e r g l a b r u n j M o n t i a s I b i r i c a A s a r u m c a u d a t u m L u z u l a p a r v i f l o r a A c t a e a r u b r a M a h o n i o - P o l y s t l c h i o n m u n i t i 2 . 0 / 1 1 3 .W A c h l y s t r i p h y l l a P o l y s t i c h u m muni t u n L a c t u c a m u r a l i s T r i e n t a l i s l a t i f o l i a T i a r e l l a l a c l n i a t a F e s t u c a s u b u l i f l o r a ( E u r h y n c h i u m o r e g a n u m ) ( H y l o c o m i u m s p l e n d e n s ) ( M a h o n i a n e r v o s a ) ( R u b u s u r s i n u s ) ( R u b u s p a r v i f l o r u s ) Q p l o p a n a c i o n h o r r i d l O p l o p a n a x h o r r i d u s A d i a n t u m p e d a t u m L e u c o l e p i s m e n z i e s i i A t h y r i um f H i x - f e m i n a G a l i u m t r l f l o r u m E u r h y n c h i u m p r a c l o n g u m v a r . s t o k e s i i V i o l a g l a b e l l a L y s i c h i t i o n a m e r i c a n l L y s t c h i t u r n a m e r i c a n u m Sphagnum g l r g e n s o h n i i R h i z o m n i u m p e r s s o n i i ' P e l 11 a n c c s i a n a C o p t i s a s p l e n i f o l i a R h i z o m n i u m nudum S P I R A E O - M Y R I C E T A L I A G A L t S 3 . 4 / V 0 . 8 / 1 1 P s e u d o t s u g a m o n z i o s i 1 6 . 0 / V H o l o d i s c u s d i s c o l o r 0 . 8 / 1 A m o l a n c h i o r a l n l f o l i a 0 . 2 / 1 1 f o s l u c a o c c i d e n t a l i s 0 . 2 / 1 V Wl Hylocomium splendens 3 . A / V 7 . 0 / V T r a c b y b r y u m m e g a p t l l u m 0 . 8 / 1 1 0 . 3 / 1 1 R h y t i d i a d e l p h u s t r i q u e t r u s 0 . 6 / 1 1 0 . 5 / 1 1 F e s t u c o - J u n l p e r i o n coMunis montanae J u n i p e r u s communis v a r . montana 8 . 6 / V A r c t o s t a p h y l o s u v a - u r s l 3 . 2 / 1 I I . F r a g a r i a v i r g i n i a n a 2 . 2 / 1 I I P l e u r o i i u m s c h r e b e r l 1 . 6 / 1 I I 0 . 5 / 1 1 L o m a t i u n m a r t i n d a l e i 0 . 8 / 1 I I H i e r a c i u m a l b l f l o r u r a . / I I I G a u l t h e r t o n s h a l l o n t s G a u l t h e r i a s h a l l o n + /I 7 . 9 / V V a c c i n i u m p a r v i f o l i u m 4 . 1 A L i n n a e a b o r e a l i s 3 . 3 / V M a h o n i a n e r v o s a 2 . 7 / V E u r h y n c h i u m oreganum 2 . 7 / V C h i m a p h l l a umbel l a t a 1 . 8 / V Rubus u r s i n u s 0 . 8 / 1 1 Wll ( R h y t i d i a d e l p h u s l o r e u s ) 2 . 4 / V ( G o o d y e r a o b l o n g i f o l i a ) wv ( P y r o l a p i c t a ) • * / I I I 4 . 5 / V Wl 0 . 2 / I I 0 . 1 / 1 Wv Wl Wl Wl 2 . 4 / V 1 . 7 / V 4 . 1 / V 3 . 3 / V 7 . 0 / V 2 . 7 / V 2 . 7 / V 0 . 1 / 1 1 f + / I I I + / I I I • / I 0 . 1 / 1 Wl Wl Wl 2 . 5 / V + / I I I 0.1/111 2 . 7 / V 7 . 0 / V 2 . 7 / V WH TSUGETALIA H - P - T V - A . T » o * V 6 . 3 / V 0 . 1 / 1 1 5 . 6 / V 0 . 3 / 1 1 1 0 . 5 / 1 1 1 1 .4/111 1 . 3 / I V 3 . 3 / V 2 . 7 / V 4 . 3 / V 3 . 9 / V 1 . 5 / I V • / I I I 3 . 3 / V 0 . 1 A + / I I I 0 . 1 / 1 1 . 2 / 1 V 1 . 8 / I V 0 . 1 / 1 1 0 . 1 / 1 1 1 6 . 9 A + / I I I 5 . 6 / V 5 . 7 / V 5 . 4 / V 4 . 4 / I V 3 . 6 / V 0 . 6 / 1 1 0 . 6 / 1 I I 0 . 1 / 1 1 Wll 0 . 2 / 1 1 . 3 / I V 3 . 8 / V 0 . 6 / I I I 0 . 7 / I V 1 . 0 / I V 0 . 1 / V Win WIV Wll 0 . 1 / 1 I I 0 . 1 / 1 I I 0 .1/11 Wl WH Wl Wl Wiv Wl Wl Wl , Wl 0 . 4 / 1 I I 0 . 1 / 1 I I Wl 3 . 3 / V 6 . 9 A 1 . 6 / I V 1 . 4 / 1 1 2 . 7 / 1 V 0 . 2 / V 0 . 4 / 1 1 0 . 2 / 1 3 . 3 / V 1 . 2 / I V 2 . 2 / V 1 . 7 / I V 2 . 7 / V 1 . 8 / I V 1 . 0 / I V 0 . 1 / 1 I I 1 . 4 / I H 0 . 1 / 1 1 0 . 1 / 1 1 . + / I V 1 . 3 / 1 1 1 0 . 1 / 1 0 . 2 / 1 1 1 0 . 1 / 1 0 . 5 / 1 1 Wl 0 . 1 / 1 6 . 1 A WH 2 . 5 / V 2 . 2 / V 1 . 0 / I V 1 . 7 / V 4 . 2 / V 0 . 1 / 1 1 0 . 1 / 1 1 1 . 6 / I V + / I V Wll 2 . 5 / V 1 . 7 / V 4 . 2 / V 0 . 5 / I V 0 . 1 / 1 1 ! Wll Wl Wl 1 . 8 / I V 1 . 6 / I I I 0 . 5 / 1 1 3 . 2 / I V 4 . 0 / 1 V 0 . 2 / 1 0 . 8 / I I 1 . 2 / 1 1 0 . 6 / I I 0 . 8 / 1 1 0 . 3 / I I 0 . 1 / 1 Wl 0 . 5 / 1 1 0 . 1 / 1 1 0 . 6 / 1 1 1 . 3 / I V Wl 0 . 1 / 1 Wl Wl Wl Wl 0 . 3 / 1 2 . 5 / V 3 . 2 / V 1 . 2 / I V 6 . 0 / V 4 . 0 / V . + / I I I 0 . 9 / 1 V Wl 3 . 8 A 2 . 4 / I V 0 . 2 / I 0 . 7 / I V 0 . 2 / 1 1 1 2 . 4 / V 1 . 4 A 0 . 3 / I I 0 . 2 / 1 1 Wl 0 . 8 / I V 1 . 5 / I V 0 . 2 / 1 I I Wl . 1 . 0 / 1 II 1 . 3 / J I I Wl 0 . 1 / 1 1 Wl 0 . 3 / 1 1 1 1 . 1 / I V 0 . 2 / 1 I I 1 . 0 / I V 1.3/V _ • . - / J - _ 0 . 1 / 1 • / I I I 2 . 3 / I V t Wl o!i/i •Wl # • Wl -t / r .Wl. I.' "• \ + /I Wi Wl Wl Wl Wl • 3 . 2 / V 0 . 9 / I V WH 0 . 1 / 1 Wll 3 . 9 / V 5 . 6 / V 4 . 3 / V + / I I I 1 . 2 / I V Wl Wl 1 .4/111 0 . 1 / 1 1 0 . 1 / 1 Wl 0 . 3 / 1 1 2 . 2 / 1 1 1 0 . 2 / 1 0 . 8 / 1 1 0 . 5 / 1 1 0 . 2 / 1 1 . 7 / I V 0 . 1 / I I I 0 . 6 / 1 1 1 1 . 5 / 1 1 1 • /I 1 . 4 / 1 1 WH 0 . 8 / 1 1 0 . 6 / 1 1 1 1 . 5 / 1 1 1 0 . 1 / 1 1 Wl 4 . 0 / V 2 . 4 / I V + / I I I 0 . 2 / 1 1 W l WH 1 . 5 / 1 1 1 0.8/1.1 0 . 6 / 1 1 1 0 . 8 / 1 1 1 61 THUJETALIA M - P 0 L A . P * 0 - A ' L * SPIRAEO . MYRICETALIA S - M My" 0 . 1 / 1 1 0 . 6 / 1 I I 6 . 7 / V Wi 0 . 3 / 1 1 1 5 . 1 / V 0 . 4 / 1 1 3 . 1 / V 0 . 3 / 1 0 . 7 / I V 2 . 5 / V Wl 0 . 2 / I V 0 . 5 A 2 . 1 / I V • 0 . 2 / 1 1 0 . 2 / I V 0 . 8 / I I 1 . 5 / 1 1 1 5 . 8 / V 0 . 2 / I 1 2 . 2 / I I I 1 . 0 / 1 1 0 . 2 / 1 0 . 2 / I I + / I V 0 . 2 / 1 1 0 . 1 / 1 0 . 7 / I V . 0 . 3 / I V Wl , 0 . 2 / 1 1 Wl 1 . 3 / I V Wi + / I I I Wl Wl 0 . 6 / 1 1 1 . 3 / 1 1 3 . 6 / I V S p i r a e o - My r i c l on g a l 1 s M y r i c a g a l e C a r e x s i t c h e n s i s S p i r a e a d o u g l a s i i V i o l a p a l u s t r i s Campy1i um polygamum F i s s i d e n s a d i a n t h o l d e s H y p e r i c u m formosum G a l i u m t r i f i d u m 1 . 0 / I V # ) J . G: Ho V A - P 0 - A L My H y l o c o m i o ( s p l e n d e n t i s ) - F e s t u c o ( o c c i d e n t a l i s ) - J u n i p e r e t u m communis montanae ' H y l o c o r a i o ( s p l e n d e n t i s ) - E u r h y n c h i o ( o r e g a n i ) - G a u l t h e r i o ( s h a l l o n i s ) - P s e u d o t s u g e t u m m e n z i e s i i H y l o c o m i o ( s p l e n d e n t i s ) - E u r h y n c h i o ( o r e g a n i ) - M a h o n i o ( n e r v o s a e ) - P s e u d o t s u g o - T s u g e t u m h e t e r o p h y l l a e R h y t i d i a d e l p h o ( l o r e i ) - P l a g i o t h e c i o ( u n d u l a t i ) - Rubo ( p e d a t i ) - V a c c i n i o ( a l a s k a e n s i s ) - A b i e t o ( a m a b i l i s ) - T s u g e t u m h e t e r o p h y l l a e E u r h y n c h i o ( o r e g a n i ) - T i a r e l l o ( t r i f o l i a t a e ) - P o l y s t i c h o ( m u n i t i ) - A c h l y d o ( t r i p h y l l a e ) - P s e u d o t s u g o - T s u g o ( h e t e r o p h y l l a e ) - T h u j e t u m p l i c a t a e P l a g i o m n i o ( i n s i g n i s ) - L e u c o l e p i d o ( m e n z i e s i i ) - A d i a n t o ( p e d a t i ) - O p l o p a n a c o ( h o r r i d l ) - T h u j e t u m p l i c a t a e S p h a q n o ( g l r g e n s o h n i 1 ) - R h l z o m n i o ( p e r s s o n i i ) - L y s i c h t t e t u s i a m e r i c a n l C a m p y M o ( p o l y g a m l ) - C a r l c o ( s i t c h e n s i s ) - S p i r a e o ( d o u g l a s i i ) - M y r t c e t u m g a l l s 6 2 names of the associations, which are shown after the equal signs in Table 6 , may be used for the Latinized names. 1 . PSEUDOTSUGETALIA MENZIESII Krajina 1 9 6 9 The communities of Pseudotsugetalia menziesii, in the study area, are mostly found topographically on ridge top and upper slopes where the habitats are extremely dry (ultra xeric to xeric) and soils are generally shallow. Because of this particular edaphic condition, i t is d i f f i c u l t for Tsuga heterophylla to bacome established. Pseudotsuga menziesii. instead, is the species which is well adapted to such conditions, and therefore, could self-perpetuate on these habitats, constructing the edaphic climax communities. The following is the characteristic combination of species: Pseudotsuga menziesii Hylocomium splendens Amelanchier a l n i f o l i a Trachybryum megaptilum Holodiscus discolor Rhytidiadelphus loreus Festuca occidentalis Two alliances and two associations are recognized in this order. 63 1) FESTUCO (OCCIDENTALIS) - JUNIPERION COMMUNIS MONTANAE* Kojima & Krajina (l) Hylocomio (splendentis) - Festuco (occidentalis) - Juniperetum communis montanae* = the Juniperus communis var, montanae association (Plot 33, 34, 35, 76, 93) (Ref. Table 8, 9, 10) Characteristic combination of species: Constant dominant species: Juniperus communis var. montana Constant species: Festuca occidentalis Hylocomium splendens Important companion species: Hieracium albiflorum Frag aria virginiana Lomatium martindalei Symphoricarpus mollis Pachystima myrsinites This association occurs on extremely dry habitats with excessively drained and shallow s o i l s , surrounding the rock outcrops. The exposure i s predominantly south facing. The slope gradient is high with an average of 20 degrees ranging from 10 to 45 degrees. Parent material is bedrock which is mostly basalt and i t s a l l i e s . The hygrotope of this association is rated as ultra xeric. Soils are so dry and so shallow that the tree layer is com-pletely missing in this association, except for the occurrence of very sporadic stunted individuals of Pinus contorta and Pseudotsuga menziesii. The low shrub layer (B 2) is very well developed, composed almost exclusively Juniperus communis var. montana 64 Table 8, HYLOCOMIO (SPLENDENTIS) - FESTUCO (OCCIDENTALIS) - JUNIPERETUM COMMUNIS MONTANAE No. of P l o t 1 2 3 4 5 P l o t No. 76 93 35 33 34 P l o t s i z e (m2) 9 9 9 9 9 E l e v a t i o n (m) 290 390 440 442 445 Exposure N40E S30E S25E S S10E Average Slope gradient (degr se) 12 45 20 15 10 S t r a t a coverage (.%): A _ _ _ . . . B BO 87 88 60 90 81 C + 10 1 80 80 35 Dh 95 10 70 70 15 52 Ddw - _ _ _ . Dr - - - 18 - 4 Ground coverage (?) : humus 100 100 100 100 100 100 mineral s o i l - - - - -rock - - - - - -decaying wood - - - - - -basal area + + + + + + Number of s p e c i e s : 6 13 15 16 20 14 S t r a t u , S p e N C ( | e s Species Species s i g n i f i c a n c e and s o c i a b i l i t y Presence Average Species S i g n i f i c a n c e By 1 Juniperus communis v a r . montana 9.8 9.9 9.7 8.7 8.7 V 8 . 6 2 Rubus ursinus +.+ _ 4 . 4 II 0 . 8 3 Symphoricarpus m o l l i s - - 2.+ - +.+ II 0.4 4 Rosa gymnocarpa +.+ - - - +.+ II + " C 5 Festuca o c c i d e n t a l i s +.2 +.+ 1.+ +.+ IV 0 . 2 6 Fragaria v i r g i n i a n a - 2.+ - 5.1 4 . 2 III 2 . 2 7 Lomatium martindalei - - +.+ 3.+ 1.+ . 111 0 . 8 8 V i o l a adunca _ +.+ +.+ 1.+ III 0 . 2 9 Hieracium a l b i f l o r u m +.+ - +.+ +.+ - III + 10 Arctostaphylos uva-ursi - - 7.6 9.7 II 3 . 2 11 Antennaria neglecta - - - 6.5 4 . 2 II 2 . 0 12 A c h i l l e a m i l l e f o l i u m s s p . lanulosa - - - 4 . 2 +.+ II 0 . 8 Dh 13 Hylocomium splendens 9.8 1.1 +.+ 4 . 2 3 . 2 V 3 . 4 14 Pleurozium schreberi 4.4 4 . 2 +.+ - III 1 .6 15 Rhacomitrium canescens _ 8.7 5 . 3 - II 2 . 6 16 R h y t i d i o p s i s robusta - - - 6.3 4 . 2 II 2 . 0 17 Trachybryum megaptilum 1.2 3 . 2 - - - II 0 . 8 18 Rhytidiadelphus t r i q u e t r u s 3.2 - - +.+ - II 0 . 6 19 Cladonia r a n g i f e r i n a - - ' 1.1 - II 0.4 20 P e l t i g e r a aphthosa - - +.+ - II + 21 Dicranuro bonjeanii - • - +.+ - +.+ • II + SPORADIC SPECIES: 22 Gaultheria s h a l l on 34 (+.+) Dh 35 Dicranum h o w e l l i i 34 (1 .2) 23 Holodiscus d i s c o l o r 34 (4.+) 36 Rhytidiadelphus loreus 33 (+.+) 24 Pachystima n y r s i n i t e s 35 (+.+) 25 Rosa nutkana 93 (+.+) Dr Hylocomium splendens 33 ( 3 . 2 ) Rhacoroitrium canescens 33 ( 2 . 2 ) 26 A g r o s t i s scabra 93 (2.+) R h y t i d i o p s i s robusta 33 (2.1) 27 Cryptogramma c r i s p a 93 (+.+) 28 Eriophyllum lanatun 93 (3.2) 29 Luzula p a r v i f l o r a 93 (+.+) 30 P e d i c u l a r i s racemosa 93 (+.+) 31 P r u n e l l a v u l g a r i s 33 (+.+) 32 S e l l a g i n e l l a wallacei 93 (4.2) 33 S t e l l a r i a longipes 93 {+.+) 34 T r i e n t a l i s 1 a t i f o l i a 34 (+.+) 65 Table 9. General environment in Hylocomio (splendentis) -Festuco (occidentalis) - Juniperetum communis montanae No. of plot: 1 2 3 4 5 Plot No.: 76 93 35 33 34 Elevation (m): 290 390 kkO kk2 445 Exposure: N40E S30E S25E S S10E Slope gradient (°): 12 45 20 15 10 Climate (estimated): Cfb Biogeoclimatic unit: CWHa CWHb CWHa CWHa CWHa Land form: ledge ridge .... upper slope Relief shape: straight convex straight Drainage extremely v e i l Hygrotope: ultra xeric Parent material: bed rock Thichness of humus (cm): 0-4 0-3 0-5 0-4 0-4 Juniperus communis var. montana. Rarely Symphoricarpus mollis, Rubus ursinus and Rosa gymnocarpa may be present in this layer. Holodiscus discolor. Rosa nutkana. Pachystima myrsinites and Gaultheria shallon were found in only one plot out of five. The occurrence of Symphoricarpus mollis and Rosa nutkana is indicative of dry and base rich edaphic conditions. The herb (C) layer is weakly developed. Festuca occidentalis i s frequently found in this layer. Occasional occurrences include Fragaria virginiana. Lomatium martindalei. Viola adunca and Hieracium albiflorum. In plots 33 and 34, Arcfco-staphylos uva-ursi and Antennaria neglecta show relatively high dominance. The moss layer on humus (D ) is well developed, being dominated by Hylocomium h splendens, followed by Pleurozium schreberi. Rhacomitrium canescens, Rhytidi- opsis robusta, Trachybryum megaptilum and Rhytidiadelphus triquetrus are occa-66 Table 1 0 . General c h a r a c t e r i s t i c s of s o i l s i n Hylocomio (splendentis) -Festuco (occ identa l i s ) - Juniperetum communis montanae Factor un i t of measurement minimum mean maximum pHj A horizon 5 . 2 5 . 6 6 . 0 C horizon 5 . 4 5 . 5 5 . 9 Cation exchange capacity m.eq./lOO g 9 . 6 3 6 . 3 5 8 . 9 Total amount of t calcium eq./cub, m. 6 . 5 7 .2 8 .1 magnesium •i 1.8 2.1 2 . 6 sodium n 0 . 4 4 0 . 8 4 1.23 potassium n 0 . 5 0 0.78 1 . 2 4 organic matter kg/cub. ra. 8 . 3 2 6 . 3 4 8 . 4 nitrogen g/cub, m. 628 1030 1693 a v a i l a b l e phosphorus 0.57 1.90 4 . 3 8 Base saturat ion per cent 2 . 6 15.6 2 4 . 1 Carbon nitrogen r a t i o 7 19 33 F i e l d moisture % on volume basis 10.3 2 1 . 5 3 3 . 5 F i e l d capacity 2 8 . 8 3 2 . 0 3 6 . 6 Sand per cent 7 2 . 0 77 .8 8 2 . 8 S i l t n 1 4 . 8 2 0 . 8 2 7 . 6 Clay n 0 . 0 1.8 6 . 2 sionally found. Cladonia rangiferina and Peltigera aphthosa are common lichens in this association. S o i l texture is coarse. A l l samples collected from the association were loamy sand with one being sandy loam. General characteristics of the soils are shown in Table 10, Generally soils are very shallow with a very thin humus layer. Horizon differentiation is inconspicuous. Soils in the association are classified as Orthic Lithic Regosols, 67 Figure 14. Hylocomio (splendentis) - Festuco (occidentalis) -Juniperetum communis montanae, occurring on an ultra xeric habitat on a south facing rocky slope. Habitat is so dry and s o i l so shallow that no trees occur in this association. (Plot 93, VII 12, 1970) Figure 15. Hylocomio (splendentis) - Festuco (occidentalis) -Juniperetum communis montanae. (Plot 76, VIII 2, 1969) 68 2) GAULTHERION SHALLONIS Kojima and Krajina (2) Hylocomio (splendentis) - Eurhynchio (oregani) - Gaultherio (shallonis) - Pseudotsugetum menziesii = the Gaultheria shallon association (Plot 18, 27, 29, 48 , 6 k t 65, 67, 68, 70, 79, 85) (Ref. Table 11, 12, 13) Characteristic combination of species: Constant dominant species: Pseudotsuga menziesii Hylocomium splendens Constant species: Tsuga heterophylla Mahonia nervosa Chimaphila umbellata Goodyera oblongifolia Rhyt i di adelphus loreus Rhytidiopsis robusta Gaultheria shallon Pinus monticola  Vaccinium parvifolium  Linnaea borealis  Achlys t r i p h y l l a  Eurhynchium oreganum This association occurs on extremely well drained and relatively shallow so i l s . Parent material is mostly g l a c i a l * t i l l and outwash, and partly bedrock. The hygrotope of the association is rated as xeric. The slope gradient of the association is generally high, ranging from 5 to 30 degrees with an average of 17 degrees. The uppermost layer of the forest canopy (A^) is predominantly composed of Pseudotsuga menziesii. rarely accompanied by Tsuga heterophylla. Crown closure is relatively low, with an average cover of F a b l e 11. HYLOCOMIO (SPLENDENTIS) - EURHYNCHIO (OREGANI) - G A U L T H E R I O (SHALLONIS) - PSEUOOTSUGETUM MENZIESII 69 Ho. of P l o t 1 2 3 4 5 6 7 8 9 10 11 P l o t Ho. 67 85 79 65 64 70 63 18 27 48 29 S i z e (IT,2) 400 800 400 400 400 800 800 800 400 800 400 E l e v a t i o n (m) 238 244 259 274 286 290 300 348 400 403 ' • 475 E x p o s u r e N25E S 2 0 « S80E S65E N80E N80E N46E S20E S23W N S25W S l o p e g r a d i e n t ( d e g r e e ) 16 12 10 20 8 12 18 30 30 5 25 Average S t r a t a c o v e r a g e : A 73 75 70 53 70 55 50 48 65 75 75 65 B 98 80 90 70 90 78 98 81 95 90 92 87 C 9 10 12 17 16 ' 4 1 16 39 6 18 13 Dh 62 67 43 61 31 52 67 65 30 84 55 56 D d » 7 2 8 1 2 5 2 + 8 3 ' 4 4 Or - - - 33 52 - + 10 40 2 20 14 Ground c o v e r a g e : humus 85 80 82 58 35 81 90 81 35 90 65 71 m i n e r a l s o i l r o c k d e c a y i n g » o o d b a s a l a r e a Number of s p e c i e s : - - - 35 55 - + 13 50 2 25 16 9 13 11 2 5 13 5 1 10 3 5 7 6 7 5 5 6 5 5 5 5 5 6 39 48 38 38 42 30 32 66 51 50 37 c . , S p e c i e s . S t r a t u m r ^ S p e c i e s S p e c i e s s i g n i f i c a n c e and s o c i a b i l i t y Oh D d » D r 1 P s e u d o t s u g a m e n z i e s i i P s e u d o t s u g a m e n z i e s i i 2 Tsuga h e t e r o p h y l l a 3 T h u j a p l i c a t a Tsuga h e t e r o p h y l l a P s e u d o t s u g a m e n z i e s l I T h u j a p l i c a t a Tsuga h e t e r o p h y l l a 4 C o r n u s n u t t a l l i i T h u j a p l i c a t a 5 P i n u s raonticola 10 11 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 40 43 44 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 69 70 G a u l t h e r i a s h a l l o n V a c c i n i u m p a r v i f o i I urn Mahoni a n e r v o s a Tsuga h e t e r o p h y l l a R o s a gymnocarpa P i n u s m o n t i c o i a A m e l a n c h i e r a l n l f o i i a Rubus u r s i n u s C o r n u s n u t t a l l i i S y m p h o r i c a r p u s at bus L i n n a e a b o r e a l i s A c h l y s t r i p h y l l a C h l m a p h l l a umbel l a t a Goodyera o b l o n g l f o l i a V i o l a s e n p e r v i r e n s T r i e n t a l i s 1 a t i f o l i a P y r o l a p i e t a P o l y s t i c h u m munitum C h i m a p h i l a m e n z i e s i i P y r o l a a s a r i f o l i a A l l o t r o p a v i r g a t a P t e r i d i u m a q u i l i n u m Hypopi t y s monotropa T i a r e l l a t r i f o l i a t a C o r n u s c a n a d e n s i s A d e n o c a u l o n b i c o l o r P e d i c u l a r i s racemosum G a u l t h e r i a o v a t i f o l l a L i s t e r a c a u r i n a Hylocomium s p l e n d e n s E u r h y n c h i u m oreganum R h y t i d i a d e l p h u s l o r e u s R h y t i d i o p s i s r o b u s t a R h y t i d i a d e l p h u s t r i q u e t r u s P l e u r o z i u m s c h r e b e r i T r a c h y b r y u m m e g a p t i l u m Hyl ocomium s p l e n d e n s Hypnum c i r c i n a l e u i c r d i i u m i u i c t j b c e u i . R h y t i d i a d e l p h u s l o r e u s E u r h y n c h i u m oreganum j E l a g i o c h U a : a s p l e n i o i d e s C e p h a l o z i a l e u c a n t h a R h y t i d i o p s i s r o b u s t a R h y t i d i a d e l p h u s t r i q u e t r u s H y l o c o m i u m s p l e n d e n s R h y t i d i a d e l p h u s l o r e u s D i c r a n u m f u s c e s c e n s D i c r a n u m h o i e l l i i E u r h y n c h i u m oreganum R h y t i d i a d e l p h u s t r i q u e t r u s P l e u r o z i u m s c h r e b e r i R h a c p m i t r i u m h e t e r o s t i c h u m Pogonatum m a c o u n i i I s o t h e c i u m s t o l o n i f e r u m Unl urn s p i n u l osum S c a p a n i a a m e r i c a n a B a r t r a m i a p o m i f o r m i s T i rami a a u s t r i a c a H e t e r o c l a d i u m m a c o u n i i H e t e r o c l a d i u n p r o c u r r e n s C i a o p o d i u m b o l a n d e r i A l e c t o r i a s a r m e n t o s a L o b a r i a o r e g a n a Hypogymnia e n t e r o m o r p h a S p h a e r o p h o r u s g l o b o s u s P l a t i s m a t i a g l a u c a D i c r a n u m f u s c e s c e n s I s o t h e c i u m s t o l o n i f e r u m H e c k e r a d o u g l a s i i P o r e l l a n a v i c u l a r s P l a t i s m a t i a s t e n o p h y l l a L o b a r i a p u i m o n a r i a A n t i t r i c h i a c u r t i p e n d u l a F r u l 1 a n i a n i s q u a l l e n s i s A l e c t o r i a s a r m e n t o s a P l a t i . s m a t l a g l a u c a Hypogymnia e n t e r o m o r p h a D i c r a n u m f u s c e s c e n s Hypnum c i r c i n a l e S p h a e r o p h o r u s g l o b o s u s I s o t h e c i u m s t o l o n i f e r u m H e c k e r a d o u g l a s i i L o b a r i a o r e g a n a F r u l I a n i a n i s q u a l l e n s i s P o r e l l a n a v i c u l a r s R a d u l a b o l a n d e r i S c a p a n i a b o l a n d e r i . A n t i t r i c h i a c u r t i p e n d u l a P l a t i s m a t i a h e r r e i H o m a l o t h e c i um n u t t a l 1 i i Hypogymnia d u p l i c a t a Hypnum c i r c i n a l e D i c r a n u m f u s c e s c e n s S p h a e r o p h o r u s g l o b o s u s Hylocomium s p l e n d e n s S c a p a n i a b o l a n d e r i R h y t i d i a d e l p h u s l o r e u s P l a t i s m a t i a g l a u c a E u r h y n c h i u m oreganum I s o t h e c i u m s t o l o n i f e r u m 6 . 7 6 . 7 6 . 7 5 . 6 6 . 6 6 . 7 6 . 6 6 . 7 6 . 7 6 . 6 6 . 7 V 6 . 0 6 . + - 6 . 7 6 . 6 6 . 5 6 . 7 5 . + 6 . + 4 . 7 _ 3 . + IV 4 . 5 - 6 . 7 - - 3 . + - - - 5 . 7 6 . 6 . 6 . 6 I I I 2 . 6 4 . + 4 . + - - - - - - - 3 . + 4 . + II 1 . 4 - 4 . + 6 . + - - 4 . + 5 . + 5 . + 6 . 6 5 . + 4 . 6 IV 3 . 5 2 . + - - 4 . + 5 . + 2 . + - 4 . + 4 . + _ I I I 1 . 8 2 . + - - - - - - - 4 . + 3 . + 5 . + II 1 . 3 7 . 6 4 . + - 4 . + 4 . + 3 . + 6 . 5 3 . + 2 . 5 4 . + 5 . + V 3 . 8 2 . + - 3 . + 5 . + 3 . + - - - - _ II 1 . 2 - - - - - - 3 . + - 2 . 4 2 . + II 0 . 6 - - 1 . + 1 . + - - - - - - - I 0 . 2 7 . 6 8 . 8 9 . 7 7 . 6 8 . 6 8 . 7 7 . 7 9 . 9 8 . 9 8 . 8 8 . 8 V 7 . 9 4 . 4 2 . + 4 . + 4 . 4 5 . 3 4 . 4 5 . 4 3 . + 5 . 6 5 . 4 4 . + V ' 4 . 1 4 . + 3 . + +.+ 3 . 2 4 . 3 4 . 4 +.+ 2 . + 6 . 6 +.+ 4 . 3 V 2 . 7 5 . 5 3 . + +.+ - - +.+ 6 . 6 +.+ 1 . 2 +.+ 1 . + V 1 . 5 +.+ 1 . + +,+ +.+ 2 . + - - 2 . + 2 . 2 - 1 . + IV 0 . 7 +.+ - - 2 . + +.+ 1 . + +.+ - +.+ +.+ +.+ IV 0 . 3 - - +.+ • . + - - - +.+ 2 . 3 - - II 0 . 2 +.+ +.+ +.+ - +.+ - - - - - - II + +.+ ~ +.+ +.+ - +.+ +.+ • • - +.+ _ II II + + 4 . 1 2 . + 3 . + 4 . 1 4 . 2 2 . + +.+ 4 . 1 3.1 2 .1 4 . 2 V 3 . 3 3 . 2 +.+ 4 . 3 3 . + 4 . 3 +.+ - 3 . + 6 . 5 4 . 3 V 2 . 5 +.+ 1 . + 2 . + 3 . + 3 . + 2 . + 2 . 1 2 . + 3 . + 3 . + V 1 . 8 +.+ +.+ +.+ +.+ +.+ +.+ +•+ - - +.+ V + +.+ - - +.+ +.+ +.+ - 1 . + - +.+ I I I 0 . 1 +.+ - +.+ +.+ +.+ - - - +.+ - +.+ 111 0 . 1 +.+ - - +.+' +.+ +.+ +.+ - - - . I I I + - +.+ - - - - +.+ _ +.+ I I I +.+ - +.+ - +.+ +.+ - - _ I I I + +.+ +,+ - - - - - - - +.+ II + - - - +.+ - +.+ +.+ - - - - II + - +.+ - - - - - +.+ +.+ - - II + - - - - - - - +.+ - +.+ II + - 1 . + - - - '- - - 1 . + - - I 0 . 2 +.+ -- -+,+ +,+ +.+ +,+ +.+. +.+ 1 . + I I I I I 0 . 1 + + + + 6 . 6 7 . 6 6 . 6 8 . 6 7 . 7 7 . 7 8 . 7 8 . 6 5 . 6 8 . 6 7 . 6 V 7 . 0 6 . 5 5 . 5 4 . 3 2 . 2 +.+ 2 . 1 4 . 3 3 . 3 +.+ 4 . 2 V 2 . 7 +.+ 1.1 3 . 2 2.1 1.1 5 . 2 3 . 2 1 . 2 4 . 4 5 . 3 1 . + V 2 . 4 3 . 2 3 . 2 - +.1 2 . 1 +.+ 4 . 3 1 . 2 2 . 2 2 . + 3 . + V 1 . 7 - 1.1 - 3 . 2 +.+ + . • +.2 - - 1 . 1 I I I 0 . 5 - 7 - +.1 - - 1.1 - - 5 . 3 - II 0 . 5 3 . 2 ' 1.1 2 . 1 4 . 2 1.1 2 . 2 1.1 +.1 +.+ +.+ +.1 2 . 2 1 . + 1.1 1 . + 2 . 1 1.1 1.1 3 . 2 +.+ 1.1 4 ; 3 ' 1 . 1 1.1 1.1 2 . 2 2 . 3 6 . 3 2 . 1 +.+ 2 . 1 3 . 2 1.1 7 . 4 3 . 2 4 . 4 + . 2 +.+ +.+ 7 . 6 3 . 3 1.1 +.+ 2 . 1 +.+ 1 . 4 1 .1 5 . 3 3.1 2 . 1 +.+ 3 . + 1 . + V V ' _w, V II II I I V V IV IV 1 . + 2 . 1 1 . + 3.1 3 .1 3 .1 3 . 1 +.+ 3.1 3 . 2 2 . 1 2.1 2.1 2 . + 3.1 1 . + 1 . + 2 . + 4 . 2 2 . 1 4 . 2 +.+ 1 . + +.+ +.+ +.+ - +.+ +.+ 2 . + +.+ 1 . + 2 . + 2.1 - - 3 . 1 - 2 . + +.+ 2.1 2 . 1 _ - - - +.+ +.+ - Z.\ _ - 1.1 2 . 1 - - - +.+ 1 . + +.+ +.+ - +.+ +.+ +.+ - - - -2 . 2 1 . + V V V IV I I I II I 1 . 4 1 . 0 . 0 . 2 0 . 3 4 . 3 1 . 7 0 . 4 + 0 . 7 0 . 6 0 . 3 0 . 3 0 . 1 3 . 2 2 . 2 2 . 2 5 . 3 2 . 2 4 . 2 3 . 2 2 . 2 3 . 2 6 . 3 5 . 2 V 3 . 4 +.+ 2 . + 1 . + 3 . + 2 . 1 2 . 2 +.+ 2 . 1 1 . + 3 ; 2 V 1 . 5 +.+ 1 . + 1 . + 2 . + +.+ +.+ 1 . + 1 . + 3.1 3 .1 2 . 1 V 1 . 3 +.+ 1 . + 2 . + 3 . 2 +.+ +.+ +.+ 1 . + +.+ 4 . + 3 . + V 1 . 3 +.+ +.+ 2 . + . +.+ +.+ 2 . + +.+ 3 . 2 3 . 2 2 . 2 V 1 .1 _ +.+ +,+ +.+ +,+ +.+ +.+ +.+ +,+ +.+ +,+ V + _ 3 . 2 3 . 2 +.+ _ _ _ _ 2 . 2 +.+ - I I I 0 . 7 _ 4 . 2 2 . 2 . - - - - 2 . 2 - II 0 . 7 _ +.+ - - - - - - +.+ - II II II + +,+ +.+ +.+ +.+ - : - +.+ +.+ _ + + _ +.+ _ _ _ - - 2 . 1 - I 0 . 2 - - - - - - - - +.+ - I + 3 . + _ +,+ 4 . 2 +.+ 3 . 2 +.+ +.+ - 3 . + +.+ V 1 . 2 +.+ +.+ +.+ 2 . 2 1 . + +.+ +.+ +.+ 2 . + 4 . + 2 . + V 1 . 0 +,+ +.+ +.+ +.+ 1 . + +.+ +.+ +.+ 3 . + 2 . + 2 . + V 0 . 7 „ 1 . + 1 . + +.+ +.+ +.+ +.+ 2 . + Z.* 1 . + 1 . + V 0 . 7 1 . + 1 . + +.+ +.+ +.+ +.+ 1 . + 2 . 1 2 . 1 1 . + V 0 . 7 1 . + 1 . + . 1 . + +.+ - 1 . + 3 . + 3 . + 3 . + IV 1 . 2 +.+ 3 . 2 3 . 2 +.+ - - - 1 . + 1 . + +.+ - IV 0 . 7 4 . 2 3 . 2 +.+ - - - +.+ +.+ - 111 0 . 6 _ 1 . + +.+ +.+ _ _ - 1 . + 1 . + 1 . + I I I 0 . 3 2 . 2 - +.+ +.+ +.+ I I I 0 . 2 _ +.+ +.+ +.+ - - +.+ +#+ - I I I + _ +.+ _ +.+ _ - - - +.+ +.+ - II + _ _ +.+ _ m +.+ - +.+ - II + _ 2 . 1 - - - - - 2 . 1 - I 0 . 3 _ +.+ - - - +.+ - - - I + 2 . 5 2 . 1 0 . 2 0 . 9 0 . 5 0 . 3 + 0 . 2 0 . 1 SPORADIC S P E C I E S : Dh Dds Tsuga h e t e r o p h y l l a 71 A c e r m a c r o p h y l l u m 72 C h a m a e c y p a r i s n o o t k a t e n s l s P i n u s m o n t i c o i a C h a m a e c y p a r i s n o o t k a t e n s i s C o r n u s n u t t a l l i i T h u j a p l i c a t a 73 A b i e s g r a n d i s 74 A c e r g i a b r u m 75 A b i e s a m a b i l i s A b i e s g r a n d i s A c e r g i a b r u m C h a m a e c y p a r i s n o o t k a t e n s i s 76 C l a d o t h a m n u s p y r o l a e f l o r u s 77 P a c h y s t i m a m y r s i n i t e s 78 Rubus s ' p e c t a b i l i s 79 S o r b u s " s i t c h e n s i s 80- V a c c i n w i m a l a s k a e n s e 81 Anemone 1 y a l 1i i 82 C l i n t o n i a u n i f l o r a 63 C o r a l i o r h i z a r s a c u l a t a 84 C o r a l I o r h i z a m e r t e n s i a n a 85 D r y o p t e r i s a u s t r i a c a 86 F e i t u c a o c c i d e n t a l i s 87 F r a g a r i a v e s c a 88 H i e r a c i u m a l b i f l o r u m 89 L i s t e r a : c o r d a t a 90 Rubus p e d a t u s D i c r a n u m f u s c e s c e n s 91 P I a g i o t h e c i um u n d u l a t u m 92 B l e p h a r o s t o m a t r i c h o p h y l l u a 93 C a i y p o g e l a t r i c h o m a n i s 94 C e p h a l o z i a media D i c r a n u m h o w e l l i i 95 L e p i d o z i a r e p t a n s 96 P t i l i d i u m p u l c h e r r i m u m 48 ( 6 . 7 ) D r 85 ( 3 . + ) 97 98 48 ( 1 . + ) 99 65 ( 3 . + ) 48 ( 1 . + ) 100 79 ( 4 . + ) 101 67 ( 2 . + ) 102 67 ( 2 . + ) 103 104 85 ( 3 . + ) 105 29 '(+.+) 79 (+.+) 106 85 (+.+) 48 ( 1 . 4 ) 107 48 ( 1 . 4 ) 108 48 (+.+) 109 27 ( + . 1 ) 110 18 (+.+) 29 ( 1 . + ) 111 112 64 (+.+) 67 (+.+) 27 (+.+) 113 48 (+.+) 114 67 (+.+) 115 64 (+.+) 116 64 (+.+) 117 65 (+.+) 64 (+.+) E B 118 68 (+.+) 119 18 (+.+) 18 (+.+) 27 (+.+) 85 (+.+) 120 27 ( + . • ) 18 (+.+) E C 121 85 (+.+) 18 (+.+) A n t i t r i c h i a c u r t i p e n d u l a C a m p y l i u m h i s p i d u l u m D i p l o p h y l l u m a l b i c a n s Di p i o p h y l 1 u m o b t u s i f o l l a Hypnum c i r c i n a l e -I s o p t e r y g i u m e l e g a n s L o p h o z l a a l p e s t r i s L o p h o z i a b l d e n t a t a L o p h o z i a i n c i s a L o p h o z l a v e n t r i c o s a P e l t i g e r a a p h t h o s a P l a g i o c h i l a a s p l e n i o i d e s P l a g i o t h e c i u m p i l i f e r u m P I a g i o t h e c i um u n d u l a t u m P o h l i a c r u d a P o l y t r i c h u m j u n i p e r i n u m P o l y t r i c h u m p i l i f e r u m R h y t i d i a d e l p h u s s q u a r r o s u s S c a p a n i a b o l a n d e r i S c a p a n i a i r r i g u a Timmia m e g a p o l i t a n a T r a c h y b r y u m m e g a p t i l u m A l e c t o r i a g l a b r a Hypnum s u b i m p o n e n s Nephroma r e s u p i n a t u m P a r m e l i a s a x a t i l i s P e r t u s a r i a ambigens P l a t i s m a t i a h e r r e i D o u i n l a o v a t a H o m a l o t h e c i u m f u l g e s c e n s Hypnum s u b i m p o n e n s L o b a r i a p u i m o n a r i a P a r m e l i a s a x a t i l i s P t i l i d i u m p u l c h e r r i m u m U l o t a megaspora C l a d o n i a o c h r o c h l o r a Hypnum s u b i m p o n e n s N e c k e r a d o u g l a s i i P l a t i s m a t i a h e r r e i P o r e l l a n a v l c u l a r i s P t i l i d i u m p u l c h e r r i m u m 18 (+.+) 18 (+.+) 27 (+.+) 18 (+.+) 64 (+.+) 18 (+.+) 48 (+.+) 18 (+.+) +) 18 ( 18 (+.+) 18 (+.+) 64 (+.+) 18 (+.+) 18 (+.+) 18 (+. 18 (+. 27 (+. 65 (+. 18 (+. 18 (+. 18 (+.+) 48 ( 1 . 1 ) 85 (+.+) 48 (+.+) 18 (+.+) 27 ( + . + ) 70 (+.+) 70 (+.+) 18 ( + 65 (+ 27 (+ 65 (+ 27 ( + 18 (+ 18 (+ 29 (+.+) 79 (+.+) 79 ( 1 . + ) 64 (+.+) 48 (+.+) 48 (+.+) Table 12. General environment in Hylocomio (splendentis) - Eurhynchio (oregani) - Gaultherio (shallonis) - Pseudotsugetum menziesii No. of plot: Plot No.: Elevation (m): Exposure: Slope gradient (°): Climate (estimated): BiogeoClimatic unit: Light intensity (lux): Land form: Relief shape: Drainage: Hygrotope: Parent material Thickness of humus (cm) 1 2 3 It 5 6 7 8 9 10 11 67 85 79 65 6k 70 6 8 18 27 1+8 29 2 3 8 2kk 259 21k 286 2 9 0 300 31+8 l+00q. 1+03 1+75 N25E S20W S80E S65E N80E N80E N46E S20E S23W N S25W 16 12 10 20 8 12 18 30 30 5 25 Cfb •CWH a 1015 2376 2831 311k 1+015 2871 2U93 5051 3021+ 3761+ 5021+ upper ridge ,. upper slope. ridge .upper slope. ridge slope convex straight convex .. straight . convex straight v e i l "bed rock 3 - 5 xenc talus deposits g l a c i a l t i l l and outwash Site index (m/100 years): Pseudotsuga menziesii 37 Tsuga heterophylla 5-10 1+3 37 3-5 38 3-5 23 5-10 10-12 3-5 37 2 1 35 23 21 3-5 30 3-5 1+1 21+ 10 26 17 7-10 35 32 71 Table 13. General c h a r a c t e r i s t i c s of s o i l s i n Hylocomio (splendentis) -Eurhynchio (oregani) - Gaultherio ( sha l lon is ) - Pseudotsugetum menzies i i Factor un i t of measurement minimum mean maximum pH: L-H horizon 4 . 2 4 . 8 5 . 5 A horizon 4 . 7 5 . 2 5 . 8 B horizon 4 . 6 5 . 5 6.1 C horizon 4 . 6 5 . 7 6 . 5 Cation exchange capacityt humus m.eq./lOO g 5 8 . 3 9 9 . 2 167. ( mineral s o i l s it 5 . 3 15.7 4 3 . ! Total amount of t calcium eq./cub. ra. 4 . 5 9 . 3 24 .3 magnesium N i .O 2 . 0 3 . 7 sodium tf 0.68 1.21 1.88 potassium It 0 .42 0.72 1.05 organic matter kg/cub. m. 9 . 0 2 5 . 3 42 .0 nitrogen g/cub. m. 196 402 937 a v a i l a b l e phosphorus 0.47 1.49 2 .91 Base saturat iont humus per cent 10.2 26 .5 3 8 . 6 mineral s o i l s 4 . 1 17.3 40 .6 Carbon nitrogen r a t i o t humus 18 37 62 mineral s o i l s 21 52 103 F i e l d moisture % on volume basis 10.2 15.7 28 .9 F i e l d capacity t« 2 1 . 9 26 .4 3 2 . 7 Sand per cent 76 .7 84 .0 8 9 . 3 S i l t n 8 . 0 12.5 18 .9 Clay tt 0 . 5 3 . 5 9 . 0 I Figure 16. Hylocomio (splendentis) - Eurhynchio (oregani) - Gaultherio (shallonis) - Pseudotsugetum menziesii occurs on upper slopes where habitats are well drained and soils are relatively shallow. Tree growth is rather poor, and trees are so sparse that light intensity under the forest canopy is very high. This is the only association in which Pseudotsuga  menziesii can self-perpetuate forming the xerosere climax community. (Plot 79, VIII 9, 1969) T3 Figure IT. Hylocomio (splendentis) - Eurhynchio (oregani) -Gaultherio (shallonis) - Pseudotsugetum menziesii, occurring on xeric habitat on upper slope. Tree growth is rather poor and trees are sparse. Tsuga heterophylla grows on decaying wood or substra-tum derived from decaying wood. (Plot 1 8 , VIII 15, 1968) Figure 1 8 . Hylocomio (splendentis) - Eurhynchio (oregani) -Gaultherio (shallonis) - Pseudotsugetum menziesii. (Plot 79» VIII 9 , 1969) the A layer being 65%. Therefore, light intensity under the canopy is signi-ficantly high, with an average light intensity of 3239 lux, the highest value among the forested associations in the present study. In the Ag and A^ layers, Thuja plicata is found occasionally, Acer macrophyllum, Pinus contora and Chamaecyparis nootkatensis are also sporadic. In the B-^  layer, Tsuga heterophylla is more dominant than Pseudotsuga menziesii. The habitats, however, are too dry for Tsuga heterophylla to get established and most of those present apparently grow on decaying wood or on substrata derived from decaying wood. Thus, in this association, Pseudotsuga menziesii has an advantage over Tsuga  heterophylla. and this is only the association where Pseudotsuga menziesii would be able to self-perpetuate. The Bg layer is overwhelmingly dominated by Gaultheria shallon. accompanied by Vaccinium parvifolium. Mahonia nervosa, Tsuga heterophylla. Rosa gymnocarpa and Pinus monticola. Due to the high coverage of the B layer, the development of the C layer is rather weak. Cover-age of the C layer ranges from 1% to 39$ with an average of 13%, The dominant species in the C layer i s Linnaea borealis followed by Chimaphila umbellata and Achlys triphylla . Goodyera oblongifolia, although not dominant, shows relatively high presence. Besides the plants mentioned above, Viola  sempervirens, Trientalis l a t i f o l i a . Pyrola picta. Polystichum muniturn and Chimaphila menziesii are occasionally found in this association. The D layer is well developed with 56$ coverage. Hylocomium splendens is the dominant followed by Eurhynchium oreganum. Rhytidiadelphus loreus and Rhytidiopsis  robusta. In addition, Rhytidiadelphus triquetrus and Trachybryum megaptilum are relatively common. On decaying wood, Hylocomium splendens again occurs prevailingly, and Dicranum fuscescens, Rhyt i di adelphus loreus, Hypnum circinale and Eurhynchium oreganum are common constituents. Of the liverworts, Scapania 7 5 bolanderi is very common on decaying wood. Plagiochila asp.lenioides, Cephalozia leucantha, Lepidozia rept an s and Calypogeia trichomanis are found sporadically. In general, liverworts are less developed in this association, probably due to the dryness of the habitats. On rocks, generally the bryo-flora is relatively rich. Forty species are recorded on rocks in this asso-ciation. The dominant species is again Hylocomium splendens, accompanied by Rhyt i di adelphus loreus, Dicranum fuscescens and Dicranum howellii. The occur-rences of Claopodium bolanderi. Heterocladium procurrens and Heterocladium  macounii on rocks indicate that the rocks are rich in. mineral nutrients such as calcium and magnesium (Krajina 1 9 7 1 : personal communication). Epiphytic communities in this association are not very well developed. Alectoria  sarmentosa i s , however, the commonest. Hypogymnia enteromorpha, Sphaerophorus  globosus and Platismatia glauca are commonly found on trunks and branches of conifers. Homalothecium fulgescens and Hypnum subimponens occur frequently on the bark of Acer macrophyllum. Porella navicularis» Radula bolanderi and Frullania nisquallensis are occasionally found growing on the dead material of other mosses. Towards the bases of the trees, the proportion of such humicolous bryophytes increases as for example, Hylocomium splendens, Eurhynchium oreganum and Rhyt i d i adelphus loreus. Productivity of this association is low. Site index of Pseudotsuga  menziesii is 3 3 m/100 years; that of Tsuga heterophylla is 2 6 m/100 years; Thuja plicata i s actually missing in the tree layer of this association. In general, s o i l texture is coarse, and i t appears to become coarser with depth. Most of the soils are loamy sand with some being sandy loam and sand. There is a slight tendency for clay to accumulate in the B horizon, though i t is not enough to be a Bt horizon. General characteristics of the 76 soils in this association are shown in Table 13. In general, the pH value of the humus is as low as !t,8 on the average with a range from k.2 to 5 . 5 . The pH value increases with depth and averages 5 . 7 in the C horizon. Thickness of humus ranges 3 to 12 cm. Cation exchange capacity of the humus layer ranges from 5 8 . 3 to 167.O m.eq. /100 g with an average of 9 9 . 2 m.eq./lOO g, and that of the mineral soils ranges from 5 . 3 to U 3 . 6 m.eq./lOO g, with an average of 1 5 . 7 m.eq./lOO g. Generally, t o t a l amount of extractable cations (calcium, magnesium, sodium and potassium), nitrogen, available phosphorus and organic matter decrease with depth. Base saturation of the soils in the association is low as the average of humus is 21% and that of the mineral soils is 11%. The carbon: nitrogen ratio is relatively wide with an average for humus of 3 7 , and that of the mineral soils of 5 2 . Field moisture is the lowest among the associations with an average of 15.1% on a volume basis. A l l soils examined were found to be Brunisols (Dystric Brunisols). None of them were Podzol which are usually associated eith the Gaultheria type of communities. This association is comparable to the orthic Gaultheria forest type (Orloci 1 9 6 l , 1961+) , but different from i t in the following respects: in this association, l ) complete lack of Holodiscus discolor. 2 ) very low dominance Pteridium aquilinum. 3) occasional occurrences of Trientalis  l a t i f o l i a , T i a r e l l a t r i f o l i a t a and Polystichum munitum. These three species are indicative of rich habitats essentially in bivalent cations which are usually easily removed on such habitats. This probably would be due to the base rich parent material which compensates the loss of these cations, and consequently prevents the developemnt of Podzols in this association. 77 2. TSUGETALIA HETEROPHYLLAE Krajina 1969 The communities of Tsugetalia heterophyllae occupy an extensive area on gentle slopes of h i l l s i d e s and terraces close to bottom of valleys. Hygrotopically they cover a relatively wide range from submesic to subhygric. At the present, the uppermost layer of the forest canopy predominantly consists of Pseudotsuga menziesii due to the rich edaphic conditions which are favorable for the species, especially under the comparative drier climate. However, i t is evident that Tsuga heterophylla competes successfully with the shade intolerant Pseudotsuga menziesii as the humus becomes acid enough, accompanied by the formation of podzols. It would become a dominant species ultimately on these habitats forming the climatic climax communities, since the macroclimate potentially f i t s to the requirement of the species. The following are the characteristic combination of species: Tsuga heterophylla Listera cordata Taxus brevifolia Pyrola secunda Amelanchier a l n i f o l i a Rhyt i di adelphus loreus Cornus canadensis Rhytidiopsis robusta Dryopteris austriaca (Vaccinium parvifolium)* Goodyera oblongifolia (Linnaea borealis) Listera caurina Two alliances and two associations with two variants were recog-nized in the present study area. They are Hylocomio (splendentis) -Pseudotsugo (menziesii) - Tsugion heterophyllae which comprises Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo -Tsugetum heterophyllae, and Vaccinio (alaskaensis) - Abieto (amabilis) -* Species shown in parentheses are the plants which better characterize some other hierarchical units. 78 Tsugion heterophyllae which includes Rhytidiadelpho (lorei) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) -Tsugetum heterophyllae. Both of them are considered to be the closest to the climatic climax communities. The former is of the drier subzone, and the latter is of the wetter subzone. 3) HYLOCOMIO (SPLENDENTIS) - PSEUDOTSUGO (MENZIESII) - TSUGION HETEROPHYLLAE Kojima & Krajina (3) Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae = the moss association (Plot 05, 07, 09, 10, 12, 53, 63, 72, 8 l , 83, 03, 06, 08, 11, l 6 , 19, 28, 31, 1*7, 51, 66, 69, 89) (Ref. Table lk$ 15a, 15b, 16) Characteristic conbination of species: Constant dominant species: Pseudotsuga menziesii Tsuga heterophylla Hylocomium splendens Constant species: Mahonia nervosa Vaccinium parvifolium Linnaea borealis Achlys t r i p h y l l a Chimaphila umbellata Viola sempervirens Goodyera oblongifolia Eurhynchium oreganum Rhyt i di adelphus loreus Important companion species: Pyrola secunda Chimaphila menziesii Table lk. HYLOCOKIO (SPLEKDEK1IS) - EIKHYNCHIO (OREGANI) . HtHOIIIO (KERVOS4E) . PSEUDOTSUGO - TSUCETUI HEIEROPHYILAE 79 •JMIIOSm KEWOSAE HYlOCOalOSIK SPLENDENTIS Ko. of j i l t 1 2 3 t 5 6 7 8 9 10 11 12 13 tt 15 16 17 18 19 20 21 22 23 Plot Jo. 72 61 53 83 63 10 12 05 07 09 51 69 69 66 19 03 11 31 16 06 t 7 08 2 8 . S l u ( a 2 . too 300 too 300 600 600 800 . 600 800 800 too 800 600 too 800 800 800 600 800 800 600 800 600 Elevatlor (3) 23S 2tO 211 268 298 320 32t 350 372 t36 250 253 27t 311 lit 320 326 3t2 357 366 381 39* 121 Eiposura 1 S65E • 5601 S15I S20E StOi sios S16> S35E S S25I I125E S70E S70E S 11103 SISI S26E (20; S20I N20J S S26I Slope gr;j)lent ( d e ; n • ) 1 - 10 18 20 10 5 25 25 25 12 15 1 18 15 5 10 26 20 8 5 22 30 Average Strata cryerage ( I ) : * 75 70 98 95 80 92 92 82 76 85 68 66 75 50 80 90 85 60 95 92 ' 88 95 60 81 9 50 60 95 70 70 73 92 80 60 35 50 25 24 12 t IB 15 58 17 65 65 22 6 18 C 37 21 39 31 12 3t 53 18 2t It 61 2 5 16 3 12 62 26 6 17 18 35 6 21 Oh 3 ! • 3 50 t3 26 16 33 50 56 83 78 73 to 35 16 60 59 7! 88 58 68 36 12 53 Gd. 5 21 15 2 t 10 16 13 9 3 9 13 7 3 12 12 9 2 6 18 1 1 9 Or - - - 1 II - - 2 2 5 - - 15 t6 10 - * 2 1 11 6 33 31 8 Ground ci^erage ( I ) : huaus 90 66 59 86 71 75 73 72 76 80 80 78 59 t l 55 75 7! 80 88 67 66 19 15 70 a t r e r a l s o i l s - - - - - 2 - - 2 - - - - - 3 - - - - 2 - 2 2 * rock _ _ 1 It . 3 3 6 _ 15 53 II - 1 2 1 15 7 37 . 16 10 decaying eood e 26 33 5 7 It 19 15 10 5 12 17 16 1 18 15 16 10 t 7 19 1 5 12 basal area 1 S 3 S 9 6 10 9 9 8 5 8 5 10 10 9 6 7 9 6 6 8 B ouster 0; s p e c i e s : 37 to 12 30 57 tt 38 58 tt t3 tt 33 39 36 to 52 52 to 11 19 11 57 39 11 S t r a t u s Species Species Species s i g n i f i c a n c e and s o c i a b i l i t y Presence 6.7 7.7 6.7 7.7 6.7 7.7 7.7 7.7 6.7 7.7 6.7 5.7 5.7 5.6 7.7 7.6 7.7 3 . . 5 .6 7.7 5 . * 7.7 6.8 _ 6.6 6.7 . 7.7 6.7 7.7 7.7 6.7 _ 6.7 7.7 _ 6.7 7.7 6.7 6.7 7.6 5.7 6.6 7.6 6.7 6 . . 6.7 _ 5 . * _ 1.. _ 1.* 5 . * 6.6 5.7 5.6 1.. - 6.6 5.6 - 5 . . 5.7 - 6.6 - - 3 . - 3.3 3.6 2.6 t.7 t.7 - - 2 . * - - 2.6 1.5 - 1.5 5.6 1.. - -5 . * _ 5 . . 5 . * 5.7 5.6 1.6 5.6 5.7 _ 5 . * 3 . . _ 6.6 1.6 6.7 3 . * 6.5 5.7 5 . 6 6.6 5 . * _ _ - 1.6 3 . . _ 1.. - 6.6 1.6 3 . . t.5 5.7 3 . * t.6 -6 . . Average Species S i g n i f i -cance 49 50 5! 52 53 54 55 55 57 53 59 Pseudotsuga menziesii Ts-jga heterophylla Tsuga heterophylla Pseudotsuga s e n z l e s l l thuja p l i c a t a Tsuga heterophylla Thuja p l i c a t a Cornus n u i t a l l i l Pseudotsuga =er.zlesil Acer sacroph-yllua Tsuga h e i e r o c h y l l a Thuja o l i c a t a Ta*us b w i f o l l a "ahor.ia nervosa V a c c i n i a p a r v l f o l i u a Tsuga heterophylla Gaultheria s h a l l on Rosa gy=nocarpa Vacciniua alaskaense Rubus urslnus • e n z l e s l a ferruglnea MsetancMer a l n l f o l l a Cornus n u t t a l l i l Abies a i a b i l l s Syrphorlcarpus albus Jams b r e v l f o l i a Abies grandls Pinus e o n t l c o l a Sorbus s i t c h e n s i s Achlys t r i p h y l l a Llnnaea boreal Is Chioaphlla u a t e l l a t a V i o l a seapervlrens Goody era o b l o n g l f o l i a Polystlehua uur.i iua Cornus canadensis T i a r e l l a t r l f o l l a t a Chioaphlla a e n z l e s l l S i l l a c i n a s t e i l a i a Pyrola secunda Pyrola pi eta • DisDorua. hookeri Adenoeaulon M col or Lactuca aural i s C o r a l l o r h l z a aaculata Hypooltys lonotropa T i a r e l l a l a c l n l a t a Gallun t r l f l o r u n T r i e n t a l l s l a t l f o l i a CtlntonS a unt f l o r a Blechnua spicant •ono t r oca uri I f l o r a L i s t e r a cordata Dryopterlt tustriaca H t i l to=es co^gesta Hylocoalua splendens Eurhynchlun oreganua Rhytldladelpnus loreus R h y t l d i o p s l s robusia Rhytidiadelphus t r l c u e t r u s Irachybryua aegaptilua P l a g l o i r e d u n undulatua Hnlua spinuloses Dlera"bn fuscescens O l c r a n . s hovel 111 P l a g t o c h l l a asplenloides Isotheciua s t o l o n i f e r u a Kypnua c i r c i n a l e Scapanla bolanderi Olcranus fuscescens Hyloccsiun splendens Eurhynchlua oreganua Rhytidiadelphus loreus tsotheciua s t o l o n i f e r u a P l a g t o c h l l a asplenloides Rhlzo-nlua glabrescens Cephalozia leucantha Cephalozia cedi a Elepharosioaa t r l c h o p h y l l u a Calypogela f l s s a • n l i a splnulosua PtlMdlu-3 pulcberrlnua P t l l l d i u a c a l i f o r n l c u s F r a l l a n i a ni scjuallensls R h y t l d i o p s i s robusta J a s e s o n l e l l a autumnal Is Scapanla u=brosa Lop ho/i a porphyrolexa Lepldozia reptans Hyloco=lua splendens Rhytidladelohus loreus H e t e r x l a d l u a procurrens lsotheclu= s t o l o n l f e r u a Ke'.erocladlua s i c o u n l l P l a g l o c h l l a asplenloldes Rhytldioosis robusta Iscoteryglua elegans R h a c o i i t r l u f i heterostichua ScapaMa a^ r l c a n a Plat;Io=nl ua ln*,lsne D l c o n u a h o * e l l l I Pogonatun cacounl I f l a . ; l o t r e c i u a p l t i f e r u a P o r e l l a cordaeana B a r i r a a l a p c a i f o r s l s Hypr.ua subispo^ens Plagiotheclua denticulatua Olcranua fuscescens Rhytldiadephus t r i c u e t r u s Scapanta bolanderi \\w.\i a u s t r i a c a L o p b x o l e a bldentata Sphaerophorus globosus A l e c t o r l a sarreniosa P l a t i s : a t l a glauca L o t a r i a oregana Hypogy;nla entero^orpha Olcranua fuscescens Isotheclua s t o l o n i f e r u f l Hypnus c i r c i n a l e F r u l l a n l a n l s q u a l l e n s l s Nec^ara douglasii F I a t i s = a t l a stenoohylla S c a p u l a bolanderi P o r e l l a n a v l c u l a r l s Sphaerophorjs globosus Oicranua f'-scescens H>'pr.u-! c i r c i n a l e Isothecl'js s t o l c n i f e r u a P l a t i s = a t i a glauca fypogy^.ia enterosorpha Scapanla bolanderi rWcVcra d o i . ^ l a s l l F r u l l a n l a n l s q u a l l e n s l s P o r e l l a n a v l c u l a r l s A l e c t o r l a sar-entosa Eurhynchiua oreganua liec^era w m i e s H P t i l i d l u n pulcherrtcus P l a g i o c h l l a asplenloides Polypodlua g l y c y r r h l z a Qicranua fuscescens ^,-pnua c i r c i n a l e Scapanla tolanderl Rhytidiadelphus loreus Hylocoaiua splendens Eurhynchiu" oreganua I s o t h e d u - : s t o l o n l f e r u a Sphaerophorus globosus !«c>era do'jglastt Cladonia conlocraea P l a g l o c h i l a asplenloides Rhytidiadelphus t r i g u e t r u s P o r e l l a n a v l c u l a r l s Lcphocolea heterophylla Keel era c e r . i l e s l l Lepldozia reptans H e t e r t x U d l u ^ procurrens P t i l i d i u a pulcherriBua Claopodiu; bolanderi 5 . 3 3'.1 3.2 7.6 3.2 2.2 6 . 3 1.4 3.3 5.6 5.6 5 . * 5 . * 5.5 M * . 4 * . * A . * 5.5 5.4 4.3 5.5 6.5 7.5 4.3 5.4 B.6 4.3 5.5 6.5 3.2 3.2 4.3 1.1 +.2 1 . * 2.2 +.1 6.4 2.2 1.1 2.2 1.1 6.6 5.6 1.3 5.5 6.5 6.4 4.3 3.3 5.5 *.1 +.1 6.4 4.3 6.6 5.4 5.5 4.3 1.1 1.1 1.2 +.1 7.6 3.2 5 . 3 2.1 5.6 4.5 4.5 4.4 5.3 6.4 3.2 4.2 1.+ 5.2 4.2 2.2 1.2 3.3 5 . 3 2.2 1.1 •.1 2.2 4.2 3 . 2 1.2 4.2 4.3 3.2 1.2 2.3 3.2 2.2 •.1 1.+ 3.2 2.2 2.2 3 . 2 3.3 4.3 3.3 1.2 1.1 3.1 2.2 - 1.2 3.2 3.3 2.2 1.2 2 . 3 4.2 3.2 2.2 2.1 1.1 1.2 1.1 1.1 2.1 » 1.1 *.1 1.1 +.1 1.1 +.+ *.+ 1.1 1.2 1.2 1.2 1.1 2.2 1.1 2.2 1.2 4.3 1.1 +.+ _ . +.1 - - 3.2 2.2 1.2 +.+ •.1 +.1 +.1 +.1 1.2 *.l 1.1 +.* +.+ 1.+ - 1.1 +.+ 1.1 1.2 •.1 _ +.* +.1 1.1 1.1 +.1 +.+ +.* - * .1 •.• - •.1 +.+ - -. 3.2 •.+ •.1 +.1 +.+ +.+ +.* - 1.1 +.2 - +.2 - +.1 +.2 +.+ - -+.1 1.+ _ 1.2 - - - - +.+ +.• - - - - 1.2 - - - - 1.1 2.1 • 1.2 1.1 - - - - +.* - - - - - - - - - - " _ 1.2 +.* _ _ - - - +.* - - - - - - - - -_ _ , _ _ _ _ +.+ - *.* - *.+ _ _ _ +.+ - •.+ - - - -_ _ _ *.+ - - +.+ - -'_ _ - - - - - +.* - - *.+ - - - -+.1 _ *.+ - - - - - - - - - - +.+ - - - *•* 2.2 3.3 2.3 1.3 +.1 • . • . 1.1 1.1 2.2 +.+ *.+ - +.+ 4.3 7.4 3.3 3.3 1.1 1.2 1.2 2.1 3.2 •.• --1.1 *.+ 1 . * 1.+ •.* 2.2 * . * 1 . * 3.2 2.2 1.1 2.1 1.1 1.1 1.1 4.1 3.2 +.• 4.2 2.2 * . * 1.1 1.1 1.1 1.1 1.+ 2 . * 1 . * 3.2 *.* 4.2 1.1 1.1 1.1 *-.+ 1.1 3.2 1.1 1.1 2.2 *_* *.+ 1.1 2.1 +.* +.+ *.+ 3.2 •.+ 1.1 1.1 • . • 2.1 1.1 4.3 +.+ * . * 1 . * _ * . * +.+ 1 . * 2 . * 1.1 _ +.+ 2.2 - 1.1 2.2 1.1 +.+ 1.1 - 3.2 1.1 1.1 *.+ +.* 1.+ +.+ +.+ +.+ 2.1 2.1 +.+ +.+ 2.1 - - *.+ 2.1 1.1 4.2 +.«• _ _ +.* 1.1 1.1 *.+ 1.1 1.1 +.* - •.* 1.+ - +.+ +.+ +.+ +.+ +.+ 3.2 1.1 2.1 +.+ . 2.1 * . * . 1.2 - - - - 2.1 2.+ - +.+ _ _ *.+ _ 1.1 2.1 1 . * _ - +.+ - 1.+ +.+ - +.• 1.1 - - - - - . 1.1 - - - - - *.+ - - - - - *.+ 1.+ -2.1 1.* 3.1 3.1 3.1 1.1 ... 2.1 1.1 2.1 3.2 1.1 3.2 3.2 3.2 1.1 2.1 1.1 2.1 2.1 2.2 1.1 2.1 +.+ 1.+ 2.2 1.1 2.1 2.1 3.2 2.1 2.1 2.1 1.1 2.1 * ' * 1.+ _ 2.1 +!• 4.2 3.2 2.1 2.1 1 . * - - 1.+ 1.1 1.* 1.1 2.2 2.2 2.1 2.2 2.1 1.1 1.1 *.+ 4.2 3.2 3.2 +.+ +r+ 2.1 1.1 2.2 - +.+ - 1.+ 1.* -1.+ 1.+ -*.+ *.+ +.+ +.+ 2 . * 1.* • *.+ 2.1 3.2 - +.+ 1.+ - +.+ 3.2 - +.+ . _ _ . +.• *.+ - +.+ - +.+ *.+ 3 . f *.* *.• „ •.* •.* •.* 2.1 *.+ • . • - +.+ • . • - - - -4.2 1.1 1.1 - - 4.2 - - - - - - - - - -- - 1.1 1.1 - •.* *.* 3.2 - - • III III III II 6.1 0.8 5 . 0 3.3 2.0 1.0 1.6 0.7 0.2 0.2 3 . - t.. 5.6 3 . ^ 3.6 2.5 1.6 3.5 5.6 5 . » 3 . . _ 1.6 2.6 1.5 2 . » 5.7 t.» t.5 1.» V 3.1 II 0.7 1 0.1 7.7 7.6 7.7 8.5 7.6 7.6 7.t 5.5 6.1 6.1 t.5 3.3 3.2 3 . 2 » . 3 t.l 1.3 1.3 2.5 1.3 t.l 2.3 V 1.3 2 . * 2 . » 3 . * t.. 5.5 5.1 3.t 1.1 3.1 1.1 1.* 5.1 - 3.1 5.5 7.7 5.1 5.5 6.5 3.1 1 . . V 3.3 3.5 1.. +,* 1.5 6.5 1.5 5.1 1.3 5.5 3.3 *.+ - 1.1 1.5 t.l 2 . . 1.1 t.5 2 , » 3.1 V 2.3 2.1 +.+ +.+ «.l 1.5 t.3 2.1 - +.+ • - 3 . 3 - - 2.1 2.t 5.5 t.l • . 3 - IV 1.3 1.+ 1 . . 3 . . _ . . 3 1.3 1 . * • . 3 3 . * - - •.+ - - • . 2 1 . « - - - 1.3 - IV 0.1 1 _ 3.5 t.t J.t 3.1 1 . * - - 2 . * - - 3.1 1.1 - 3.t t.5 - 1.3 - III 1.3 _ ... . _ . . 3 • . 3 _ +.• - - - - - - - III + _ _ 3.5 3.t 2.1 1.3 - _ - - - - 1.3 - - - - - 1.3 II 0.5 - - - - - 1 . * 1 . * - - - - - - - - - - II 0.1 0.2 0.1 0.1 0.1 0.1 6.5 3.2 6.5 4.3 4.2 5.3 6.2 3.3 5.3 3.3 5.5 1.+ 1 . * 1.3 •.+ 4.3 5 . 3 - 2.2 2.2 1.3 1.3 V 3.2 1 . * 5.2 2.+ 3.1 3.2 1.1 3.2 2.2 3.2 6.5 •»•.+ 3.+ 4.1 * .1 3.2 5.2 1.1 3.2 4.1 4.1 3.2 1.3 V 2.7 : +.* _ 1.2 5.2 2.2 1.2 3.2 +.+ +.+ •.* I.* • . 2 *.+ 6.2 2 . * 2 .2 4.1 3.1 1.2 ... V 1.5 _ +.* +.+ +.+ 1.2 1.1 *.1 ..1 1.1 +.+ *.+ - +.1 *.+ 1.1 1.+ - 1.+ ..1 1.1 V 0.3 _ *.+ +.+ *,+ _ *,+ ... _ *.+ +.* •.• +.+ 1.1 +.+ •.+ ... +.+ V 0.1 3,3 3.3 •.+ 2 . * 1.+ ..3 *.3 •.2 2.3 1.3 4.4 +.+ - - 1.3 - - • •.1 +.+ 3.3 1.. IV 0.9 _ +.+ _ +.* 1.2 3.2 _ 2.1 1.2 - - - 1.1 4.2 4.1 - 3.1 3.1 3.2 ... IV 1.3 2 . * 1 . * 1.+ ..2 3.2 2.2 1.2 . 1 . * - - * . 2 +.3 +.2 - - +.1 - 3.2 2.. IV 0.7 *.* _ *.+ * . * . •.1 •.1 1.1 •.! +.+ - - +.* +.+ - 1 . * *.* - •.1 ... IV 0.1 _ 3.2 _ 1 . * •.2 1.2 +.1 ... - - - • - - +.+ • . 2 - - - - - v ... III 0.2 _ ..1 -.1 _ _ _ _ _ +,+ +,+ 1.1 ... - III 0.1 III II II 0.2 0.1 - - - ... - ... - - ... ... - - - ... - II II II + +.+ _ _ _ *.+ - - - - - - - - ... II * +.* _ 1 . * - - - - - - - - - - ..2 - II * *'.* 1 . * - - +.+ - - - - - - - - - 1 0.1 0.1 0.1 5.6 3.9 3.3 2.7 0.5 0 . 3 0.2 0.1 0.1 2.6 2.1 0 . 9 0.6 0.3 0.2 0 . 3 +.* 1.3 +.2 4.5 3.3 6.4 7.4 V 2.9 *.+ 1.1 +.2 3.4 2.2 4.4 4.2 V 2.3 •.• - " * 4.2 4.4 V 1.0 1 . 1 i.t l . l t.t 1. U.D +.+ +.* 2.2 - IV 0.4 - *•.+ 1.1 1.1 2.2 tv 0.3 +.+ +.+ IV • •.1 _ 1.1 1.2 i l l 0.3 1.+ 1.* - l i t 0.1 •.1 - +.+ 1.1 III 0.1 _ +.+ +.+ III + _ _ _ 1.1 II 0.1 +.1 - II 0.1 +.«. _ 1.+ - II 0.1 _ l l + _ _ _ It _ _ _ II + _ _ _ II + _ _ _ - II • l i • 0.8 0.8 0 . 6 0.2 0.1 0.3 0.1 0.1 1.6 1.1 l.l 0 . 9 O.t O.I 0.1 0.1 O.t 0.1 O.t - - - - - - - - 1 + 2.1 2.1 2.1 2.1 2.1 5.2 3.2 4.2 4.2 2.1 3.2 2.2 2.2 2.2 3.2 4.2 4.2 4.2 4.2 4.2 1.1 2.2 2.1 V 3.3 3.2 3.2 i.r 2.1 3.2 4.2 2.1 4.2 3.2 3.2 3.2 3.2 3.2 3.2 2.2 5.2 3.2 3.2 3.2 4.2 3.2 3.2 3.2 V 3.1 +.* . 1.1 1.1 +.+ 2.1 1.1 3.2 2.1 2.1 1.1 1.1 1.1 1.1 3.2 2.2 3.2 2.2 +.+ •.+ +.• 1.1 V 1.2 + > * 1.1 1.1 _ +.+ +.+ 4.2 1.* 1.+ *.* +.+ - - +.+ 1.* - - +.+ 2.* 2.* 1.* •.+ IV 0.6 . 1.* _ _ 1.* *.• 1.1 +.+ 1.1 - 2.1 2.1 2.1 - 1.* - - III 0.5 2.* 1.* +.+ •.+ _ - * . • +.* +.+ 1.+ - - - - - +.+ - - III 0.2 2.1 •.+ +.+ • . • +.+ - +.+ - - - - - - - +.* - - III 0.1 +.* 1.* •.+ - - +.+ - - - - •.+ • . • - - III 0.1 _ - - - +.+ 1 + SPCCJ0IC SPECIES »1 Pinus BOr-tiCOla 31 ( 5 . . ) Ihuja p l i c a t a 17 (7.71 ib ies a a a b l l t s 16 (5.5) t i l e s grardls 51 ( 1 . . ) I s l e s a s i t l l l s 16 (2.2) Taius b r e v i f o l i a 06 ( 2 . * ) t b l e s a s a b l l i s 63 ( ! . • ) 99 * c e r glatrua 09 ( 1 . . ) 100 Oplopanax horridus 72 ( 3 . . ) 101 Rlbes d l v a r l c a t u a 0B ( . . . ) 102 Rubus c e c t a b l l i s 09 ( . . . ) 103 A c h i l l e a n i l l e f o l l u s s s p . l a m i l o s a 66 ( . . . ) 101 tctaea rubra 63 ( . . . ) 105 tdiantun sedatuo 63 ( 1 . . ) 106 Anenore l y a l l i l 51 ( . . . ) 107 t t b y r i u a f l l l « - f e : l n a 05 ( . . . ) 106 Bronus v u l g a r i s 51 ( . . . ) 109 Oantbor.la spicata 66 ( . . . ) 110 D i s p o r j * hocVeri 08 ( . . . ) 111 festuca o c c i d e n t a l i s 66 ( . . . ) 112 festuca s u b u l l f l o r a 51 ( . . . ) 113 Fragarta vesca 5! ( . . . ) 1 H Gal 1.3 t r l f l o r u a 51 ( . . . ) 115 Gysnocarplun drycpterls 61 (l.l) 116 Hleracluq a l b l f l o r u a 89 ( . . . ) 117 Latbyrus revadensis 51 ( . . . ) IIS L i s t e r a caurina 31 ( . . . ) 119 L c n l c e r a c i l l o s a 51 ( 2 . . ) 120 Lycopcdiu: clavat'ja 03 ( . . . ) 121 Valantrenua d l l a t a t u a 10 ( . . . ) 122 P t e r i d l u i a g u l l l n u a 07 ( . . 2 ) 123 Pyrola a s a r l f o l l a 16 ( . . . ) 121 Streptopus a a p l e ' l f o l l u s 19 ( . . . ) 125 Streptopus roseus 06 ( . . . ) 126 I r l s e t u a canescens 66 ( . . . ) Blepbarostoaa t r l c b o p h y l l u . 06 ( . . . ) =A ll! A n t l t r i c h l a curtlpendula 06 ( . . . ) Heterocladic^ procurrens 06 ( . . . ) 113 Cladonia souaaosa 17 ( . . . ) 127 Leucolepls o e m l e s l l 08 ( 1 . 2 ) Claopodiua bolanderi 53 ( . . . ) Lophoila bldentata 06 ( . . . ) • 111 Dendrcalsia a b l e t l n a 53 (1.2) Hnlua splnulosuo 08 ( . . . ) 115 Dounla ovata 06 ( . . . ) 128 Pteurozlua schreberl 65 ( 1 . 3 ) 116 Hypogycnia Isshaugil 53 ( . . . ) Rhiio=nlua glabrescens 06 ( . . . ) Neckera cenzlesl i 51 ( 1 . » ) 129 Rhlzoanlua pseudopunctatua 08 ( . . . ) P l a g t o c h l l a asplenloides 61 ( . . . ) 130 11 117 P l a t l s a a t l a berrel 53 ( . . . ) Calypogela sueclca ( . . . ) 118 P o r e l l e cordaeana 51 ( . . . ) 131 Cephalotla bicuspldata 03 ( . . . ) P t l l l d i u a pulcberrlaua 28 ( . . . ) 132 Cephaloila lacaerslana 03 ( . . . ) Radula bolanderi 05 ( . . . ) f r u l l a n l a n l s q u a l l e n s l s 06 ( . . . ) 133 Jungeroannla lanceolata 89 ( . . . ) £B Blepbarostona t r l c h o p h y l l u a 81 ( . . . ) Lophocolea beterophylla 11 ( . . . ) Cephalozia leucantha Bl ( . . . ) 131 Lopbozla I n c l s a 89 ( . . . ) Claopodiua bolanderi 53 (1.1) Neckera douglasii 06 ( . . . ) Dendroalsla a b l e t l n a • 53 (2.1) Plaglonnlun Inslgne 17 ( . . . ) 119 Horaalotheclun n u t t a l l i l 53 (1.1) Pteurozlua schreberl 66 ( . . . ) Hytocoalua splendens 51 (1.1) Pogonatuo aacounll 07 ( . . . ) lobar! a oregana 63 ( . . . ) 135 Rlccardla l a t l f r o n s 03 ( . . . ) Hnluo splnulosuo 05 ( . . . ) Irachybryua aegaptilua 63 ( . . . ) P o r e l l a cordaeana 51 ( . . . ) 19 P t l l l d i u o c a l l f o r n l c u a 09 ( . . . ) 136 Aablystegla serpens ( . . . ) Radula bolanderi 06 ( . . . ) 137 Barbilophozla batcher! 19 ( . . . ) • Rhytidiadelphus loreus 07 ( . . . ) Cephalozia leucantha 66 ( . . . ) 138 DlplophylIua albicans 08 ( . . . ) f i - Cephalozle leucantha 51 ( . . . ) Hypnua c i r c i n a l e 05 ( . . . ) T r u l l e n l a n l s q u a l l e n s l s 83 ( . . . ) Leucolepis o e n z l e s l l 06 ( 2 . 2 ) Lophocolea bldentata 05 ( . . . ) 139 " a r s u p e l l a ererglnate 69 ( . . . ) Plagiotheciua dentlculatua 66 ( . . . ) 110 " e t z g e r i a pubescens 09 ( . . . ) P l a t l s a a t l a glauca 69 ( . . . ) Plagiotheciua undulatua 05 ( . . . ) P o r e l l a cordaeana 5t ( . . . ) Pteurozlua schreberl 66 ( 1 . 3 ) 150 P o r e l l a r o e l l l l 06 ( . . . ) l i t Radula bolanderi 66 ( . . . ) P t l l l d i u a c a l l f o r n l c u a 03 ( . . . ) Rblzoanlua glabrescens 08 (1 .1) Radula bolanderi 05 ( . . . ) Scapanla uabrose 05 ( . . . ) Rhytidiadelphus loreus 16 ( . . . ) Irachybryua aegaptilua 66 (...) Scapanla uabrosa 05 ( . . . ) Trachybryua aegaptilua 09 ( . . . ) Table 15a. General environment in Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae mahoniosum nervosae No. of plot: 1 2 3 1+ 5 6 7 8 9 10 Plot-No.: 72 81 53 83 63 10 12 05 07 09 Elevation (m): 2 3 8 21+0 21+1+ 2 6 8 298 320 32l+ 350 372 1+36 Exposure: S65E S60W S1+5W S20E Sl+OW Sl+OW si+6w S35E S Slope gradient (°): 8 - 10 18 20 10 5 25 25 25 Climate (estimated): Biogeoclimatic unit: Light intensity (lux) Land form: Relief shape: Drainage: ••• Hygrotope: Parent material: ••• Thickness of humus (cm): 3-5 Cfb 1 6 0 2 1 9 l * 0 h i l l s i d e ... straight , CWHa 2012 857 1287 855 677 ... base of slope ...... ... straight f l a t moderate mesic ... submesic .... glacial t i l l and outwash 5 5-7 5 3-5 8-10 5-10 CWHb 2 6 0 6 291+6 1 7 2 8 ... upper slope .. .... well .. .... subxeric 5-10 5-10 7 - 8 Site index (m/100 years): Pseudotsuga menziesii  Tsuga heterophylla  Thuja plicata 1+3 1+1+ 1+3 1+1 1+6 1+6 1+1 1+0 1+1+ 1+6 _ _ 38 21 33 1+1+ 1+1+ 1+1 37 1+1 - 1+3 _ - 1+0 32 21+ 30 1+0 33 Table 15b<General environment in Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae hylocomiosum splendentis Ho. of p l o t : Plot So.: Elevation (m): Exposure: Slope gradient (°): Climate (estimated): Biogeoclimatic u n i t : Light i n t e n s i t y ( l u x ) : Land form: R e l i e f shape: Drainage: Hygrotope: Parent material: Thickness of humus (cm): S i t e index (m/100 years): Pseudotsuga menziesii  Tsu-a heterophylla  Thu.la p l i c a t a 11 12 13 IU 15 16 17 18 19 20 21 22 23 51 69 89 66 19 03 11 31 16 06 1.7 0 8 28 250 253 . 27H 311 3 l U 320 326 3H2 357 366 381t 39I1 H21 S25W N25E S70E S70E S NHOW S15W S26E N20W S20W N20W S S26W 12 15 It 18 15 5 10 26 20 8 5 22 30 CWHb lit lt6 1181 2379 288U 9U8 2132 2631 1838 109 It 2633 1279 126b 2050 a l l u v i a l ,. h i l l s i d e . .. base of slope.. h i l l s i d e talus h i l l s fan straight undulating well mesic alluvium g l a c i a l t i l l and outwash 5-8 8-10 8-10 5 10-15 5-8 5-10 5 s l i g h t l y straight concave undulating. 1.3 Hi H3 H3 38  33 53 Ho 35 H3 H3 38 H5 Ho 37 37 23 3-5 37 37 33 8-10 H3 H3 37 10 2H 29 29 slope straight s l i g h t l y convex colluvium g l a c i a l 6-8 5-6 H3 37 H6 32 CO 82 Table 16, General characteristics of soils in Hylocomio (splendentis) -Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo -Tsugetum heterophyllae Factor unit of measurement minimum mean maximum pHt L-H horizon 3 . 9 4 . 6 5 . 7 A horizon 4 . 1 5 . 2 6 . 0 B horizon 4 . 6 5 . 5 6 . 2 C horizon 5 . 0 5 . 7 6 . 3 Cation exchange capacityj humus m.eq./lOO g 3 3 . 5 100.2 173.0 mineral soils 4 . 1 17.8 4 7 . 3 Total amount oft calcium eq./cub. m. 3.1 13.4 3 9 . 7 magnesium it 1.0 2 . 7 6 .5 sodium •t 0 . 4 8 1.38 2.74 potassium « 0.23 0 . 8 0 1.58 organic matter kg/cub. m. 13 .0 2 5 . 0 4 3 . 0 nitrogen g/cub. m. 294 4 6 1 925 available phosphorus 0.37 2.31 5 .68 Base saturation! humus per cent 13.8 2 8 . 8 6 0 . 0 mineral soils u 5.1 2 3 . 7 131 .6* Carbon nitrogen ratioj humus 17 34 51 mineral soils 8 34 90 Field moisture % on volume basis 8.1 15.9 2 3 . 4 Field capacity tt 9 . 0 2 5 . 0 3 3 . 5 Sand per cent 7 4 . 9 8 4 . 0 91 .8 Silt n 5 . 2 11.9 1 8 . 7 Clay 0 . 9 4 . 1 7 . 8 * probably the result of free carbonate in the soil On mesic habitats on h i l l s i d e , Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae develops. At the moment, Pseudotsuga  menziesii is the dominant tree, but i t would be replaced by Tsuga heterophylla as the l i f e span is terminated, provided that the depauperation of the soils is well advanced approaching the stage of podzols. This association is considered to be the closest to the climatic climax communities. (Elk River Valley, IX 5, 1969) 84 This association develops on well drained mesic habitats where the precipitation i s a major source of water supply (Orloci 1964). Topographic-a l l y , i t occurs on moderate slopes with an average slope gradient of 14 degrees ranging from 0 to 30 degrees. Parent material consists of glacial t i l l and outwash. Soils are relatively deep. This association covers extensive areas on hillsi d e s throughout the study area. The uppermost layer of the forest canopy is predominantly composed of Pseudotsuga menziesii rarely accompanied by Tsuga heterophylla. In the layer, Pseudotsuga menziesii becomes less dominant and in the A^ layer i t is almost missing. Tsuga heterophylla. on the other hand, shows high dominancy in the Ag and layers. Thuja plicata may be occasionally present in both layers. Crown closure of the association is high with an average of cover of 85$. Consequently the light intensity under the forest canopy is low with an average of 1750 lux. The B.^  layer consists mainly of Tsuga  heterophylla and Thuj a plicata with a sporadic occurrence of Taxus brevifolia. The Bg layer is well developed and dominated by Mahonia nervosa. Vaccinium  parvifolium and Tsuga heterophylla are constantly present in this layer. Gaultheria shallon frequently occurs in this layer, but i t s coverage in this association is very low. The occurrence of Rosa gymnocarpa is frequent. Vaccinium alaskaense may be present when precipitation is high. Rubus ursinus, Amelanchier a l n i f o l i a and Menziesia ferruginea are sporadically found. The coverage of the B layer is kh% on the average. The C layer is not well deve-loped, and has only an average coverage of 23%. Achlys t r i p h y l l a is the constant, although i t s species significance is not high. Linnaea borealis. Chimaphila umbellata. Viola sempervirens and Goodyera oblongifolia constantly occur. The frequent occurrences of Polystichum munitum. Ti a r e l l a t r i f o l i a t a 85 and Smilacina stellata indicate the richness of the habitats. Chimaphila  menziesii and Cornus canadensis are also common in this association. Viola  sempervirens and Chimaphila menziesii are highly associated with this asso-ciation, and Pyrola picta, Pyrola secunda and Corallorhiza maculata have also high a f f i n i t i e s to this association. As pointed out by Krajina and Spilsbury ( 1 9 5 3 ) , Becking ( 1 9 5 1 * ) , the concentration of saprophytic plants in this community type is a noticeable feature. These saprophytes include: Allotropa  virgata. Corallorhiza maculata. Hemitomes congesturn. Hypopitys monotropa and aphyllous forms of Pyrola species. The D layer on humus is very well deve-loped, forming a complete carpet-like moss layer on the ground surface. Coverage is 51$ on the average. Hylocomium splendens is the dominant followed by Eurhynchium oreganum and Rhytidiadelphus loreus. A l l of them are characteristics of this association. Rhytidiopsis robust a i s also found frequently in this layer. Other occasional companions include Rhyt i di adelphus  triquetrus. Trachybryum megaptilum anf Plagiothecium undulatum. Orloci ( 1 9 6 1 , 1964) recognized Plagiothecium undulatum as the domi-nant species in the orthic Plagiothecium forest type which developed on mesic habitats as a climax community in the drier subzone of the coastal western hemlock zone. In the present study area, however, the moss type community which develops on almost similar hygrotope to those of the orthic Plagiothecium forest type, is apparently dominated by Hylocomium splendens. and Plagiothecium undulatum is a relatively less important constituent. This • would be also due to the rich edaphic conditions caused by rich parent material and consequent less acid humus condition, since Plagiothecium undulatum is well adapted to a strongly acid substratum which is usually in the form of mor. In the study area, Plagiothecium undulatum is rather commonly found in the 86 Vaccinivim alaskaense association. On decaying wood, Hypnum circinale is the dominant, always associated with Scapania "bolanderi and Dicranum fuscescens. These three species are the most common throughout the association on decaying wood. Hylocomium splendens and Eurhynchium oreganum are also frequent on decaying wood. On rocks, Hylocomium splendens and Eurhynchium oreganum are again the dominants, followed by Rhyt i di adelphus loreus and Mnium spinulosum. The frequent occurrences of Claopodium bolanderi. Heterocladium macounii and Heterocladium procurrens are indicative of the richness of the rocks in mineral nutrients. Epiphytic layers are moderately developed with Alectoria  sarmentosa as a dominant on branches of conifers, particularly in the E^ layer. Sphaerophorus globosus and Hypogymnia enteromorpha are also constantly present on the tree trunks. Of the bryophytes, Hypnum circinale. Dicranum fuscescens and Scapania bolanderi frequently occur on bark and they increase toward the bottom of the trees in the EQ layer. Isothecium stoloniferum is frequently hanging on branches. Frullania nisquallensis. Neckera douglasii and Radula  bolanderi are occasionally found in this layer. In the EQ layer, the propor-tion of humicolous mosses such as Rhytidiadelphus loreus. Eurhynchium oreganum and Hylocomium splendens increases. Productivity of this association is higher than that of the Gaultheria shallon association but lower than that of the Achlys - Polystichum association. Site index of Pseudotsuga menziesii is kO m/100 years; that of Tsuga heterophylla 37 m/100 years; and that of Thu.la plicata 32 ra/100 years. Soils are generally coarse in this association, as three quarters of the examined samples were loamy sand with the rest of them being sand. The coarseness tends to increase with depth. In the B horizon, there i s a slight tendency toward an accumulation of clay, though i t i s not as conspicuous as 87 in the Gaultheria shallon association nor developed enough to meet the requirements to be a Bt horizon. General characteristics of the soils in the association are presented in Table l6. Generally, the pH value of humus is low with an average of U.6 ranging from 3.9 to 5.7. The pH value increases with depth and that of the C horizon is 5.7 on the average. Cation exchange capacity and carbon-nitrogen ratio decrease with depth. The average total amount of available phosphorus is the highest in this association. Most of the examined soils were found to be Brunisols (Dystric Brunisols) with only one case to be Podzol. i Figure 20. A typical s o i l profile in Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae)- Pseudotsugo - Tsugetum hetero-phyllae. A strong reddish color in B horizon is a conspicuous feature. In this association, soils were found to be mostly Brunisols which were homologous to the "pararendzina" soils of Kubiena. 88 Two variants are recognized in this association, i.e. i) mahoniosum nervosae, and i i ) hylocomiosum splendentis. i) mahoniosum nervosae (Plot 0 5 , 0 7 , 0 9 , 1 0 , 1 2 , 5 3 , 6 3 , 7 2 , 8 l , 83) This variant i s differentiated by the presence of Mahonia nervosa with high dominance in the layer over the moss carpet. It is situated between the Gaultheria shallon association and the counterpart of the same association, and i t is a drier variant which occupies submesic to subxeric habitats. Orloci ( 1 9 6 1 , 1964) recognized the Plagiothecium - Mahonia forest type as a warmer climatic variation of the moss type, and he also considered the Gaultheria - Mahonia forest type as a variation which developed on deeper soils than the orthic Gaultheria forest type. Though this variant (mahoniosum nervosae) is ecotopically close to the Gaultheria shallon association, i t i s distinguished from the association as follows: l ) absence of the striking development of Gaultheria shallon in the Bg layer, 2) higher dominancy of Mahonia nervosa, instead, and 3) the occurrence of Tsuga heterophylla which is rooting into the ground (growing not only on decaying wood or the substrata derived from decaying wood). Besides these, there are some minor differences In f l o r i s t i c structure. For example, Cornus canadensis has higher species significance in this variant than in the Gaultheria shallon association, the occurrences of Polystichum munitum and Smilacina stellata i s relatively common, and in the shrub layer Menziesia ferruginea is occasionally present but completely missing in the Gaultheria shallon association. i i ) hylocomiosum splendentis (Plot 0 3 , 0 6 , 08, 1 1 , l 6 , 1 9 , 2 8 . 31, 4 7 , 5 1 , 6 6 , 6 9 , 8 9 ) This variant i s differentiated from the former by lower coverage of Mahonia nervosa and higher dominance of Hylocomium splendens. instead. 89 Figure 21, Mahoniosum nervosae, one of the two variants of Hylocomio (splendentis) - Eurhynchio (oregani) -Mahonio (nervosae) - Pseudotsugo - Tsugetum hetero-phyllae, occurs on comparatively drier habitats than the other variant. High dominancy of Mahonia nervosa is a characteristic feature. (Plot 83, VIII 9 , 1969) Figure 22. Hylocomiosum splendentis, the other variant of Hylocomio (splendentis) - Eurhynchio (oregani) - Mahonio (nervosae) - Pseudotsugo - Tsugetum heterophyllae. High dominancy of bryophytes, including Hylocomium  splendens. Eurhynchium oreganum. and Rhyt i di adelphus loreus. is a characteristic feature. Since the associ-ation occurs on mesic habitats, i t is considered to be the closest to the zonal vegetation. (Plot 8 9 , VIII IT, 1969) 90 It f i t s hygrotopically to mesic habitats. In this variant, as well as the former one, Hylocomium splendens. Rhytidiadelphus loreus and Eurhynchium  oreganum are more important constituents than Plagiothecium undulatum which characterizes the orthic moss type in the drier subzone of the coastal western hemlock zone. Therefore, i t has a closer f l o r i s t i c and phytocoenological a f f i n i t y to the Pseudotsuga t a x i f o l i a - Tsuga heterophylla - Hylocomium  splendens - Eurhynchium oreganum association (Krajina and Spilsbury 1953) or the Pseudotsuga - Tsuga - Hylocomium association (McMinn 1957, I960) in the wetter subzone of the coastal Douglas-fir zone on eastern Vancouver Island, than to the orthic moss type described by Orloci and Lesko (l96l) in the drier subzone of the coastal western hemlock zone. Other aspects of the f l o r i s t i c composition also show more similarity to the moss type in the wetter subzone of the Coastal Douglas-fir zone. This would be, possibly, due to the unique influences of edaphic factors, that Is, soils are so rich in basic minerals that the strong leaching and removal of sesquioxides do not take place easily. The consequences of this is less development of the podzolic B horizon, even though the macroclimate is humid enough for development of Podzols. In fact, the data from the chemical analyses of the soils in this association show, in general, a higher velue of pH, total amount of cations, and base saturation than values obtained from the soils in the orthic Plagiothecium forest type analysed by Lesko (1961). The soils in this association including both variants are mostly Brunisols with strong reddish colored profiles, which are analogous to pararendzina soils (Kubiena 1953) developing on base-rich parent material. 91 U) VACCINIO (ALASKAENSIS) - ABIETO (AMABILIS) - TSUGION HETEROPHYLLAE Kojima & Krajina (U) Rhytidiadelpho (lorei) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) -Tsugetum heterophyllae = the Vaccinium alaskaense association (Plot 2 1 , 2 2 , 40, U l , 42, 5 7 , 5 8 , 5 9 , 6 l , 8 7 , 88) (Ref. Table 1 7 , 1 8 , 19) Characteristic combination of species: Constant dominant species: Abies amabilis Vaccinium alaskaense Constant species: Cornus canadensis Rubus pedatus Rhytidiopsis robusta Important companion species: Menziesia ferruginea Streptopus streptopoides Tsuga heterophylla  Rhyt i di adelphus loreus Clintonia uniflora  Plagiothecium undulatum Streptopus roseus Sorbus sitchensis In the study area, the occurrence of this association is confined to a particular l o c a l i t i e s (Elk River Valley, Heber River Valley, upper part of Wolf River Valley and Cervus Creek) where presumably the annual total precipitation exceeds 2800 mm. This is one of the representatives of the wetter subzone of the coastal western hemlock zone (Orloci 1 9 6 l , 1 9 6 4 ) . In the zone, since much of the precipitation occurs during the winter season, T a b l e ±J, RHYfIDIADT'LPIHl (LOW I) - llAGIOrilFCIO (IINI)ULATI) 92 (IT.DATI) - VACCINIO (ALASKAENSIS) - AHIETO (AHAOILIS) - TSIIGCTIJM HETEROPHYLLAE N o . o f P l o t P l o t N o . SI23 ( m 2 ) E l e v a t i o n (111) E x p o s u r e SIcoe g r a d i e n t ( d e g r e e ) S t r a t a c o v e r a g e : A B C Dh Ddw Dr Ground c o v e r a g e : humus m i n e r a l s o i l s r o c k d e c a y i n g s o o d b a s a l a r e a N u t t e r of s p e c i e s : 1 2 3 4 5 6 7 8 9 10 11 12 57 62 58 59 87 21 22 61 88 42 41 40 600 600 800 600 800 800 800 6 0 0 800 400 800 800 336 341 342 351 366 378 381 3 9 0 398 415 421 427 - - - - N56W N55W - - - - N20E ! l - - - - 12 2 - - - - 15 20 67 75 55 90 85 80 90 90 75 85 95 75 80 96 88 98 96 80 63 58 90 95 95 70 95 86 27 36 22 47 12 45 20 12 14 27 18 28 26 45 58 64 54 72 63 61 79 75 • 46 50 31 58 6 9 13 8 12 28 16 9 17 8 30 30 15 83 77 77 82 79 61 71 80 77 85 58 57 74 9 15 15 12 15 1 31 19 13 18 10 34 35 19 8 8 8 6 6 6 10 7 5 5 8 8 8 51 61 42 52 39 64 56 38 42 42 40 50 46 S p e c i QS S t r a t u m v ^ S p e c i e s S p e c i e s s i g n i f i c a n c e and s o c i a b i l i t y P r e s e n c e Dh D d » A b i e s a m a b i l i s Tsuga h e t e r o p h y l l a A b i e s a m a b i l i s Tsuga h e t e r o p h y l l a A b i e s a m a b i l i s Tsuga h e t e r o p h y l l a 6 . + 6 . 7 R h y t i d i a d e l p h u s l o r e u s 48 Hypnum c i r c i n a l e ' D i c r a n u m f u s c e s c e n s 49 S c a p a n i a b o l a n d e r i R h y t i d i o p s i s r o b u s t a 5 0 L o p h o z i a p o r p h y r o l e u c a 51 B l e p h a r o s t o m a t r i c h o p h y l l u m 52 C e p h a l o z i a l e u c a n t h a 53 C e p h a l o z i a media 54 L o p h o c o l e a h e t e r o p h y l l a H y l o c o m i u m s p l e n d e n s P l a g i o c h i l a a s p l e n i o i d e s Rhizomnium g l a b r e s c e n s 55 P t i l i d i u m p u l c h e r r i m u m 56 L e p i d o z i a r e p t a n s 57 L o p h o z i a i n c i s a 58 I s o p t e r y g i u m e l e g a n s 59 R i c c a r d i a p a l m a t a P l a g i o t h e c i u m u n d u l a t u m 60 Mnium s p i n u l o s u m 61 P l a g i o t h e c i u m d e n t i c u l a t u m 62 J u n g e r m a n n i a l a n c e o l a t a 63 S c a p a n i a umbrosa 64 C a l y p o g e i a f i s s a 65 J a m e s o n i e l l a autumnal i s 66 I s o t h e c i u m s t o l o n i f e r u m 67 H o o k e r i a l u c e n s 68 C a l y p o g e i a s u e c i c a 69 P e l t i g e r a membranacea 70 L o b a r i a o r e g a n a 71 A n t i t r i c h i a c u r t i p e n d u l a 72 S p h a e r o p h o r u s g l o b o s u s Hypnum c i r c i n a l e ' D i c r a n u m f u s c e s c e n s I s o t h e c i u m s t o l o n i f e r u m 73 Hypogymnia e n t e r o m o r p h a 74 P l a t i s m a t i a g l a u c a 75 A l e c t o r i a s a r m e n t o s a 76 C l a d o n i a o c h r o c h l o r a 77 L o b a r i a 1 i n i t a 78 C l a d o n i a c o n i o c r a e a S p h a e r o p h o r u s g l o b o s u s Hypnum c i r c i n a l e D i c r a n u m f u s c e s c e n s L o b a r i a o r e g a n a ( I s o t h e c i u m s t o l o n i f e r u m • S c a p a n i a b o l a n d e r i R h y t i d i a d e l p h u s l o r e u s A n t i t r i c h i a c u r t i p e n d u l a P l a t i s m a t i a g l a u c a Hypogymnia e n t e r o m o r p h a C l a d o n i a o c h r o c h l o r a P l a g i o t h e c i u m d e n t i c u l a t u m 79 R a d u l a b o l a n d e r i L o b a r i a 1 i n i t a R h y t i d i a d e l p h u s l o r e u s Hypnum c i r c i n a l e D i c r a n u m f u s c e s c e n s S c a p a n i a b o l a n d e r i H y l o c c m i u m s p l e n d e n s P l a g i o t h e c i u m d e n t i c u l a t u m S p a e r o p h o r u s g l o b o s u s I s o t h e c i u m s t o l o n i f e r u m P l a g i o c h i l a a s p l e n i o i d e s P t i l i d i u m p u l c h e r r i m u m I s o p t e r y g i u m e l e g a n s L o p h o c o l e a h e t e r o p h y l l a C e p h a l o z i a media C a p h a l o z i a l e u c a n t h a B l e p h a r o s t o m a t r i c h o p h y l l u m 80 B a z z a n i a d e n u d a t a 3 . 2 3 . 2 1.1 +.1 +.1 2 . 2 3 . 2 1.+ 6 . 6 6 . 6 5 . 5 5 . 5 4 . + 1 . + A b i e s a m a b i l i s 6 . 6 5 . 5 Tsuga h e t e r o p h y l l a 3 . + 2 . + 3 Taxus b r e v i f o l l a 1 . + „ 4 Thuja p l i c a t a 1 . + 1 . + 5 V a c c i n i u m a l a s k a e n s e 6 . 7 8 . 7 A b i e s a m a b i l i s 4 . 4 4 . 4 Tsuga h e t e r o p h y l l a - 3 . + 6 V a c c i n i u m p a r v i f o l i u m +.+ 7 M e n z i e s i a f e r r u g i n e a 5 . 5 _ 8 S o r b u s s i t c h e n s i s _ 1 . + 9 Rubus s p e c t a b i l i s 1 .+ _ 10 R o s a gyronocarpa 1 . + 1 . + 11 Mahonia n e r v o s a _ 12 Oplopanax h o r r i d u s +.+ 13 G a u l t h e r i a s h a l l o n _ _ 14 Rubus p a r v i f l o r u s T h u j a p l i c a t a +.+ -15 C o r n u s c a n a d e n s i s 5 . 2 4 . 2 16 C l i n t o n i a u n i f l o r a 3 . + 4 . + 17 Rubus p e d a t u s 3 . 1 1 . + 18 L i n n a e a b o r e a l i s 2 . 1 4 . 1 19 A c h l y s t r i p h y l l a 1 . + 4 . + 20 S t r e p t o p u s r o s e u s 2..+ 1 . + 21 C h i m a p h i l a m e n z i e s i i +.+ +.+ 22 O r y o p t e r i s a u s t r i a c a - _ 23 S t r e p t o p u s s t r e p t o p o i d e s +.+ 1 . + 24 T i a r e l l a t r i f o l i a t a - +.+ 25 P y r o l a s e c u n d a +.+ 26 C h i m a p h i l a umbel l a t a - +.+ 27 Goodyera o b l o n g i f o l i a +.+ 28 B l o c h n u m s p f l c a n t _ _ 29 V i o l a s e m p e r v i r e n s +.+ 30 L i s t e r a c o r d a t a _ 31 A t h y r i u m f i l i x - f e m i n a _ 32 G y n n o c a r p i u i d r y o p t e r i s - -33 M a l a h t h e m u n d i 1 a t a t u m +.+ -34 L a c t u c a mural i s - -35 C o r a l l o r h i z a m a c u l a t a - -37 ' ' I S a T f u T f n f i o r u m " " ' " 1 ^ " ' " _ 38 L i s t e r a c a u r i n a - -R h y t i d i a d e l p h u s l o r e u s 7 . 3 7 . 5 40 P l a g i o t h e c i u m u n d u l a t u m 4 . 2 4 . 2 41 R h y t i d i o p s i s r o b u s t a 1 . + 4 . 2 42 Hylocomium s p l e n d e n s - 1.1 43 R h i z o m n i u m g l a b r e s c e n s - -44 P l a g i o c h i l a a s p l e n i o i d e s - +.1. 45 D i c r a n u m f u s c e s c e n s -46 R h i z o m n i u m nudum - -47 P I a g i o m n i u m i n s i g n e - 1.1 6 . 7 4 . + 2 . + 5 . + 7 . 6 5 . 5 3 . + 4 . + 7 . 7 " 3 . + 5 . + 4 . 6 4 . + 6 . 6 3 . + 1 . + 1 . + 8 . 7 8 . 7 5 . 5 4 . 5 4 . 5 4 . 5 +.+ +.+ 1 . + -+.+ 1 . + +.+ 2 . + - +.+ 1 . + -- +.+ 5 . 2 6.1 4 . + 5 . + 2 . + 1 . + 2 . 1 4 . + 2 . 2 2 . + +.+ 1 . + +,+ +.+ 6 . 7 4 . + 6 . 6 4 . + 5 . + 5 . + 4 . + 7 . 6 4 . 5 4 . 5 4 . + 2.+ 1.+ 4 . 1 4 . 1 6 . 7 6 . 7 2 . + 6 . 6 6 . 6 5 . 6 5 . 6 3 . + 2 . 3 4 . 4 5 . 7 6 . 7 6 . 7 5 . + 6 . 7 2 . + 6 . 7 6 . 5 6 . 5 2 . 4 3 . 4 +.+ 5 . 6 7 . 7 5 . 5 5 . 6 4 . + 4 . + 6 . 6 6 . 6 6 . 5 2 . 4 5 . 7 4 . + 6 . 7 5 . + 5 . + 4 . + 3 . + 8 . 7 5 . 5 4 . 4 5 . + 4 . 7 5 . 6 5 . + 4 . + 3 . + 4 . 5 6 . 6 8 . 7 2 . + 1 . + 3 . + 2 . + 6 . 7 6 . 7 6 . 7 4 . 6 4 . + 4 . 6 4 . 5 4 . 5 8 . 6 4 . 4 4 . 5 1 . + 6 . 7 5 . 7 6 . 7 5 . 7 2 . + 4 . 5 3 . 5 5 . 5 8 . 6 5 . 5 6 . 5 2 . + 1 . + 1 . + 3 . 2 3 .1 4 . 1 4 . 1 2 . + 2 . + 1 . + 2 . 1 4 . + 4 . 2 - 1 . + - - 3 . + 3 .1 5 . 3 - +.+ 1 . + 3 . + 3 . + - -+.+ - +,+ 3 . + 1 . + -- 2 . + - -3 . + +.+ +.+ - -4 . 2 5 . 2 3 . + 1 . 2 7 . 4 5 . 2 4 . 2 3 . 2 1.1 2 . 1 1.1 1 . 2 1.1 3 . 3 3 . 2 3 . 1 1.+ 7 . 6 1.1 4 . 5 2 . 2 1 . + +.+ 4 . 2 1.1 1.1 +.1 +.1 1.1 7 . 6 +.+ 4 . 3 6 . 6 4 . 3 1.1 +.1 1.1 1.1 3 . 3 +.1 7 . 6 5 . 3 1 . 2 1.1 +.1 2.1 1 . 2 6 . 3 2 . 2 2 . 2 +.1 +.+ +.+ +.1 2 . 2 +.+ 1.1 1.1 7 . 6 5 . 3 4 . 3 3 . 2 5 . 3 +.1 2 . 2 1 . 2 +.1 - +.+ -8 . 4 8 . 7 7 ; 7 3 . 2 4 . 3 2 . 2 5 . 3 3 . 2 1 .1 3 . 2 3 . 2 2 . 2 - +.+ -+.+ _ - - +.1 2 . 2 4 . 2 . 3 . 2 3 . 2 4 . 2 2 . 2 2 . 1 2.1 2 . 1 +.1 +.1 1 .1 +.2 +.1 -+.+ - +.* +.+ +.+ +.+ +.+ +.+ +.+ +.+ +.+ +.+ +.+ +.+ -6 . 5 6 . 3 4 . 3 4 . 2 4 . 2 4 . 3 5 . 4 5 . 4 +.+ 2 . 1 5 . 5 3 . 2 2 . 1 3 . 2 +.1 +.2 1 . 2 2 . 2 +.1 +.1 +.+ 1 .1 1.1 4 . 2 2 . 2 2 . + 4 . 3 1.1 5 . 3 +.'+ 2 . + 5 . 3 +.+ 2 . + 3 . 2 1.1 1.1 1 . + 5 . 3 5 . 2 3 . + 1.1 +.+ 4 . 2 3 . 2 5 . 2 2 . + 3 . 2 +.+ 6 . 2 2 . + 1 . + +.+ 4 . 2 1.1 2 . + V V V V V IV V IV V V V IV IV I I I II II I I I V V V V V V V V V IV I I I I I I I t II II +.+ 2 . + 1 . + 2 . + +.+ 3 . + 2 . + 1 . + 3 . + +.+ +.+ +.+ V +.+ +.+ +.+ +.+ 4 . 2 +.+ +.+ 2 . 2 3 . 2 3 . 2 2 . 2 1.1 V V 1.1 2 . 2 +.+ 2.1 +.+ +.+ 3.1 2 . 2 +.+ +,+ 1 . + 1 .1 2 . 2 +.+ 1 . + 2 . + 5 . + +.+ +.+ 1 . + +.+ +.+ +.+ - V IV +.+ 1.1 +.+ 1.1 4 . 2 5 . 2 +.+ +.+ - - -- - - - 6 . 2 1 . + 5 . 2 - +.+ +.+ +.+ +.+ 111 II - -+.+ +,+ 3 . 2 2 . + - +.+ +.+ 1 . + II II I _ _ _ - - +.+ - +.+ - I +.+ - +,+ +.+ +.+ - -+.+ +.+ -I I I 2 . + 2.1 2.1 3 .1 4 . 2 8 . 2 8 . 2 2 . + 2 . + 4 . 2 - 4 . 2 V V 2.1 3 . 2 2 . 1 2 . 1 5 . 3 1.1 +.+ 2 . 1 4 . 2 3 . 2 1 . + 1.+ 3 . 1 2 . 1 1 .1 1 .1 2 . 2 2 . 2 +.+ 2 . 2 2 . 2 2 . 2 2 . 1 +.+ V IV +.+ _ +.+ „ _ 2 . + 2.1 2 . 1 +.+ +.+ +.+ +.+ 1 . + +.+ 1 . + 1 . + - - +.+ +.+ 1 . + +.+ - IV +.+ +.+ _ - +.+ +.+ +.+ - - -+.+ _ +.+ +.+ . - - +.+ - - III II II II -- - 1.1 3 . 2 +.+ +.+ 2 . 2 +.+ - +.+ +.+ +.+ +.+ A v e r a g e S p e c i e s S i g n i f i -c a n c e 5 . 4 5 . 3 4 . 8 3 . 7 3 . 9 2 . 2 5 . 2 3 . 0 0 . 7 0 . 2 7 . 3 4 . 8 3 . 3 1 . 2 0 . 8 0 . 2 0 . 5 0 . 3 0 . 1 0 . 1 0 . 1 0.1 2 . 1 2 . + V 3 . 8 3 . + 1 . + V 2 . 7 1.1 3 . 1 V 1 . 7 - ' - IV 1 . 8 +.+ - IV 1 . 2 3 . + IV 1 .1 - - IV + +.+ 1 . + 111 0 . 4 1 . + 1 . + I I I 0 . 2 +.+ +.+ 111 0 . 2 '- 1 . + I I I 0 . 1 - 1 . + I I I 0 . 1 +.+ - I I I + 5 . 2 5 . 4 II 0 . 9 - - II 0 . 1 +.+ - 11 + 0 . 3 0 . 1 6 . 9 3 . 7 2 . 8 1 . 4 0 . 2 0 . 1 + 0 . 3 0 . 2 3 . 8 2 . 3 1 . 9 0 . 9 0 . 2 0 . 6 0 . 1 0 . 1 + 0 . 2 0 . 1 0 . 1 - - +,+ +.+ I + - - +.+ - I + 6 . 3 5 . 3 5 . 3 4 . 3 V 4 . 3 „ 5 . 2 4 . 2 4 . 2 V 2 . 4 3 . + 3 . + 3 . + 2 . + V 1 . 2 +.+ +.+ +.+ 1 . + V 0 . 7 +.+ 1.1 1.1 +.+ V 0 . 2 1 . 0 0 . 2 0 . 2 0 . 1 1 . 2 1 . 2 1 . 0 0 . 9 0 . 9 0 . 1 0 . 9 0 . 3 0 . 2 3 . 4 2 . 2 1 . 6 0 . 5 0 . 4 0 . 4 0 . 1 SPORADIC S P E C I E S : Dh D d i T h u j a p l i c a t a 42 ( 5 . + ) E 114 115 B a c i d i a s p h a e r o i d e s C l a d o n i a m u l t i f o r m i s 22 40 (+.+) (+.+) T h u j a p l i c a t a 57 ( 4 . + ) Mnlum s p i n u l o s u m 22 (+.+) 81 C h a m a e c y p a r i s n o o t k a t e n s i s 42 ( 5 . + ) 116 P e l t i g e r a a p h t h o s a 22 (+.+) S o r b u s s i t c h e n s i s 57 ( 1 . + ) 117 P l a t i s m a t i a s t e n o p h y l l a 87 (+.+) 57 (+.+) R h y t i d i a d e l p h u s l o r e u s 41 (+.+) e2 A m e l a n c h i e r a l n i f o l i a S c a p a n i a b o l a n d e r i 21 (+.+) 83 R i b e s d i v a r i c a t u m 62 (+.+) 87 Taxus b r e v i f o l i a 62 ( 1 . + ) B l e p h a r o s t o m a t r i c h o p h y l l u m (+.+) 62 (+.+) 118 C l a d o n i a nemoxyna 59 (+.+) 64 A d e n o c a u l o n b i c o l o r 119 C l a d o n i a squamosa 41 (+.+) 85 A d i a n t u m pedatum 21 (+.+) 120 C l a o p o d i u m b o l a n d e r i 58 (+.+) 86 Bromus v u l g a r i s 21 (+.+) D i p l o p h y l l u m a l b i c a n s 41 (+.+) 87 C o p t i s a s p l e n i f o l i a 21 (+.+) 121 D o u i n i a o v a t a 22 (+.+) 88 D i s p o r u m h o o k e r i 62 (+.+) F r u l l a n i a n i s q u a l l e n s i s 87 (+.+) 89 G e o c a u l o n l i v i d u r a 59 (+.+) H e t e r o c l a d i u m p r o c u r r e n s 58 (+.+) 90 L y c o p o d i u m c l a v a t u m 40 (+.+) 122 H o m a l o t h e c i u m f u l g e s c e n s 58 (+.+) 91 P o l y s t i c h u m munitum 57 (+.+) .123 H o m a l o t h e c i u m n u t t a l l i i 58 22 40 58 40 (+.+) 92 S m i l a c i n a s t e l l a t a 21 (+.+) I s o p t e r y g i u m e l e g e n s (+.+) 93 T r i s e t u m cernuum 21 (+.+) 124 L o b a r i a p l u m o n a r i a (+.+) / \ 94 V e r a t r u m v i r i d e 57 (+.+) 125 N e c k e r a d o u g l a s i i (+.+) / \ 40 (+.+) P t i l i d i u m p u l c h e r r i m u m (+.+) C a l y p o g e i a s u e c i c a 95 D i c r a n u m h o w e l I i i 21 (+.+) E C 126 B a z z a n i a ambigua 42 (+.+) 96 D i p l o p h y l l u m a l b i c a n s 40 (+.+) 127 B a z z a n i a t r i c r e n a t a 42 ( + » 97 E u r h y n c h i u m oreganum 88 (+.+) 128 C l a d o n i a maci l e n t a 57 (+.+) I s o p t e r y g i u m e l e g a n s 40 (+.+) C l a d o n i a o c h r o c h l o r a 58 (+.+) P e l t i g e r a membranacea 21 (+.+) F r u l l a n i a n i s q u a l l e n s i s 40 (+.+) 98 R h y t i d i a d e l p h u s s q u a r r o s u s 40 (+.+) H e t e r o c l a d i u m p r o c u r r e n s 21 (+.+) S c a p a n i a b o l a n d e r i 41 (+.+) Hypogymnia e n t e r o m o r p h a 57 (+.+) 99 Sphagnum r u s s o » i i 42 (+.+) L e p i d o z i a r e p t a n s 42 (+.+) 21 ( + . - ) L o b a r i a 1 I n i t a 42 (+.+) A n t i t r i c h i a c u r t i p e n d u l a P l a g i o t h e c i u m u n d u l a t u m 22 ( 3 . 2 ) 100 B a r b i I o p h o z i a h a t c h e r i 62 (+.+) 101 C a l y p o g e i a m u e l l e r i a n a 62 (+.+) 102 C e p h a l o z i a c a t e n u a t a 40 (+.+) 103 C e p h a l o z i a d i v a r i c a t a 57 (+.+) 104 C e p h a i o z i a p l e n i p e s D i p l o p h y 1 1 um a l b i c a n s 88 (+.+) 41 (+,+) 105 flrepanocladus u n c i n a t u s 59 (+.+) 106 E u r h y n c h i u m p r a e l o n g u m v a r . . s t o k e s i l 62 (+.+) 107 F r u l 1 a n i a ni s q u a l l e n s i s 42 (+.+) 103 Gymnocolea i n f l a t a 62 (+.+) 109 110 H e t e r o c l a d i u m p r o c u r r e n s O r i h o c a u l i s k u n t z e a n u s . P e l t i g e r a membranacea 62 (+.+) 59 (+.+) 21 (+.+) 111 Pogonatum l a t e r a l e 22 (+.+) 112 Pogonatum macouni i 22 ( 1 . + ) 113 P o i y t r i c h u m formosum 21 ( 1 . + ) Table 1®* General environment in Rhytidiadelpho ( l o r e i ) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) -Tsugetum heterophyllae No, of p l o t : Plot No.: Elevation (m): Exposure Slope gradient (°): Climate (estimated): Biogeoclimatic u n i t : Light i n t e n s i t y (lu x ) : Land form: R e l i e f shape: Drainage: Hygrotope: Parent material: Thickness of humus (cm): Site index (m/100 years): Abies amabilis  Tsu.qa heterophylla 1 2 3 It 5 6 7 8 9 10 11 12 57 62 58 59 87 21 22 61 88 U2 Ul Uo 336 3>a 3U2 351 366 378 381 390 398 Ul5 1(21 U27 _ _ _ N56W N55W _ _ _ N20E N - - - - 12 2 - - - - 15 20 1272 8-10 1*3 ltl. 1483 1933 3356 old a l l u v i a l terrace .. f l a t a l l u v i a l deposits 8-12 10-20 10-15 CWHb 1556 1294 2836 h i l l s i d e .... terrace.... straight straight f l a t ... moderate mesic to subhygric g l a c i a l 10-15 5-8 15-20 1307 1U99 f l a t f l a t 236U h i l l s i d e f l a t 222li 2192 straight t i l l and outwash .... 20-25 15-20 15-20 30 U3 UO 37 30 Ul 27 33 U3 37 38 U3 35 37 38 33 30 33 8-10 U6 U7 10-15 UU U9 N O 94 Table 19. General characteristics of soils in Rhytidiadelpho (lorei) -Plagiothecio (undulati) - Rubo (pedati) - Vaccinioi (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae Factor unit of measurement minimum mean maximum pHs L-H horizon 3 . 6 4 . 2 5 . 7 A horizon 4 . 1 * . 7 5 . 5 B horizon 4 . 6 5 . 5 6 . 2 C horizon 4 . 9 5 . 6 6 . 5 Cation exchange capacityi humus m.eq./lOO g 3 9 . 4 110.8 169.0 mineral soils H 4 . 3 16.4 42.6 Total amount of» calcium eq./cub. m. 3 . 3 13.2 5 3 . 6 magnesium 1.2 3.1 5 . 0 sodium n 0.73 1.53 4 . 0 0 potassium M 0 . 5 0 0.96 2.51 organic matter kg/cub. m. 18.0 37.7 6 0 . 0 nitrogen g/cub. m. 401 662 1083 available phosphorus II 0.14 2.14 4 . 5 4 Base saturation! humus per cent 1 0 . 0 17.6 2 5 . 2 mineral soils 2 . 8 2 0 . 1 8 9 . 5 Carbon nitrogen ratiot humus 24 45 95 mineral soils 9 35 130 Field moisture % on volume basis 10.4 2 3 . 5 3 4 . 6 Field capacity n 14.9 24.7 34.1 Sand per cent 71.6 84.4 9 0 . 8 Silt M 7 . 0 13.9 2 5 . 5 Sand W 0 . 0 1.8 3 . 4 95 Figure 23. Rhytidiadelpho (lorei) - Plagiothecio (undulati) Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae occurs on mesic to subhygric habitats under the perhumid climate. Tree layer consists of Tsuga heterophylla. and Abies amabilis. Shrub layer well developed being dominated by Vaccinium alaskaense accompanied by Tsuga heterophylla and Abies amabilis. Humus is thick and extremely acid. Since this association occurs on mesic habitats, i t is considered to be close to the zonal vegetation under the perhumid climate. (Plot 5 9 , VII 22, 1969) Figure 2k. Rhytidiadelpho (lorei) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) - Abieto (amabilis) - Tsugetum heterophyllae. (Plot 5 7 , VII 1 8 , 1969) 96 i t would be conceivable that the wetter subzone would receive a considerably-higher amount of snow in winter, especially at high elevations, and snow would persist late in spring depending upon the local topographic conditions, e.g. well protected concave topography where snow drifts and accumulates. Thus, this association is found occasionally in relation to distribution of snow-pack on north-facing slopes or at the bottoms of valleys. In fact, in the study area, snow remained in the middle of June, 1969, at the bottom of Elk River Valley. Krajina (1969) recognized heavy snow accumulation with unfrozen ground is promotive to the establishment of Abies amabilis« particularly in areas where annual precipitation does not exceed 2800 mm. Kotah (1971) also recognized a strong correlation between ecological distribution of Abies  amabilis and snow. In the study area, this association occurs on gentle slopes of h i l l -sides or on terraces close to the bottom of valleys. The slope gradient ranges from 0 to 20 degrees with an average of k degrees. Parent material is mostly gla c i a l t i l l and outwash, and partly old a l l u v i a l deposits. The hygrotope of this association is rated as mesic to subhygric. The uppermost layer of the forest canopy is co-dominantly and ex-clusively composed of Abies amabilis and Tsuga heterophylla. As the shade tolerance of Abies amabilis is ranked the highest of a l l the tree species in British Columbia, and that of Tsuga heterophylla is also known to be very high (Krajina 1965, 1969), their seedlings and young trees are commonly found in a l l layers of the forests. This association, on the other hand, completely lacks the presence of Pseudotsuga menziesii. Crown closure is high, as an average of cover of the A layer is 80$. Light intensity under the forest canopy, therefore, is rather low, showing an average of 19^ +3 lux. In the A^ and Ao layers, in addition to the two previously mentioned species, Thuj a 97 plicata and Chamaecyparis nootkatensis may "be sporadically present. Both of these species require habitats rich in nutrients as well as water, and the latter species is better adapted to the subalpine habitats. The B^ layer i s composed mainly of the elements of the tree layer with sporadic occurrences of Taxus brevi f o l i a and Sorbus sitchensis. The B^ layer i s well developed, with Vaccinium alaskaense as the dominant which is followed by Abies amabilis and Tsuga heterophylla. Vaccinium parvifolium and Menziesia ferruginea are frequently present. Sorbus sitchensis, Rubus spectabilis, Rosa gymnocarpa, Mahonia nervosa and Oplopanax horridus are found occasionally in this layer. On the average, the coverage of the B layer i s 86%. The C layer is less de-veloped with an average u cover of 26%, probably due to the high coverage of the B layer above i t . Cornus canadensis is the dominant followed by Clintonia  uniflora and Rubus pedatus, both of them are characteristic species of the wetter subzone of the coastal western hemlock zone (Krajina 1959b,1965a). Achlys t r i p h y l l a . Chimaphila menziesii. Linnaea borealis and Streptopus roseus are frequent. Streptopus roseus is also a characteristic species of the wetter subzone. Ti a r e l l a t r i f o l i a t a . Chimaphila umbellata. Pyrola secunda, Goodyera oblongifolia. Dryopteris austriaca and Streptopus streptopoides occur occasionally. Though being very sporadic, the occurrences of Adiantum  pe datum., Adenocaulon bi color. Galium triflorum. Lactuca muralis. Maianthemum  dilatatum and Polystichum munitum are indicative of the richness in nutrients, in spite of high precipitation. The D layer on the humus is also well de-veloped, covering $8% of the forest floor. The dominant species is Rhyt i di adelphus loreus followed by Plagiothecium undulatum and Rhytidiopsis  robust a.-' A l l of these mosses are indicative of strong acidity of the humus. Rhytidiopsis robusta is a characteristic species of the wetter subzone. Rhizo- mnium glabrescens. Hylocomium splendens„ Plagiochila asplenioides 98 and Dicranum fuscescens occur frequently on the humus. Bryoflora on decaying wood in this association i s very ric h , amounting to forty-four species, out of which twenty-five species are liverworts. The diversity of the bryoflora is probably due to the damp conditions of the habitats, which are the results of perhumid climate and particular topographic situation. Rhytidiadelphus  loreus i s again the dominant on decaying wood. Hypnum circinale, Scapania  bolanderi. Dicranum fuscescens, Rhytidiopsis robusta, Lophozia porphyroleuca, Blepharostoma trichophyllum, Cephalozia leucantha and C. media occur con-stantly. Lophocolea heterophylla. Hylocomium splendens, Plagiochila aspleni- oides. Rhizomnium glabrescens. Ptilidium pulcherrimum. Lepidozia reptans, Lophozia incisa and Isopterygium elegans are found occasionally. The epi-phytic layer i s relatively well developed being dominated by Lobaria oregana which occurs mainly on branches of the tree canopy. On tree trunks, Anti- t r i c h i a curtipendula. Sphaerophorus globosus. Hypnum circinale and Dicranum  fuscescens are found constantly. Peltigera aphthosa occasionally grows on the bark of Abies amabilis. Lobaria l i n i t a is found sometimes occurring on tree trunks in this association. Isothecium stoloniferum occurs frequently in this association hanging on branches and bark of conifers, indicating the high atomospheric humidity of the sites. E layer is dominated by Rhytidiadelphus loreus which is essentially a humicolous bryophyte. Dicranum fuscescens. Hypnum circinale and Scapania bolanderi are found con-stantly in this layer. Productivity of this association is medium. The site index of Tsuga heterophylla i s ko m/100 years; that of Abies amabilis is 37 m/100 years on the average. In this association, s o i l texture is coarse. Soils are mostly loamy sand or sand, and coarseness tends to increase with depth. The general characteristics of soils are shown in Table 19. Generally the pH value of 99 Figure 2 5 . Fruiting Vaccinium alaskaense. The species indicates perhumid climate with annual to t a l precipitation more than 2500 mm. It i s , therefore, one of the character-i s t i c species of the wetter subzone of the coastal western hemlock zone. (Plot 2 2 , IX kt 1969) Figure 2 6 . Fruiting Streptopus streptopoides occurring on a moss carpet. The species is one of the characteristic species of Rhytidiadelpho (lorei) - Plagiothecio (undulati) - Rubo (pedati) - Vaccinio (alaskaensis) -Abieto (amabilis) - Tsugetum heterophyllae, indicating strongly acid raw humus conditions. Major bryophyte in the photograph is Rhyt i di adelphus loreus. (Elk River Valley, IX k\ 1969) 100 is very low with an average of h,2t which is the lowest among the associ-ations. Humus is rather thick (5-25 cm) and somewhat compacted. The pH value increases with depth up to 5.6 which is an average of the C horizon. Generally, total amount of cation exchange capacity, extractable cations (calcium, magnesium, sodium and potassium), nitrogen, carbon, and available phosphorus decrease with depth. Base saturation of humus is the lowest among the associations, probably due to the strong percolation of rain water and relatively cool climatic condition of the habitats. Base saturation of the mineral soils is also relatively low. Soils in this association are mostly Brunisols (Dystric Brunisols). In spite of the high amount of precipitation, Podzols are rare. Only one case was found to be Podzol out of a l l soils examined. Again this i s probably due to the strong influence of base-rich parent material over the influence of climate. Orloci (l96l) designated Abieteto - Tsugetum heterophyllae as a mesic zonal forest type in the wetter subzone of the coastal western hemlock zone. It comprises two variants, i.e. clintoniosum uniflorae and acerosum c i r c i n a t i . They are differentiated from each other f l o r i s t i c a l l y by the presence or absence of Acer circinatum. Ecotopically, the former is well adapted to long snow duration and short vegetative season, whereas the latter is well adapted to warmer climate with less snow. This association is compa-rable to the association of Orloci's Abieteto - Tsugetum heterophyllae, es-pecially to the variation clintoniosum, since i t completely lacks Acer  circinatum. There are, however, some differences between the two in the following respects: l) the proportion of Abies amabilis to Tsuga hetero- phylla in the A layer is higher in this association than in the Orloci's, 2) Vaccinium ovalifolium which is constantly occurring in Orloci's is almost missing in th i s , 3) in the herb layer, Blechnum spicant which is the most 101 frequent and important constituents in Orloci's association is rather rare (presence class II) in this association. These facts would be explained by the richness in base status of the habitats in spite of the high precipitation. Actually, the amount of calcium as well as magnesium in the soils and the base saturation are much higher in this association than in Orloci's associ-ation which was analysed by Lesko ( 1 9 6 1 ) . The pH values are generally higher in this association, too. This association has a close a f f i n i t y to Streptopo (rosei) -Abietetum amabilis, especially to the variation tsugosum heterophyllae, described by Brooke (1966,Brooke et JLL . 1970) as one of the associations from the Forested Subzone of the subalpine Mountain Hemlock Zone in British Columbia. This association, however, is distinguished from Brooke's by the absence of Tsuga mertensiana, Vaccinium membranaceum and Vaccinium ovalifolium, a l l of which are essentially subalpine elements. Franklin and Dyrness ( 1 9 6 9 ) recognized the "Abies amabilis" zone, which was analogous to the wetter subzone of the coastal western hemlock zone, in between the temperate mesophytic Tsuga heterophylla zone of the lowland and subalpine Tsuga mertensiana zone on the western slopes of the Cascade Range in Oregon and Washington States, designating Abies amabilis -Vaccinium alaskaense association as the zonal climax communities which is typified by the occurrences of the following species: Vaccinium alaskaense. Vaccinium ovalifolium, Cornus canadensis. Clinton!a uniflora, Linnaea borealis and Rhytidiopsis robusta. 102 3. THUJETALIA PLICATA Krajina in Brooke 1965,Krajina 1969 .Brooke et al.1970 Thujetalia plicatae is the order which represents edaphic climax communities developing on hygric to subhydric habitats where seepage or stream water is present. In the present study area, therefore, i t is found on the lower slopes of hillsides and on a l l u v i a l flood plains or stream-edges at the bottom of valleys. Ecotopically, these habitats are extremely rich in mineral nutrients due to continuous supply of the nutrients by seepage water. On such habitats, Thuja plicata would be the f i n a l tree species forming edaphic climax, since the habitats are already over-maxima for the requirements of Tsuga heterophylla regarding the nutritional status, while Pseudotsuga menziesii becomes shade intolerant on these moist habitats. Abies  grandis may be able to compete with Thuja plicata as far as edaphic condi-tions are concerned, but the species is essentially well adapted to the drier climate. The following are the characteristic combination of species: Acer macrophyllum Disporum hookeri Cornus n u t t a l l i i Gymnocarpium dryopteris Thuja plicata Luzula parviflora Acer glabrum Montia s i b i r i c a Ribes divaricatum Polystichum munitum Rubus spectabilis Smilacina stellata Symphoricarpus albus Streptopus amplexifolius Achlys triphylla Tiarella t r i f o l i a t a Actaea rubra Trautvetteria carolinensis Adenocaulon bicolor Plagiomnium insigne Asarum caudatum 103 In the present study area, three alliances and three associations with three variants were recognized. 5) MAHONIO (NERVOSAE) - POLYSTICHION MUNITI Kojima & Krajina (5) Eurhynchio (oregani) - Tiarello (trifoliatae) - Polysticho (muniti) - Achlydo (triphyllae) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae = the Achlys - Polystichum association (Plot 02, 04, 13, 14, 15, 17, 20, 23, 25, 32, 39, 46, 50, 52, 1. , 73, 74, 75, 77, 82, 84, 90, 91, 92) (Ref. Table 20, 21a, 21b, 21c, 22) Characteristic combination of species: Constant dominant species: Pseudotsuga menziesii Achlys t r i p h y l l a Constant species: Vaccinium parvifolium Ti a r e l l a t r i f o l i a t a Eurhynchium oreganum Important companion species: T i a r e l l a laciniata Festuca subuliflora Smilacina stellata Tsuga heterophylla Mahonia nervosa Polystichum munitum Lactuca muralis  Disporum hookeri  Streptopus amplexifolius This association covers extensive areas and develops on moderate slopes of hillsi d e s or close to the bottom of valleys. Occasionally, i t may Table 20. EURHYNCHIO (OREGANI) - TIASELLO (TRIFOLIATAE) . POLYSTICHO CI1IIITI) - ACHLYDO (TRIPHYLLAE) - PSEU30TSIM) . TSUGO C r i t l £ R C ? K f L U E ] - M U t T i * PLICATAE 104 ACklYDOSUa TRIPHYLLAE CYMIKtRPIOSUS DRY0P1ERI0IS POLYSTICH03U! ! u : i l ' Ko. of plot 1 2 3 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 P l o t llo. 71 90 91 92 13 25 52 02 OA 15 32 23 1A 46 73 74 75 84 50 73 77 82 20 17 39 Size { . ) SCO too BOO 800 800 800 800 600 800 500 600 800 ' 800 600 600 800 800 600 600 600 BOO £03 300 ECO SCO Elevation (•) 229 23B 270 270 351 AOS 238 320 320 330 335 402 351 390 223 229 229 23S 24A 250 269 275 105 310 3?t Exposure HI6E M i l - - SIDE sta S66I - H201 S S30E seoE S10E 11451 - - - 5 SEOS SS5>- I S4£i S4>: S7!I S20E Slope gradient (degree) 8 3 - - 5 20 8 - 3 3 5 20 5 33 - - - 30 15 10 28 1! 10 20 20 Avenge S t r a t a coverage (J): A B 95 55 60 75 93 68 95 92 90 65 85 72 9A 11 88 60 92 75 78 60 63 SO 70 :4 76 81 B 25 B5 60 A3 12 5 31 55 33 A3 25 13 12 20 25 6 25 28 25 A3 30 23 15 20 29 C 57 70 80 80 57 65 60 55 60 86 33 70 81 84 60 54 80 67 64 68 55 70 SO AS 96 69 Dh 35 77 24 8 IB 13 16 33 12 1A 5 20 13 10 22 23 10 49 39 26 32 40 10 36 68 25 Dde 5 6 25 It 8 8 II 12 15 3 A 10 6 2 14 6 8 8 26 12 31 23 5 14 10 11 Or - - - - - 6 - - - - - 3 - 7 3 4 28 32 4 3 Ground coverage ( a ) : huous 59 Bl 73 67 68 76 69 65 82 69 68 2 75 59 78 79 77 7B 55 76 53 63 47 40 74 68 slnera) t o l l s - - - - 1 - - - 2 - 2 1 rock . 11 - - - . 5 - 30 5 6 36 35 6 5 decaying eood 33 9 30 17 23 13 12 20 23 6 8 16 12 2 22 11 11 14 36 16 34 23 16 15 12 17 basal area S 10 10 10 9 8 12 11 10 12 11 9 12 9 10 10 12 6 9 6 £ 8 9 10 E 10 Nnnhar of species 51 45 59 52 45 51 51 <5 5t AB 50 59 49 4S 40 44 46 52 SO 45 54 54 43 47 44 50 Species s i g n i f i c a n c e and s o c i a b i l i t y species S i g n i f i -cance 100 101 Pseudotsuga e e n z l e s l l Ihuja p i I c a t a Tsuga heterophylla Pseudotsuga menziesii Tsuga heterophylla Thuja p l i c a t a Tsuga heterophylla thuja p l t c a t a l e e r aacrophyllua Pseudotsuga c e n z i e s l l Cornus n u t t a l l i i Abies grandis Tsuga heteropiiylla Acer nacrophyllun Tsuga heterophylla Vacctnlua p a r v l f o l l u a Mahonia nervosa Rosa gyanocarpa Oplopanai horridus Vaccinluo alaskaense B e m l e s l a ferruqtnea Abies grandis Cornus nuttal111 Rubus s p e c t a b l l l s Rubus urslnus - Aselanchter a l n l f o l l a Abies amabilis Rubus parvi ft or us Acer glabruo Thuja p l i c a t a Rlbes dlvartcatua Symphoricarpus at bus Achlys t r t p h y l l a Potystlchuo munitum K a r e l i a t r i f o i l a t a Llnnaea boreal Is Dlsporua hooter, Athyrlua f l l i x - f e m l n m V i o l a seopervlrons Gal 1ua t r l f l o r u a T r l e n t a l i s l a t l f o l l a Lactuca a u r a l l s T i a r e l l a l a c l n l a t a Goodyera o b l o n g l f o l l a Cyeinocarplun dryopterla S o i l actna steI l a t a Cornus canadensis Adenocaulon b l c o t o r AdiantuB pedatua Streptopus amplextfollus Dryopterts austriaca Chlnaphtla n e n z l e s l l festuca s u b u l l f l o r a C l i n t o n i a u n i f l o r a V i o l a g l a b e l l a ChlejfihUa unbellata Pyrola secunda Bonotropa u n l f l o r a Pyrola p l c t a T r a u t v e t t e r U c a r o l l n e n s l s Hontla s l b l r l c a L i s t e r a caurlna Blechnun splcant Asarum caudatua Pterldtun aqul 11 nua C o r a l l o r h i z a oaculata l u z u l a parvi f l o r a Eel lea subulata Eurhynchlua oreganua Hylocoaluo splendens Rhytidiadelphus loreus Ptaglonnlus inslgna Rhytidiadelphus t r i q u e t r u s Knlua splnulosua R h y t i d i o p s i s robusta L»uco)ep1s oenztestl Plaglothecluo undulati™ Hypnua c i r c i n a l e Scapania bolanderi Eurhynchlua oreganua Otcranura fuscescens Hylocomium splendens Rhytidiadelphus loreus Isothecium s t o l o n l f e r u a P l a g i o c h i l a asplenioides Rhlzcantua glabrescens l e p i d o z i a reptans Cephalozia leucantha Cephalozia media Rhytidiadelphus triquetrus P t l l l d i u a pulcherrleua Scapania uabrosa Rhytidiopsis robusta Plagiothecium undulatua Pleurozlua schreberi Heckera douglasii Heterocladium procurrens Calypogeia f l s s a Calypogeia trlchooanls P o r e l l a n a v i c u l a r ! ; Hylocool us splendens Isotheciua s t o l o n l f e r u a Rhytidiadelphus loreus Plagloanlua inslgne Heterocladium procurrens Claopodlua bolanderi Heterocladium macounii Knluo splnulosua P l a g i o c h i l a asplenioides Rhacooltrium heterostichua Dlcranurc h o i e l l l i Rfilzonnlua glabrescens H>pnua e l r c l n j l e Plj . j lotheetuo p i l i f e r u m R h y t i d i o p s i s robusta t s o p t e n g l u a elegans P l a ; l o t r e c l u a u ^ u l a t u a P e l t i g e r a aphthosa Isotheciua stoloniferum 5phaeroptionjs globosus A l e c t o r i a sariantosa Lobarla oregana F l a t l i e a t l a glauca Hypogycnla enterosorpha Dlcranua fuscescens Hypnua c i r c i n a l e Neckera douglasii S c a r i n l a bolanderi P l a t i t u t t a stenophylla F r J I a n l a n i s q u a l l e n s i s P o r e l l a n a v i c u l a r s A n t i t r i c h i a curtipendula Clacradlua bolanderi lsDtr .ec.ua s t o l o n l f e r u a Hypnum c i r c i n a l e Dicranum fuscescens ',pl.jeruiihurui rjlohot.ua P l i t l m t l j gUuca Neckerj douglasii Frul Idiila n l s q u j l l e n s l s Hypogymnia enteroaorpha Lobari a areqana P o r e l l a n a v l c u l a r l s C1aopod.ua bolanderi Plagioanlua venustua P o r e l l a cordaeana A n t i t r i c h i a curtipendula P t l l l d i u a pulcherrtrnum Hoaalothecium fulgescens Hypnua c i r c i n a l e Dlcranua fuscescens Scapania bolanderi Isotheciua stoloniferum Eurhynchlua oreganum Rhytidiadelphus loreus Hylocoalua splundons Sphaerophorus globosus P l a g i o c h i l a j^plenloldes Claopodlu* bolanderi Neckera douglasl I P l a t l s a a t l a glauca Cladonia ochrochlora Heterocladlua procurrens Pore I la n a v l c u l a r l s Cephalozia oedla Cephalozia leucantha P t l l l d i u a pulcherrlnua Plaglotheclun dentlculatua 7.7 5.7 6.7 7.7 3.5 6.7 7.7 6.7 6.7 6.7 6.7 7.7 7.7 6.7 7.7 7.7 6.7 6.+ 6.7 5.7 6.6 6.7 6.7 7.7 3 . * 7.6 6.6 2.4 4.+ 1 . * 2.2 6.6 3.6 3.5 4 . * 2.5 - 5.6 6.6 2.* 5 . * 5.5 3 . * 6.6 2 . . 6.7 4.5 5.6 V 1 . * - 1 . * 3.+ 1 1.* 1.3 6.5 5.6 6.5 3.4 5.6 5.3 6.5 6.6 6.5 4.4 4.4 4.5 3.S 3.4 ! . • 2.+ 6.4 1 . * 7.5 ! . • 1 . * 4 . * 4.6 V *.* 3.+ 4.5 5.5 2.+ • . • 4 .3 3.4 3.5 3.4 4.4 3.3 +.+ 3 . * 2 . - 1.+ 2 . * • .+ 1.+ 2 . * \.+ 3.+ 1.3 1.3 1/ 2.3 4.3 4.4 2 . * 3.3 4.4 +.3 . . 2 1.2 1.3 1 . * 1.+ - 4.3 4.5 4.5 2.3 5.3 * . 3 • . 3 1.3 V 1 . * _ +.+ 1.3 1 . * _ 2.4 1.4 2.* - U 1.+ 2 . * 1.+ 2.3 1 . * * • * *•* IV _ *.+ +.+ _ _ 2.4 1.* 1.3 3.4 1.+ - 1 . * +.• 3.3 - - - III 4.+ A.5 3.5 1.+ 2.3 3.4 • . 3 3.2 - - - - - - - - - - - II 2 . * 1.+ 1.+ • . 3 - - - - - - - - - - - *-* 11 *.+ - - - 3 . * - • . 3 - - - - - - 11 1.+ - - - * • * - II - - - - - - +.3 • . 2 1 . * II '' +.+ - - - - - - - - - - - - - - +.+ II - - - -8.7 7.5 ?. a 6.7 7.3 7.5 8.6 6.7 6..7 6.7 6.7 5.3 8.7 5.4 6.7 6.6 a.a 5.3 6.5 5.4 1 . * _ 2.2 . 1.4 3 . * 1 . * 1.4 1.4 1.3 2.1 3.3 1.3 7.5 6.5 6.5 4.5 7.6 6.6 7.6 2.2 4.3 5.2 3.2 5 . 2 •.+ 3.2 3.2 4.2 2.1 2.2 4.2 3.2 2.1 1 . * 3.2 1 . * 1 . * l . f +.+ 6.2 2.3 2.1 1.2 - 3.1 1.1 1.2 - 1 . * • J 1.+ *.• - 2.1 1 . * • *.+ 2.+ 1.+ 1.3 • . • • . * 4.3 4.2 - 1.3 2 . * 1.+ *.* 1 . * •.* 2.+ 1.+ +.+ • , • 1.3 1.+ 1 . * 1.3 - - - 2.3 1 . * 1 . * 2 . * 2.1 1.1 1.+ 2.1 2.1 1.1 1.1 - 1.1 - - *.• - -+.• - • . 2 • . 2 2 . * - +.2 - 1 . * 1 . * *•* 5.3 5.3 8.6 6.6 6.A £.6 t . 2 5.3 3.2 3.3 2.1 2.2 5.6 • . 2 1.1 6.7 3.2 1.. 2.2 » . 2 1.2 . . 1 6.6 3 . -2.2 1.1 6.2 3.1 8 .8 5,4 3.3 1.2 3.2 6.3 4.3 4.4 4.3 +.2 2.2 6.3 2.1 5.3 4.3 4.3 6.3 5.S 5 . 2 5.2 5.3 6.6 6 . 5 6.6 2.1 +.2 2.3 3.1 3.4 1.3 • . 2 - 3.2 5.4 1 . * 5.3 5.4 t . 2 4.2 3.2 4.3 4.5 4.3 +.1 4.4 3.3 4.5 _ 5.4 • . 2 - 4.4 1.2 2.2 4.4 4.4 -.1 - 2 . » - - 1.3 2.1 4.3 _ •.1 2.2 2.2 3.1 3.2 2.3 3.2 - - - 1.+ I . - 4.1 4.3 1.2 1.2 4 . 2 •.1 _ 3.2 - - - - - 2.2 - • . 2 - *.+ •.1 3.3 I .I - - - -- +.+ 1.+ 1 . * - - - - - - - - - •.1 _ +.1 +.f 5.5 1.1 - - - 3.2 - - - - - - - - - - - • 4.2 - - •.1 2.2 3.2 1.1 2.1 3.2 4.2 2.3 3.3 2.2 3.2 3.2 3.3 2.3 +.1 2.2 4.2 3.t 3.3 +.2 2.1 3.2 3.2 1.3 3.2 •,1 1.2 +.+ +.1 *.+ 3.2 1.1 •.1 1.1 • . t 3.2 2.2 1.1 1.1 1 . * •.1 2.1 1.1 . 2.2 1.2 •.1 +.1 •.• 2.2 - - +.1 +.1 •.1 2.2 • . 2 3.2 * .1 3.2 • . 2 •.1 1.2 •.1 •.1 •.1 - - - -+.+ •.1 - - •.1 - -- *.* 3.3 - - - - * .1 - - *.+ - -- - - - - -_ - - - - - • +.1 - 1.1 - - - *.1 - - -- +.+ - - -- - - - -3.2 3.2 1.2 1.2 2.1 *.1 1 . » 2.2 2.2 2.1 1.1 5.t t.3 3.2 2.1 . . 1 2.2 +.1 2.2 2.1 2.2 2.2 1.1 1.2 1.1 3.2 2.2 2.1 3.2 2.2 2.1 3.2 5.3 4.2 2.1 +.+ +.+ 2.2 i.i - 3.5 5.2 4.2 - 2.1 2.1 2.1 2.1 3.2 3.2 >.+ 2 . * +.* 2.+ 1 . * 1 . * 2 . 2 3 . 2 2.2 1.1 3.2 * . * * . * * . * 1 . * * . * * . * 1 . . 2.1 1.1 • . • 1.1 1.+ _ 2.1 2.2 +.+ 1 . * 1 . * *.+ +.* +.» 1.1 1 . * 2.+ *.+ 1 . * *,* 1.1 1 . -+.+ . 1.1 1.1 - - - 1.+ 2 . * 2.1 1.+ +.+ +.* 1.1 - 1 . - 1 . * 1 . * 1.* *.* +.+ 3.1 +.+" +.+ *,+ 1.2 2.1 1.1 - 1.1 +.+ +.+ +.+ +.* * . • *.+ ».+ • . • +.+ 2.1 - _ +.• +.«• 1.1 1.1 - * .• - +.+ •*.• • . • *.+ +.* *.+ _ 3.2 +.* +.•• +.+ +.» - *.+ +.+ - - 2.2 1 . * _ +.+ +.*• - - 2.1 - +.+ - 1.+ - - - - 3.1 2.2 ; 1.1 - • 1.1 2.1 2.1 1.1 1.1 3.2 5 . 3 _ 3.2 +.+ 1.1 4.3 2.2 +.• 2.2 2.2 3.2 2.2 1 . * 3.2 2 . * 3.2 2.1 2.2 2.2 V *.* 2.+ 4 . * 3.2 1 . * 2.1 2.2 2.2 2.2 1.1 • . • 2.1 1 . * 2.1 +.* 2.1 2.1 2.1 2.1 2.1 1.1 3.2 2.1 V 4.1 3.2 1 . * +.+ 2.2 2.2 2.2 1.1 *.• 1 . * 2 . * +.+ +.* 1 . * 1 . * 1 . * 1 . * 2 . * • . • 1 . * 1 . * V •.* 3 . * +.+ 2 . * 1 . * 1.1 2.1 1.1 2.1 2 . * - *.* 1 . * 1 . * * - * «.* *.* V 4.2 2.1 •.+ •.+ +.• - 1 . * - - - - - - - *.* *.* IV 1 . * 2 . * _ +.* •.+ 1 . * +.+ - - - 1 . * *.* - - - IV 4.2 _ - - - 4.2 2.1 1 . ! 4.2 - 3.2 - - - II II _ - - - - - - - - - *.* - - - - - II 6.0 0 . 3 1 0.6 5 . * 6.7 t.. _ 6.6 5.7 6.7 _ 5.7 t .7 3 . » 4 . * 5.7 4 . . 4 . * 3 . . 5.6 5.5 4 . . 2 . . IV 3.2 4 . » 5.7 5 . » t . » 5.7 5.7 5.7 6.7 6.7 5.6 - - - 6 . . 6 . » - 2 . . 3 . » 5 . . 6.7 IV 3.1 - 5 . . 5 . * - ! .* - 5.6 6.7 5.7 t .6 3 . . S.7 - 6 . » 6 . » 4 . . - - 5 . . - - - - III 2.5 5 . * 4 . . 6.7 3 . » 5.6 5 . « 5 . . 5.6 . 6.7 4 . * 4.6 6.6 4 . . 5 . . 4 . . 4 . . A . . - 2 . . 6.6 6.7 6.7 V 4.0 5.6 t . » t .6 t .6 5.7 3 . . 4 . * 4 . 6 4 . » 2 . » - - 5 . - - 2 . . - - - - III 2.0 6.6 II II 0.6 0.5 0.4 0.2 3.7 0.3 3.8 2.2 1.7 0.6 0.5 O.S 0.2 6.0 3.E 2.4 1.0 0.3 0.7 0.5 0.2 0.2 0.2 0.1 0.6 0.3 0.3 0.2 0.1 0.1 0.1 0.2 0.2 4.2 2.5 1.6 1.2 0.7 0.1 0.4 4.3 1.3 4.3 3.4 V 2.5 2.2 3.3 3.3 3.4 V 2.4 3.2 1.2 3.2 +.1 V 1.1 2.1 •.1 1.2 1.2 V 1.0 3.2 . 2.2 *.+ V 0.6 1.2 +.* *.1 V 0.6 1 . * * . t 2.2 - IV 0.3 * .1 1.2 . IV 0.2 •.1 IV 0.2 1.2 III 0.1 - - t i l • ... U l * 3.1 - - - II 0.2 - II - - - II * 1.1 1.1 5.4 3.2 . . . V 1.9 1.1 +.• 2.1 3.3 1.1 V 1.5 +.+ 2.2 1.2 . , * 1.4 1.1 1.1 2.1 2.2 1.1 V 1.4 *.* 1.1 1.1 V 0.£ f . * 2.1 *.+ V 0.5 *.* - -.« IV 0.3 •.• - 1.1 IV 0.1 1.1 - IV 0.1 0.7 0.6 0.3 0.2 0.2 0.2 0.4 0.1 0.1 0.1 0.1 0 . 1 1. B 1.6 1.0 0.6 0.3 0.2 0.7 0.2 0.1 0.1 0.1 2.1 3.2 3 . 2 5 . 2 3.2 2.2 3.2 3.2 5 , 3 2.2 3.2 2.2 2.2 2.2 4.2 3.1 2 . * 2.1 2.1 2.1 3.1 2 .2 2.2 3.2 V 2.6 1.+ 2.2 2.2 4.2 2.2 1 . * 2.2 2.2 3.2 2.2 1.1 2.2 2.2 2 . * +.+ 2 . * 1 . * 2.+ 2 . * 2.+ 1 . * 1 . * *.* ... V 1.6 1.1 1.1 6.2 5.2 +.+ . 3.2 3.2 1.2 1.1 1.1 2.2 2.1 4.2 3.1 •.+ 2 . » 2.1 2.1 2.1 3.1 2 .2 2.2 3.2 V 1.4 +.+ •.• 2.2 +.• - 4.2 ».+ •.<• - 1.1 - - - 2.2 - *.* 3.2 - 2.1 1.1 2.1 IV 0.7 . . 2.1 _ - 3.2 *.+ - 1.+ - 2.1 2 . * t . * 2 . - 1.+ 1 . * 1 . * *.+ 1 . * IV 0.6 _ 1.+ 4 . 2 3.2 2.1 2.2 3.2 - - - - - - 2.1 - - - 1 . * - - 2 . * I t ! u.7 - I l l 0 .2 _ _ 4.+ - - - - 1 . * 1.1 • - - - . . . - - - 11 0.1 1.1 _ _ - - - - - - - - - - - - II 0.1 _ _ .1.1 - - 1.1 - - - - - •.• - - - - - - - II 0.1 - - 1.1 1 0.2 SPORADIC SPECIE5 * 2 Abies a e a b l l l s 02 ( A . » ) , OA (3.7) Abies grandis 50 ( 6 . 7 ) , 77 ( t . » ) Acer Bacrophyllua 52 ( 5 . . ) Abies a o a b l l l s 46 ( 3 . » ) , 90 ( 3 . » ) Abies a n a b l l i s 23 ( 3 . . ) Abies grandis 50 ( 2 . * ) Acer c l r c i n a t u a 32 ( 2 . » ) ' Cornus n u t t a l l i i 77 ( 2 . . ) , 82 ( 5 . . ) 105 Pinus e o n t k o l a 71 ( 1 . - ) Pseudotsuga m o i l e s l l 71 ( 1 . . ) Acer aacrophyllua 32 ( 1 . . ) , 77 ( 1 . . ) 106 Gaultheria s h a l l o n 04 ( . . . ) , 92 ( . . . ) Pious o o n t l c o l a 84 ( • . . ) Pseudotsuga n e n z l e s l l 52 (•.-.) 107 Sanbucus pubens 77 ( • . . ) 108 Vlburnun edule 04 (-..•) 109 *Actaea rubra 15 ( . . . ) , 32 ( . . . ) 110 A l l o t r o p a v l r g a t a 90 (• .•) 111 Aneaane l y a l l l l 52 ( » . • ) 112 Arenarla eacrophylla 82 ( • . . ) 113 firoaus v u l g a r i s 15 ( . . . ) , 32 (• .•) 114 Olcentra lormosa 32 ( » . - ) 115 Hypopttys oonotropa 17 ( » . • ) 116 L i s t e r a cordata 04 ( . . . ) , 25 ( . . . ) 117 Lycopodlun clavatua 04 !->.») 118 llalanthenua d l l a t a t u a 02 ( » . . ) , Ot ( . . • ) 119 Oseorhlza c h l l e n s l s 71 ( . . . ) 120 Pyrola vlrens 91 ( . . . ) , 92 ( . . » ) 121 Rubus n i v a l i s 73 (• .•) 122 Rubus pedatus 13 (..<•), 23 ( . . . ) 123 S t e l l a r t a c r l s p a 32 ( . . . ) 124 Streptopus rosetis 04 ( . . . ) 125 Streptopus streptopoldes 17 ( . . . ) 126 T r l t e t u a cernuua 1t ( . . . ) , 52 ( . . . ) 127 Atrlchua undulatua 91 ( . . . ) 6lepharostoaa trfchophyltua OA ( . . . ) 128 Brachytheclua albicans 91 ( . . . ) 129 Drachytheclua larprochryseua 84 (1.1) Dlcranua fuscescens 02 ( . . . ) 130 D l t r i c h u a schlaperl 04 ( . . . ) 131 Eurhynchlun praelongua var. s t o k e s l l 64 (2.1) Heterocladlua procurrens 39 ( . . . ) 132 Hookerfa lucens 92 ( . . . ) Isopterygiua elegans 15 ( . . . ) Isotheciua s t o l o n l f e r u a 92 ( . . . ) P l a g i o c h i l a asplenioides ?3 ( . . . ) 133 Pogonatuo l a t e r a l e 91 ( . . . ) Rhlzoanlua glabrescens 91 ( . . . ) 134 Rhlioanluo personil 84 (1.1) A n t i t r i c h i a curtipendula 7t ( . . . ) Calypogeia f l s s a 02 ( . . . ) 135 Calypogeia neesiana 02 ( . . . ) 136 Cephalozia blcuspldata 02 ( . . . ) 137 Cephalozia lasaerslana 02 ( . . . ) 138 Cephalozia plenlpes 91 ( . . . ) 139 Cladonia eactlenta It ( . . . ) Claopodlua bolanderi 78 ( . . . ) 140 Dendroalsla a b l e t l n a 71 ( . . . ) Dlcranua ho.el 1 i i 17 ( . . . ) Eurhynchlua praelongua var. atokesll 77 ( . . . ) T r u l l a n l a n l s g u a l l e n s l s 91 (...) Isopterygiua elegans 04 ( . . . ) 141 Jungeroannla lanceolate 77 ( . . . ) Leucolepls n e n z l e s l l 50 ( . . . ) 142 Lophozla Inclsa 23 ( . . . ) 143 Lophozla porphyroleuca 02 ( . . . ) Plaglocnlun Inslgne 17 ( . . . ) Plaglotheciua dentlculatua 78 ( . . . ) P o r e l l a cordaeana 90 ( . . . ) 144 R l c c a r d l a patoata 91 ( . . . ) Cephalozia eedla 23 ( . . . ) Dlcranua fuscescens 25 ( . . . ) 145 Dlplophyllun albicans 23 ( . . . ) 146 Olplophyllua o b t u s l f o l l u a 23 ( . . . ) Eurhynchlua praelongua var. s t o k e s l l 20 ( . . . ) Hoaalotheclua fulgescens 82 ( . . . ) Leucolepls c e n z i e s l l 82 (1.1) Heckera douglasii 77 ( . . . ) Plagionnlua venustua 62 ( . . . ) P l a g l c t h e c l u a dentlculatua 23 (...) 147 Pogonalua aacounll 23 ( . . . ) 148 Scapania aeerlcana 23 ( . . . ) Scapania bolanderi 21 (1.1) 149 Ihacnobryua l e l b e r g l l 20 ( . . . ) 75 (• .•) 91 (•.•) 12 (* .1) 25 (• . *) 77 (•.•) 150 A l e c t o r i a oregana Oendroalsia a b l e t l n a Homalothecius fulgescens 151 Hypnua subinponens 152 Hypogycnta physodes 153 Heckera c e n z i e s l l 154 Neckera pennata 155 P a r r e l l a s a x a t i l i s P o r e l l a cordaeana P t l l i d i u a p u t c t e r r l c u i 156 Radula bolanderi 157 Usnea c e r i t l n a A l e c t o r i a sarrentos* Cladonia c a c l l e n t a Cladonia ochrochlora 158 Claopodlua c r i s p i f o l l u a Dendroilsla abletina Dicranua hotelII1 Eurhynchlua orejani.B Eurhynchiya praelor.;t,e var. s t o k e s l i Hocalotreclun nuttal M l Hylocoslua splendent Hypnua S'^bicpor.ens P a r o e l l a s a x a t i l i s P l a g i o c h i l a asplenioides Plaglotneciue dentlculatua P l a t l s a a t l a stenophylta 159 P o r e l l a p l a t y p h y l l a Radula bolanderi Rhytidiadelphus loreus Rhytidiadelphus t r i q u e t r u s A n t i t r i c h i a curtipendula Cladonia s a c l l e n t a Claopodiuc c r i s p i f o l l u a Dendroalsla abietlna Dlcranua h o t e l l i i Lepidozia reptans Lotarla ore;ana Lophocolea heierophylla Kniua spinulosua lieckera pennata Plagiocniua cuspldata Plagioaniua Insigre Plagiosniua venustua PIaglothec.ua undulatua P o r e l l a cordaeana Radula bolanderi Rhizoaniua glabrescens Rhytidtadelphw t r l c u e t r u i 39 ( . . ) 50 (7 1), 52 (1.1) 82 (2 1) 52 ( . . ) . 71 ( . . . ) 75 ( . . ) , 77 ( . . . ) 52 (1 1) 32 (1 1) 92 ( . . ) 52 ( . . ) , 71 ( . . . ) 39 (• . ) , 91 ( . . . ) 50 (- • ) , 52 ( . . . ) 39 (• . ) 15 ( . . ) . 32 ( . . . ) 13 ( . . ) 73 (• . ) 75 1 . . ) 50 (1 1) , 52 (3.3) £2 ( . . ) 52 ( . •) 75 ( . . ) 15 ( . . ) , 52 (1.1) 52 ( . . ) 71 1 . . ) , 62 ( . . . ) 15 (• •) 25 (• . ) 32 ( . . ) . 92 ( . . . ) 77 (• • ) 75 (• . ) , 82 ( . . . ) 50 (• - ) , 82 ( . . . ) 20 ( . 71 ( « • ) , 82 ( . . . ) . ) 04 ( . . ) 04 ( . . ) , 32 ( . . . ) 62 ( . . ) 50 ( . . ) 32 (• .) 50 ( . . . ) . 91 ( . . . ) 14 ( . . • ) 20 ( . . . ) 25 ( . - ) , 32 11. .) 32 (• . . ) £2 (• 71 (* . . ) a (• '.•) 91 ( . . . ) , 92 ( 2 . . ) 52 ( . . . ) , 82 ( . . . ) 50 ( . . . ) 25 (• . . ) 71 (• . . ) Table 21a. General environment in Eurhynchio (oregani) - Tiarello (trifoliatae) -Polysticho (muniti) - Achlydo (triphyllae) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae achlydosum t r i p h y l l & e No. of plot: 1 2 3 4 5 6 7 Plot No.: 71 90 91 92 13 25 52 Elevation (m): 229 238 270 270 351 405 238 Exposure: N16E N66W S10E S 6 0 E S66W Slope gradient (°): 8 3 - - 5 20 8 Climate (estimated): Cfb , Biogeoclimatic unit: CWHa CWHa CWHa Light intensity (lux): 1381 1420 2204 1705 1095 Land form: base of al l u v i a l • • terrace .. alluv i a l base of all u v i a l slope fan fan slope fan Relief shape: .... straight ... • • • • f l a t .... straight . Drainage: well to moderate Hygrotope: Parent material: Thickness of humus (cm): Site index (m/100 years): Pseudotsuga menziesii  Tsuga heterophylla  Thuja plicata glacial alluvium 5-10 5-7 52 34 49 3-5 46 mesic to subhygric . glacial ... alluvium glacial 3-5 8-10 5-10 49 1*2 29 42 40 43 49 45 alluvium 5 - 8 56 32 25 Table 21b. General environment in Eurhynchio (oregani) - Tiarello (trifoliatae) -Polysticho (muniti) - Achlydo (triphyllae) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae gymnocarpiosum dryopteridis No. of plot: Plot No.: Elevation (m): Exposure: Slope gradient (°): Climate (estimated): Biogeoclimatic unit: Light intensity (lux): Land form: Relief shape: Drainage: Hygrotope: Parent material: Site index (m/100 years); Pseudotsuga menziesii  Tsuga heterophylla  Thuja plicata 8 02 320 9 Ok 320 N20W 3 2282 1829 .. base of slope .. fl a t , ... imperfect ... ... hygric ..... .. glacial t i l l . . 1*8 3k 31 5* k6 1*8 10 15 330 S 3 11 32 335 S30E 5 12 23 1+02 S80E 20 13 ll * 351 S10E 5 , Cfb , CWHb ., 1550 2103 alluvial fan.... 2369 base of slope 1637 , straight ,. moderate to imperfect , subhygric to hygric, alluvial deposits 51 37 1+9 50 glacial 52 37 37 52 37 l l * 1+6 390 N1+5W 33 2091* alluvial base of fan slope a l l u v i a l g l a c i a l colluvium 51* 1*5 Table 21c. General environment in Eurhynchio (oregani) - Tiarello (trifoliatae) - Polysticho (muniti) - Achlydo (triphyllae) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae polystichosum muniti No. of plot: 15 16 17 18 19 20 21 22 23 2h 25 Plot No.: 73 lh 75 8h 50 78 77 82 20 17 39 Elevation (m): 223 229 229 238 2hh 250 269 275 305 310 32 h Exposure: _ _ S S60W S85W W s46w S40E S78W S20E Slope gradient ( 0 ) : - - - 30 15 10 28 18 10 20 20 Climate (estimated): Biogeoclimatic unit: Light intensity (lux): Land form: Relief shape: Drainage: Hygrotope: Parent material: Thickness of humus: Site index (m/100 years): Pseudotsuga menziesii  Tsuga heterophylla  Thu.1 a plicata Cfb CWHa , CWHb 936 713 2 8 2 1 1 3 4 1 984 960 983 703 1539 842 768 .. a l l u v i a l fan .. ........ base of slope concave slope .. ... f l a t slightly undulating concave .... moderate .... ............ moderate to slightly imperfect ... subhygric subhygric to hygric .. a l l u v i a l deposits ............ glacial t i l l and outvash 1 0 - 1 2 5 - 7 3 - 5 3 - 5 5 - 1 0 10 10 1 0 - 1 5 5 - 1 0 5 - 7 1 0 - 1 5 54 54 54 46 43 46 46 34 46 45 46 39 55 32 56 42 50 40 Table 22. General c h a r a c t e r i s t i c s of s o i l s i n Eurhynchio (oregani) -T i a r e l l o ( t r i p h y l l a e ) - Polyst icho (muniti) - Achlydo ( t r i p h y l l a e ) - Pseudotsugo - Tsugo (heterophyllae) - Thujetum p l i ca tae Factor un i t of measurement minimum mean maximum pHt L-H horizon 4 . 2 4 . 9 5.6 A horizon 5 . 4 6.1 £ horizon 4 . 6 5.7 6.3 G horizon 5.2 5.9 6.5 Cation exchange capacityt humus m.eq./lOO g 4 2 . 3 9 ^ . 4 165.0 mineral s o i l s n 4 . 0 19.1 50.8 Total amount o f t calcium eq./cub. m. 7 . 4 32.9 79.1 magnesium n 2 . 4 6.0 13.9 sodium w 0.67 1 . 6 8 3 . 2 4 potassium w 0.21 0.65 1.38 organic matter kg/cub. m. 10.0 30.3 53.0 nitrogen g/cub. m. 2 3 8 627 965 ava i lab le phosphorus « 0.13 2.15 5 . 4 8 Base saturat iont humus per cent 13.9 31.8 65.3 mineral s o i l s M 6.1 39.0 1 6 8 . 0 * Carbon nitrogen r a t i o j humus 15 35 95 mineral s o i l s 7 2 8 78 F i e l d moisture % on volume bas is 5.9 22.3 50.6 F i e l d capacity n 9 . 4 23.8 37.0 Sand per cent 66.6 83.6 91.8 S i l t 6.0 13.9 29.2 Clay n 0.0 2 . 4 7 . 4 * probably the r e s u l t of f ree carbonate i n the s o i l Figure 27. The best growth of Pseudotsuga menziesii (168 cm in d.b.h. and 7^ m in height) on an a l -l u v i a l fan. Because the parent material contains limestone, base saturation of the s o i l is extremely high. The association is Eurhynchio (oregani) - Tiar e l l o (trifoliatae) - H Polysticho (muniti) - Achlydo (triphyllae) - Pseudotsugo - Tsugo (heterophyllae) - ^ Thujetum plicatae. (Plot 75, VIII 2, 1969) 110 occur on small a l l u v i a l fans which have been formed along lake edges at the mouth of streams. Parent material is mostly glacial t i l l and outwash, and some al l u v i a l deposits. Hygrotope of this association is rated as subhygric to hygric. Crown closure is very high in this association with an average cover of the A layer of 8l/L Thus, the light intensity under the forest canopy is the lowest among the associations with an average of 1U89 lux. The uppermost layer is dominated by Pseudotsuga menziesii, rarely mixed with Thuja plicata and Tsuga heterophylla. Trees, especially Pseudotsuga menzisii, are strikingly large in this association. Some of them attain more than 150 cm in d.b.h. and 7^ m in height. Particularly when they are growing on a l l u v i a l habitats where the parent material contains limestone. The large tree size is a conspicuous feature of the association. The layer consists of Pseudotsuga menziesii and Tsuga heterophylla, occasionally mixed with Thu.ja plicata. In the A^ layer, Tsuga heterophylla becomes dominant followed by Thu.1 a plicata. Pseudotsuga menziesii occurs only sporadically. Other companions in this layer are Acer macrophyllum, Abies grandis and Cornus  n u t t a l l i i . The layer is composed almost exclusively of Tsuga hetero- phylla. In the B^ layer, Tsuga heterophylla is again dominant. Besides i t , Vaccinium parvifolium and Mahonia nervosa occur constantly, Rosa gymnocarpa frequently. On moist habitats Oplopanax horridus is occasionally present. Of sporadic occurrences are Menziesia ferruginea, Vaccinium alaskaense, Abies  grandis. Cornus n u t t a l l i i . Rubus spectabilis. Rubus ursinus and Amelanchier  a l n i f o l i a . The coverage of the B layer is 29% on the average. The C layer is well developed with an average coverage of 65%, Fifty-four species are recorded in this layer. This would result from the richness in nutrients as well as water abundance. Achlys t r i p h y l l a is the dominant followed by Polystichum muniturn and T i a r e l l a t r i f o l i a t a . Disporum hookeri, Linnaea I l l borealis, Galium triflorum,Viola sempervirens. Trientalis l a t i f o l i a . T i a r e l l a  laciniata, Athyrium filix-femina and Lactuca muralis are frequently present. The occurrences of Adenocaulon bicolor. Smilacina s t e l l a t a . Adiantum pedaturn, Festuca subuliflora and Streptopus amplexifolius indicate the richness of the sites. The D layer on humus is relatively less developed, due to the high coverage of the C layer above i t , as an average cover of the D^ layer is 2 9 % . Eurhynchium oreganum is the dominant in this layer, followed by Hylocomium splendens and Rhytidiadelphus loreus. On moist habitats, Plagio- mnium insigne occurs frequently associated with Polystichum munitum. When habitats are slightly drier, Rhyt i di adelphus triquetrus and Mnium spinulosum are found occasionally. Because of highly shaded and moist habitats, the bryoflora on decaying wood is so diversified that fifty-one species were recorded in this layer. Hypnum circinale is the dominant, followed by Scapania bolanderi and Eurhynchium oreganum. Dicranum fuscescens and Rhytidiadelphus loreus are constantly present on decaying wood. Hylocomium  splendens, Isothecium stoloniferum, Rhizomnium glabrescens and Plagiochila  asplenioides are frequent. Cephalozia media, C_. leucantha and Lepidozia reptans are found occasionally on dead wood when i t i s well decayed. The development of the bryoflora on rocks i s moderate and the f l o r i s t i c compo-sition is more or less similar to that on humus. The frequent occurrences of Claopodium bolanderi, Heterocladium procurrens and H. macounii, again, indicate the richness of the substrata in basic minerals. Plagiomnium  venustum. Thamnobryum le i b e r g i i and Homalothecium fulgescens are also indic-ative of base-rich substrata, though they are sporadic. The epiphytic com-munities are well developed in this association. Especially the prepon-derance of Isothecium stoloniferum is a prominent feature of the association, which is indicative of high atomospheric humidity, Alectoria sarmentosa, 112 Lobaria oregana. Hypogymnia enteromorpha. Sphaerophorus globosus« and Platismatia glauca occur constantly in the upper canopy of the forests. The occurrences of Hypnum circinale. Dicranum fuscescens and Scapania  bolanderi increase more and more towards the bases of the trees. In the layer, however, the proportion of humicolous mosses such as Hylocomium  splendens and Rhyt i di adelphus loreus becomes higher. On the bark of Acer  macrophyllum. unique corticolous communities develop being composed of calcicolous epiphytes such as Dendroalsia abietina. Plagiomnium venustum. Homalothecium fulgescens. Claopodium bolanderi. Hypnum subimponens and Neckera menziesii. Other major constituents of the epiphytic layer include Antitrichia curtipendula. Neckera douglasii, Frullania nisquallensis, Porella navicularis. P. platyphylla. Radula bolanderi and Ptilidium  pulcherrimum. Soi l texture in the association is coarse as most of soils are loamy sand,.and. some are sand or sandy loam. There is a slight tendency toward increasing coarse texture with depth. The percentage of s i l t i s the highest among the associations as i t is lh% on the average. The general characteristics of the soils in the association are shown in Table 22. The pH value of humus, in general, is rather low with an average of U.9. That of the C horizon i s 5.9. Cation exchange capacity, total amounts of extract-able cations, nitrogen, carbon and available phosphorus decrease with depth. Most of the soils examined were found to be Brunisols (Dystric Brunisols), some of them were Gleysols and one case was found to be a Podzol. Three variations are recognized in this association, i.e. i ) achlyd-osum tri p h y l l a e , i i ) gymnocarpiosum dryopteridis, and i i i ) polystichosum muniti. 113 i) achlydosum triphyllae (Plot 13, 25, 52, 71, 90, 91, 92) This variant develops on gentle slopes on hillsid e s where the parent material i s predominantly glacial t i l l and outwash or rarely a l l u v i a l deposits. It i s differentiated from others by the high dominance of Achlys  tr i p h y l l a and frequent presence of Cornus canadensis. Rhytidiopsis robusta, Clintonia uniflora. Menziesia ferruginea. Chimaphila umbellata and Pyrola  secunda. It occurs on the driest habitats, comparatively, among the three variants. Its hygrotope is estimated to be the wetter part of mesic to the drier part of subhygric. This variant i s related to the moss association, especially to i t s variation hylocomiosum splendentis. Relatively high pro-portion of i t s f l o r a , therefore, consists of such species which belong es-sentially to the moss association. Most of the differential species described above are examples. The ecotopic characteristics of this variant are as follows: l) habitats are dry, comparatively the driest among the three variants; 2) their soils are poor in nutritional status: the total amount of magnesium content, organic matter, nitrogen, and available phosphorus in the soils is the lowest among the variants; 3) therefore, the base saturation both in humus and the mineral soils is the lowest among the variants, indicating that the seepage effect in this variant i s almost n i l . The consequence of this is a comparatively low productivity of the forest trees. The site index of Pseudo- tsuga menziesii is k& m/100 years; Tsuga heterophylla 39 m/100 years; Thuja  plicata 32 m/100 years in this variant. Soils are mostly Brunisols with one case being Podzol. I l l * Figure 28. Eurhynchio (oregani) - Tiarello (trifoliatae) -Polysticho (muniti) - Achlydo (triphyllae) -Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae achlydosum triphyllae occurs on com-paratively dry and depauperated habitats. Productivity of the forest trees is not very good. (Plot 90, IX 5, 1969) Figure 29. Eurhynchio (oregani) - Tiarello (trifoliatae) -Polysticho (muniti) - Achlydo (triphyllae) -Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae gymnocarpiosum dryopteridis is one of the communities occurring in the wetter subzone. Pseudotsuga :menziesii is the dominant followed by Thuja plicata and Abies amabilis. Tsuga  heterophylla is common on decaying wood. (Plot 23, IX 5, 1969) 115 i i ) gymnocarpiosum dryopteridis (Plot 0 2 , 0kt l h t 1 5 , 23, 32, 1+6) In this study area, the occurrence of this variant is confined to Elk River Valley area, where the climate is perhumid with annual total pre-cipitation of more than 2800 mm. Thus, the variant seems to belong to the wetter subzone of the coastal western hemlock zone. It occurs mostly on a l l u v i a l habitats where the parent material is fine a l l u v i a l deposits which are rich in s i l t , and topography is almost f l a t . Hygrotope of this variant is estimated to be subhygric. The water table is occasionally high so that i t may be found at a depth of 80 - 100 cm below the ground surface. This variant is differentiated by strong dominancy of Gymnocarpium  dryopteris and the frequent presence of Smilacina st e l l a t a , Vaccinium alaska-ense, Lactuca muralis» Viola glabella, Mnium spinulosum, Rubus spectabilis, Asarum caudatum, Trautvetteria carolinensis , Streptopus roseus, Actaea rubra, and Maianthemum dilatatum. Ecotopically this variant is characterized by l ) perhumid climate, 2) comparatively high water content in the soils due to a high water table and a relatively high proportion of s i l t in the s o i l s , 3) relatively high content of organic matter in the s o i l s ; the highest actually among the three variants, and consequently high cation exchange capacity, and 1+) the highest amount of calcium content in the soils among the three variants. Thus, pro-ductivity of the forest trees in this variant is f a i r l y high. The site index of Pseudotsuga menziesii is 51 m/100 years; Tsuga heterophylla l+lm/100 years; and Thuja plicata 1+0 m/100 years. Soils are mostly Gleysols. i i i ) polystichosum muniti (Plot 1 7 , 2 0 , 3 9 , 5 0 , 7 7 , 7 8 , 8 2 , 81+, 7 3 , lht 7 5 ) This variant is differentiated from the others by the remarkable high dominance of Polystichum muniturn and frequent occurrences of Galium t r i -116 Figure 30. Eurhynchio (oregani) - Tiarello (trifoliatae) -Polysticho (muniti) - Achlydo (triphyllae) -Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae polystichosum muniti occurs on hygric habitats where seepage effect i s present. Polystichum muriitum. Smilacina s t e l l a t a . Dis- porum hbokeri. Tiarella t r i f o l i a t a . Achlys  t r i p h y l l a . and Oplopanax horridus are indicative of rich habitats in mineral nitrients as well as water. They are characteristic species of Thujetalia plicatae. (Elk River Valley, VI 2 2 , 1 9 6 9 ) Figure 3 1 . Eurhynchio (oregani) - Tiarello (trifoliatae) -Polysticho (muniti) - Achlydo (triphyllae) -Pseudotsugo - Tsugo (heterophyllae) - Thujetum plicatae polystichosum muniti. Because of high stoniness and coarse texture, tree growth is not good. (Plot 2 0 , VIII 1 8 , 1968) 117 florum, Plagiomnium insigne, T i a r e l l a laciniata, Streptopus amplexifolius, Monotropa uniflora. Melica subulata and Montia s i b i r i c a . There are two different habitat types which support the develop-ment of this variant. One i s a seepage habitat type and the other is an all u v i a l habitat type. The difference in f l o r i s t i c structure between the two is rather slight. a. The seepage habitat type: This is generally found on slightly concave topography on moderate to steep slopes of the h i l l s i d e s . Occasionally, ravine-like areas with small streams may be present at the lowest part of depressions, although they may not be associated with well established streams as seen in the Oplopanax - Adiantum association. Parent material is glacial t i l l and outwash. The hygrotope is rated as subhygric to hygric. S o i l tex-ture is coarse as most of the soils are loamy sand or sand, and the stoniness is also high. Therefore, the water retention capacity as well as cation ex-change capacity of the soils is relatively low. On such habitats, therefore, seepage water which is accumulated due to the concavity of the topography plays an important role to sustain this kind of community. Actually, seepage water washing through the rhizosphere supplies the communities with enough nutrients as well as water to enable them to get established, even though the soils are very coarse. In some cases, however, seepage water may not be apparent during the summer dry season, when the size of the concavity i s not large enough to retain permanent seepage. This does not mean, necessarily, that the seepage is of less important. Temporary seepage after rain, es-pecially during the rainy season, plays the same role as permanent seepage. Thus, the "hydroponic effect" of seepage water is a controlling factor which maintain this type of community. I f there were no seepage effect on the habitats, there would not be this kind of community at a l l , and possibly the 118 moss association, especially the Mahonia type variant would have developed there instead. In general, the habitats are relatively rich in nutrients in spite of the coarse s o i l texture. Total amount of magnesium, sodium, nitrogen and available phosphorus is high. Base saturation both of humus and mineral soils is also high, indicating an influence of cation rich seepage. On the other hand, cation exchange capacity and total amount of calcium in the soils is very low, the lowest among the variants. This is probably due to the coarse texture of s o i l s . The productivity of the forest trees is not very high. It is somewhat lower than that of most of the "sword fern" sites. Site index of Pseudotsuga menziesii is h9 m/100 years; Tsuga hetero-phylla 38 m/100 years; and Thu.1a -plicata kk m/100 years. Unexpectedly low productivity could be a result of high stoniness and coarse texture of the soils and consequent low water retention capacity. In addition, the tempo-rariness of seepage could also be a cause of the low productivity in.this habitat type. b. The a l l u v i a l habitat type: There is a very different type of habitat $ which also support the development of the variant, that i s , an a l l u v i a l fan which is formed at the mouth of Marblerock Creek, facing Buttle Lake, and on which plots 73, lh and 75 were established. This is rather a peculiar case, since such an a l l u v i a l fan is usually more suitable for the variation achlydosum triphyllae than for the variation polystichosum muniti, because the habitats are too well drained and not sufficiently rich in nutrients for the variation polystichosum muniti. On this a l l u v i a l fan, however, the nu-t r i t i o n a l situation is very different from the usual cases. Parent ma-t e r i a l , which is obviously of a l l u v i a l deposits washed out by the fan-head I Figure 32. Excellent growth of Pseudotsuga menziesii on an a l l u v i a l fan formed by Marblerock Creek, facing Buttle Lake. Base status of H the s o i l is very high due to the parent material containing some N5 limestone. Compare with Figure 28: the case of usual a l l u v i a l fan. (Buttle Lake area, VIII 2, 1969) 120 stream Marblerock Creek, contains relatively high amount of limestone. The stream, indeed, cuts across a limestone bed which is located on the east side of the Marble Peak Mountain. Thus, the habitats are exceptionally rich in nutrients, especially in calcium. This is reflected by the high base sat-uration of the soils of the sites as, on the average, i t attains h0% in humus and 52$ in mineral s o i l s . This edaphic peculiarity strongly promotes the establishment of Pseudotsuga menziesii, even though the precipitation is high and the percolation of the soils i s extreme, since the loss of basic minerals is immediately compensated by those which are derived from the parent material. Furthermore, the high amount of precipitation acts rather as an important water supply on such stony habitats with coarse so i l s . Consequently, this a l l u v i a l fan provides the best habitats for Pseudotsuga  menziesii, and Tsuga heterophylla cannot compete with Pseudotsuga menziesii even though the climate is potentially more suitable for Tsuga heterophylla. The f l o r i s t i c structure, however, does not differ very much from the counter-part of the variant. Polystichum munitum shows a lower species significance and Achlys t r i p h y l l a has a higher species significance, instead, in this habitat type. Athyrium filix-femina. Plagjomnium insigne and Leucolepis  menziesii are almost lacking in this type, probably due to the dryness of the habitats, particularly of the upper strata of the s o i l s . Ecotopic character-i s t i c s are summarized as follows: l ) soils are very coarse as sand i s &9% of the fine earth, 2) low water content i n f i e l d , 3) low accumulation of organic matter, consequent low nitrogen content, k) high pH value, especially i n mineral s o i l s , 5) high base saturation both in humus and mineral s o i l s , and 6) high content of available phosphorus. The productivity is very high. Site index of Pseudotsuga menziesii 121 is 54 m/100 years. This is the highest value noted in the present study. That of Thuja plicata is 4 l m/100 years. Tsuga heterophylla is actually missing in the A-, and A Q layers in this habitat type. 6) OPLOPANACION HORFJDI Krajina in Brooke 1 9 6 6 , Brooke et a i . 1970 (6) Plagiomnio (insignis) - Leucolepido (menziesii) - Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae = the Oplopanax - Adiantum association (Plot 24, 2 6 , 30, 4 9 , 5 4 , 5 5 , 5 6 , 8 0 , 86) (Ref. Table 23, 2 4 , 25) Characteristic combination of species: Constant dominant species: Oplopanax horridus Constant species: Tsuga heterophylla Achlys t r i p h y l l a Galium triflorum Leucolepis menziesii Important companion species: Thuja plicata Viola glabella Adiantum pe datum Athyrium filix-femina  T i a r e l l a t r i f o l i a t a  Plagiomnium insigne Adenocaulon bicolor Eurhynchium praelongum var. stokesii This the h i l l s i d e s . association occurs on a l l u v i a l flood plains or in ravines on The water tables are always high in this association as most Table 23. PLAGIOMNIO (INSIGNIS) - THUJETUM PLICATAE - LEUCOLEPIDO (MENZIESII) - AOIANTO (PEDATI) - OPLOPANACO (HORRIDI) -No. of Plot 1 2 3 4 5 6 7 8 9 10 Plot No. 49 80 54 86 55 30 26 60 56 24 Slzo (m2) 300 300 600 300 800 150 600 600 600 450 Ciovatlon (m) 228 238 244 253 335 335 360 366 368 396 Exposure S66W - S80U N64W - S 3 M N85E - - E Slope gradient (degree) 16 - 12 6 - 25 18 - - 20 Average Strata coverage : A 30 65 70 60 80 50 58 75 52 52 59 B 95 95 80 50 90 93 60 95 80 53 79 C 77 60 80 90 37 59 65 24 34 84 61 Dh 67 54 34 75 13 30 37 27 51 58 45 Dd» 5 28 4 7 3 2 15 7 4 5 8 Or - - - - - 35 10 - - 10 6 Ground coverage : humus 91 65 92 89 56 37 62 76 89 66 72 mineral s o i l - - - - 12 . 5 - 5 - - 2 rock - _ - - - 40 15 - - 27 8 decaying wood 7 30 6 8 22 5 17 12 6 14 13 basal area 2 5 2 3 10 2 6 7 5 3 5 Number of s p e c i e s : 57 51 54 52 64 45 74 55 58 69 58 122 , Species Stratum ,, No. Species Species s i g n i f i c a n c e and s o c i a b i l i t y Presence Average Species S i g n i f i c a n c e A, 1 Thuja p l i c a t a _ 7.7 7.+ 7.8 _ 6.7 7.7 5.+ III 4.0 2 Pseudotsuga menziesii - 4.+ 6.+ 4.+ 6.+ 2.+ - - - III 2.2 3 Tsuga heterophylla - - - - 5.7 5.6 - 4.+ II 1.4 4 Abies amabi1is - - - - - 6.6 - 5.+ I 1.1 A2 Tsuga heterophylla - 4.+ 2.+ 5.+ 5.7 4.+ - 4.+ III 2.4 Abies amabilis - - 5.7 - - 6.5 5.+ - II 1.6 Thuja p l i c a t a - 6.+ - 3.+ - - 4.+ 5.+ II 1.5 5 Acer macrophyllum 4.+ 6.+ - - - - - - I 1.0 *3 Tsuga heterophylla 5.+ 3.+ 4.+ _ - 2.+ - - II 1.4 Abies amabilis - - 4.6 - 5.+ - - I 0.9 Acer macropnyl 1 urn 2.+ - - - - - - 0.4 Tsuga hoterophyl1 a _ 5.+ 2.+ 4.+ 4.5 - 4.+ 1.+ 4.+ 5.+ . IV 2.9 Abies amabilis - - 5.6 - 3.+ 5.+ +.+ - II 1.3 Thuja p l i c a t a 1.+ - 1.+ - - - - II 0.3 Acer macrophyllum - 5.+ - - - - 2.+ - I 0.7 B2 6 Oplopanax horridus 8.7 8.7 8.7 6.5 8.9 8.6 +.+ 8.7 8.8 5.5 V 6.7 Tsuga heterophylla 5.5 4.4 5.+ 4.+ 2.+ 6.5 3.+ - 5.4 IV 3.4 7 Vacciniun parvifolium 1.+ +.+ 1.+ 2.+ +.+ 5.5 4.5 - - 4.4 IV 1.7 8 Rosa gymnocarpa +.+ 1.+ 1.+ 2.+ 2.3 - 1.+ 1.+ - IV 0.7 9 Vaccinium alaskaense - - 4.5 - 4.5 4.3 3.4 III 1.5 10 Rubus p a r v i f l o r u s 2.+ 2.+ 2.+ 1.+ - - 1.+ • - +.+ 111 0.8 11 Mahonia nervosa +.+ 2.3 2.+ 2.3 +.+ - - +.+ III , 0.6 Abies amabilis - - 2.+ - 4.+ 4.4 - 4.+ II 1.4 12 Rubus s p e c t a b i l i s - 3.+ 2.+ 1.+ +.+ - - - II 0.6 13 Abies grandis 4.+ +.+ - - - - - - II 0.4 14 Ribes d i v a r i c a t u n - +.+ 3.+ - - - - - I 0.3 15 Arielanchier a l n i f o l i a - 1.+ 1.+ - - - - I 0.2 16 Cornus n u t t a l l i i +.+ 1.+ - - - - - - I . 0.1 C 17 Adiantum pedatum 7.6 6.5 7.5 9.8 5.4 6.6 1.1 4.5 6.5 V 5.1 18 Achlys t r i p h y l l a 5.5 3.2 4.3 2.+ 5.5 5.3 4.3 4.3 3.2 5.3 V 4.0 19 Athyrium f i l i x - f e r a i n a 1.+ 4.4 4.4 2.3 1.+ 4.2 2.4 1.+ 4.4 2.4 V 2.5 20 T i a r e l l a t r i f o l i a t a 2.+ 2.+ 2.1 +.+ 1.+ +.+ 2.2 1.+ - 4.1 V 1.4 21 Galium t r i f l o r u m 2.2 1.+ 1.+ +.+ +.+ +.+ - +.+ 1.+ +.+ V 0.5 22 Polystichum munitum 3.4 2.+ 5.4 1.+ 4.+ 4.4 - 1.+ 4.4 IV 2.4 23 Disporum hooker) 2.+ 2.+ 1.+ 4.4 - 3.+ 3.+ - IV 1.5 24 Adenocaulon b i c o l o r 3.+ 2.+ 1.+ +.+ +.+ 3.1 - +.+ 1.+ - IV 1.1 25 Cornus canadensis - +.+ +.+ 1.+ 3.1 +,+ 2.1 +.+ 2.3 IV 0.7 26 V i o l a g l a b e l l a +.+ +,+ +.+ +.+ - 1.+ 1.+ +.+ - IV 0.2 27 Streptopus amplexlfolius - "*;.+ +.+ +.+ 1.+ +.+ +.• - +.+ +.+ IV 0.1 28 Gymnocarplum dryopterls - 6.5 4.3 - 5.5 4.3 3.3 5.4 III 2.7 29 Smilacina s t e l l a t a - 3.2 4.2 - 1.+ - 3.+ 2.2 III 1.3 30 Linnaea boreal i s +.+ +.+ - 1.+ - +.+ - +.+ III 0.1 31 Trautvetteria carol 1nensts - - +.+ +.+ - +,+ +.+ III + 32 Lactuca mural i s - +.+ +.+ - +.+ - +.+ +.+ III + 33 T r i e n t a l i s l a t i f o l l a - 1.+ - - - 1.+ - II 0.2 34 C l i n t o n l a u n i f l o r a - - 1.+ - +.+ - +.+ - II 0.1 35 Goodyera o b l o n g i f o l i a - +.+ +.+ - +.+ +.+ - - - II + 36 Actaea rubra - +.+ +.+ - +.+ +.+ - - II + 37 Festuca'subuli-tlora- - • +.+ +.+ - - +.+ - - . II + 38 Veratrum vi ride - - 1.+ - - 1.+ - - I 0.2 39 Stenanthium o c c i d e n t a l i s - - 1.+ - - - - I 0.1 40 Chimaphila umbel l a t a - - - +.+ - - - I + 41 V i o l a sempervirens - - - - +.+ - - +.+ I + 42 Thalictrum o c c i d e n t a l i s - - - - - - 1 + 43 T i a r e l l a l a c i n i a t a +.+ - - - - - - 1 + 44 Streptopus roseus - - - - +.+ +.+ - - 1 + 45 Blechnum spicant +.+ - - - - - - +.+ 1 + 46 Oryopteris auctriaca - - - - +.+ - - +.+ 1 + Db 47 Plagiomnium insigne 2.1 5.1 5.1 1.+ 5.2 3.1 4.5 6.3 4.4 7.6 V 4.2 48 Leucolepis menziesii 7.5 6.3 4.2 7.6 1.1 6.4 +.2 - +.+ V 3.1 49 Eurhynchium praelongum var. s t o k e s ! i 3.2 +.+ 4.1 6.6 5.3 - 1.1 - IV 2.1 50 Eurhynchium oreganum 1.2 4.2 4.2 - 2.1 4.4 - - - III 1.5 51 Rhytidiadelphus loreus - - - 2.1 5.5 4.2 - 3.3 II 1.4 52 Hylocomium splendens 4.3 - - 3.3 1.+ - - +.+ II 0.8 53 Brachythecium lamprocryseum +.+ - 2.2 - - - 2.2 3.2 II 0.7 54 Rhytidiadelphus t r i q u e t r u s 4.3 1.+ - - +.1 - +.1 - II 0.5 55 Plagiothecium undulatum - - +.+ - 1.1 - - 1.1 II 0.2 56 P l a g i o c h i l a asplenioides +.+ - +.+ - i . 1 +.+ - - II 0.1 57 Chiloscyphus pallescens +.+ - +.+ +.+ - - +.+ - - II + 58 Rhizorani um glabrescens - - +.+ +.+ - +.+ - - II + 59 Rhizoiiinium perssonii - - 3.2 - - - 5.3 - 1 0.8 60 • Rhytidiopsis robusta - - 2.1 - - - - 1 0.2 61 Rhizoiiinium nudum - - +.+ - - 2.1 - - 1 0.2 62 Hookeria lucens - - - - +.+ - - 1.+ 1 0.1 63 Brachythecium asperrimum - - +.+ - - +.+ - - 1 + Dd» 64 Hypnum c i r c i n a l e 65 Scapania bolanderi 66 Dicranum fuscescens Rhytidiadelphus loreus Rhizomnlum glabrescens 67 Cephalozia leucantha 68 Cephalozia media P l a g i o c h i l a asplenioides Eurhynchium praelongum v a r , s t o k e s i i Eurhynchium oreganum 69 Lophocolea heterophylla Chiloscyphus pallescens 70 Mni um spi nulosum 71 Blepharostoma trichophyllum Hylocomium splendens Rhytidiadelphus triquetrus Plagiomni um insigne 72 Scapania unbrosa 73 Jamesoniella autumnal i s 74 Calypogeia f i s s a 75 Lepidozia reptans Leucolepis menziesii 76 Lophozia Incisa 77 Rhytidiadelphus squarrosus 78- Isothecium stoloniferum 79 Cephalozia lammersiana 80 Lophozia porphyroleuca 81 Calypogeia trichomanis 82 Heterocladium procurrens Dr Hylocomium splendens Plagiomnium insigne Rhytidiadelphus loreus Isothecium stoloniferum 83 Pogonatum macounii ' Rhizomnium glabrescens 84 Heterocladium macounii 85 Claopodium bolanderi P l a g i o c h i l a asplenioides Heterocladium procurrens E j Isothecium stoloniferum 86 'Lobaria orcgana 87 'Sphaerophorus globosus Dicranum fuscescens 88 A l e c t o r i a sarroentosa 89 Platismatia glauca 90 'Hypogyiani a enteromorpha 91 -Neckera douglasii Hypnum c i r c i n a l e 92 A n t i t r i c h i a curtipendula 93 F r u l l a n i a n i s q u a l l e n s i s 94 P o r e l l a n a v i c u l a r i s Scapania bolanderi 95 Cladonia ochrochlora Eg Hypnum c i r c i n a l e Dicranum fuscescens 'Sphaerophorus globosus Isothecium stoloniferum , P o r e l l a n a v i c u l a r i s Neckera douglasii Scapania bolanderi F r u l l a n i a ' n i s q u a l l e n s i s • A n t i t r i c h i a curtipendula . Hypogymnia enteromorpha , Lobaria oregana A l e c t o r i a sarmentosa Hypnum c i r c i n a l e Dicranum fuscescens Isothecium stoloniferum Scapania bolanderi Eurhynchium oreganum Rhytidiadelphus loreus ; P l a g i o c h i l a asplenioides P o r e l l a n a v i c u l a r i s Lepidozia reptans Heterocladium procurrens 1.1 4.4 2.3 2.2 +.+ 1.1 2.4 3.2 1.2 V 1.6 +.+ 4.4 2.3 2.2 +.+ 1.2 3.3 - +.1 1.3 V 1.3 1.1 +.1 +.1 +.+ +.+ 1.1 1.1 2.2 •.1 +.1 V 0.5 +.+ +.2 +.1 +.+ 2.5 - 4.3 - 1.1 2.3 IV 0.9 +.+ +.1 +.1 2.1 - +.+ 2.2 - +.+ - IV 0.4 +.+ - +.+ +.+ - +.+ +.+ . +.+ +.+ IV + +,+ - - +.+ +.+ - +.+ +.+ +.+ +.+ IV + +.+ 2.2 +.+ +.+ - - +.+ +.+ - - III 0.2 +.+ - +.+ +.+ - +.+ - - - 111 + - +.2 +.+ +.1 - - +.1 - - III + +.+ - - +.+ - - +.+ +.+ - III +.+ - +,+ - - - - +.+ III + - - - +.+ - +.+ - +.+ +.+ III + 3.2 2.1 3.1 1.1 1.1 1.+ 1.+ +.+ 1.1 2.1 1.1 5.4 +.+ 1.1 +.1 1.3 1.1 1.1 2.1 3.2 2.2 3.2 1.1 1.1 1.1 +.• 1.1 3.2 2.2 2.1 1.1 - - - + + +.+ 3.2 4.3 1.3 3.2 2.1 3.2 2.2 1.+ 4.3 - 2.2 1.+ - 1.+ 1.+ 1.1 +,+ -- +.+ +.+ - +.1 +.+ -+.+ +.+ - +.1 +.+ 1.1 _ 1.1 + + 1.1 2.1 +.+ +.+ +.+ + + 2.1 3.1 +.+ +.+ 3.+ 2.+ + .+ +.+ - +.+ 2.1 + + + ,+ +.+ +.+ +.+ +,+ 1.+ -- +.+ - + .+ 1.+ +.+ +.+ - + + •+ .+ -+.+ 2.+ 1.+ 2.1 3.1 1.1 III V IV IV IV IV 0.9 0.2 0.2 + 0.1 2.6 2.6 2.3 1.0 0.6 0.3 1.5 0.5 0.5 0.4 0.4 0.1 + 0.6 0.5 0.3 0.3 0.1 0.1 1.+ 1.+ 1.+ 2.+ 2.+ +.+ +.+ 3.2 V 1.3 1.+ +.+ 1.+ 1.+ 3.1 2.+ +.+ +.+ 2.1 V 1.1 +.+ +,+ +.+ +.+ 3.+ 2.+ +.+ - +.+ V 0.6 2.1 1.1 4.2 3.2 4.2 1.1 2.2 - - +.+ 1.+ - IV II 1.4 0.8 +.+ 4.2 2.2 - - - - - II 0.7 1.1 _ 1.1 2.1 - - II 0.4 2.2 +.+ - - - -1.+ II 0.3 0.1 2.1 2.1 2.1 3.2 2.1 2.1 3.1 ' 1.1 1.1 3.2 V 2.1 _ 2.1 2.1 2.1 +.+ 3.1 3.1 1.1 +.+ 2.1 V 1.5 2.1 +.+ 2.1 1.1 1.1 +.+ 2.1 1.1 +.+ - V 0 . 9 _ 2.1 1.1 3.1 _ 2.1 3.2 +.+ +.+ 2.1 IV 1.3 3.2 _ 1.1 1.1 1.1 +.+ - 2.1 +.+ - IV 0.8 _ 1.1 _ +.+ - - 4.2 +.+ 1.1 III 0.6 +.+ - +.+ - - - +.+ - - II + SPORADIC SPECIES: Abies grandis 49 (5.+) Or 127 Bartramia pomlformis 30 (• .•) Blepharostoma trichophyllum 24 (+.+) Abies grandis 54 (5.+) Calypogeia trichomanis 26 (•.+) Cephalozia leucantha 26 (+.•) Pseudotsuga menziesii 54 (3.+) Cephalozia media 26 (+.+) 128 Dichodontium pellucidum 30 (+.+) 96 Acer glabrum 80 (4.+) 129 Dlplophyllum albicans 26 (• .•) 97 Alnus rubra 55 (3.+) Eurhynchium praelongum var. s t o k e s i i 30 (5.3) Cornus nuttal1i i 49 (5.+) Hookeria lucens 26 (+.1) Pseudotsuga menziesii 80 (2.+) Jamesoniella autumnal i s 24 (+.+) Leucolepis menziesii 30 (6.3) Acer glabrum 55 (+.+) 130 Metzgeria conjugata 26 (•.•) Acer macrophyllum 56 (2.+) Mni um lycopodi oides 24 (1.2) Alnus rubra 55 (3.+) 131 Mnium marginatum 30 (+.+) 98 Gaultheri a shal1 on 86 (2.+) Mnium spinul osum 24 (+.+) 99 Menziesia ferruginea 49 (+.+) Plagiothecium denticulatum 24 (+.•) 100 Pinus monticola 49 (+.+) Plagiothecium pl 1 i ferum 26 (+.+) Pseudotsuga menziesii 80 (2.+) 132 P o r e l l a cordaeana 26 (+.+) 101 Rosa nutkana 55 (3.+) 133 Rhacomitrium heterostlchum 26 (1.1) 102 Rubus ursinus 49 (+.+) 134 Scapania americana 30 (•.•) Thuja p l i c a t a 80 (+.+) 135 Thamnobryum l e i b e r g i i 26 (1.1) 103 Botrychium virginianum 54 (+.+) EA 136 Dendroalsia abietlna 54 (2.1) 104 Carex deueyana 49 (+.+) 137 Homalothecium n u t t a l l i i 54 (+.•) 105 • Chimaphi1 a n e n z i e s i i 26 ( . . . ) 138 Neckera menziesii 54 (+.+) 106 Cinna l a t i f o l i a 24 (..+) P o r e l l a cordaeana 54 (+.+) 107 Circaea alpina 54 (+.+) 108 L i s t e r a cordata 86 (+.+) EB Cladonia ochrochlora 24 (+.+) 109 Luzula parvif1ora 24 (+.+) 139 Cladonia subsquamosa 24 (+.+) 110 Monotropa u n i f l o r a 26 (+.1) Claopodium bolanderi 54 (1.1) 111 Montia s i b i r i c a 54 (+.+) Dendroalsia abietina 54 (2.1) 112 Pyrola secunda 26 (+.+) Eurhynchi um oreganum 56 (2.1) 113 Smi1aci na racemosa 26 (+.+) 140 Lobaria pulmonarla 55 (+.+) 114 Streptopus streptopoides 60 (+.+) Mnium spinul osum 56 (+.+) 115 Tri setum cernuum 26 (•.+) Neckera menziesii 54 (+.•) Platismatia glauca 30 (+.+) Blepharostoma trichophyllum 55 (+.+) P o r e l l a cordaeana 54 (•.+) Calypogeia f i s s a 55 (+.+) Rhytidiadelphus loreuc 26 (+.+) Calypogeia trichomanis 60 (+.+) Rhytidiadelphus triquetrus 54 (1.1) 116 Drepanocladus uncinatus 55 (+.+) Heterocladium procurrens 60 (+.+) E C Cephalozia leucantha 80 +.+) Mnium spinulosum 24 (-.+) Cladonia ochrochlora 24 +.+) 117 Plagiothecium p i l i f e r u m 60 (+.+) 141 Claopodium c r i s p i f o l i u m 54 2.1) 118 Pohli a cruda 55 (+.+) Hylocomium splendens 86 1.1) 119 Riccardia palmata 86 (+.+) Mnium spinul osum 60 (•.+) 120 R o e l l i a r o e l l i i 60 (1.+) Neckera douglasii 54 (2.1) Plagiothecium denticulatum 55 (+.+) Brachythecium asperrimum 56 (+.+) 142 P t i l i d i u m pulcherrimum- 24 (•.•) 121 Calypogeia bicuspidata 86 (+.+) Sphaerophorus globosus 86 +.•) 122 Calypogeia neesiana 86 (+.+) 123 Cephalozia macounii 56 (+.+) Drepanocladus uncinatus 56 (+.+) 124 Jungermnnnia lanceolata 86 (+.+) 125 Mnium lycopodioides 24 (+.+) 126 Plagiothecium denticulatum 56 (+.+) Plagiothecium undulatum 56 (+.+) Riccardia palmata 86 (+.+) Table 24. General environment in Plagiomnio (insignis) - Leucolepido (menziesii) -Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae Ro. of plot: Plot No.: 1 4 9 2 8 0 3 5 4 4 8 6 5 5 5 6 30 7 2 6 8 6 0 9 5 6 1 0 2 4 Elevation (m): 2 2 8 2 3 8 244 2 5 3 3 3 5 3 3 5 3 6 9 3 6 9 3 7 7 3 9 6 Exposure Slope gradient(°): s66w 1 6 - S80W 1 2 N64w 6 - S30W 2 5 N85E 1 8 - - E 2 0 Climate (estimated): Biogeoclimatic unit: Light intensity (lux): Cfb . . . C W H R CWHb . . . 1 8 2 0 1377 3 2 1 6 2 7 6 3 2 0 0 8 3 3 2 6 1 7 6 9 1 6 0 8 1 6 8 3 2 3 1 6 Land form: Relief shape: Drainage: Hygrotope: Parent material: Thickness of humus (cm): Site index (m/100 years): Thuja plicata  Abies amabilis  Tsuga heterophylla ravine alluv. ravine ravine alluv. ravine ravine alluv. alluv. ravine concave f l a t .. concave .. f l a t .. concave f l a t ... concave saturated, running water may be present hygric to subhydric all u v i a l deposits 10-15 5 2-3 35-40 2-3 5-8 10 h9 4 0 46 4o 4 4 4 4 3 - 5 3 5 2 6 1 0 4 4 1 0 - 1 5 42 46 124 Table 25. General c h a r a c t e r i s t i c s of s o i l s i n Plagiomnio ( i n s i g n i s ) -Leucolepldo (menziesi i ) - Adianto (pedati) - Oplopanaco (ho r r id l ) - Thujetum p l i ca tae Factor u n i t of measurement minimum mean maximum pHt L-H horizon 5 . 5 6 . 2 6 . 7 A horizon 5 . 3 6 . 3 7 . 4 B horizon 5 . 9 6 . 4 6 . 8 C horizon 5 . 9 6 . 5 6 . 9 Cation exchange capaci ty ! humus m.eq./lOO g 8 2 . 7 1 2 7 . 9 1 6 8 . 0 mineral s o i l s « 8 . 8 2 7 . 0 5 7 . 8 Total amount of t calcium eq./cub. m. 2 8 . 1 7 3 . 9 1 2 9 . 1 magnesium M 4 . 1 1 0 . 5 3 3 . 8 sodium n 0 . 7 0 1 . 5 7 3 . 9 3 potassium n 0 . 2 1 0 . 4 2 0 . 6 8 organic matter kg/cub, m. 2 5 . 0 3 8 . 6 5 8 . 0 nitrogen g/cub. m. 2 3 8 8 8 0 1 6 8 0 ava i lab le phosphorus 0 . 3 8 1 . 1 7 2 . 5 1 Base s a t u r a t i o nt humus per cent 4 1 . 1 5 5 . 8 7 6 . 8 mineral s o i l s »• 1 7 . 9 6 1 . 2 1 2 4 . 0 » Carbon nitrogen r a t i o t humus 2 2 32 4 3 mineral s o i l s 9 2 6 8 6 F i e l d moisture % on volume basis 1 7 . 5 4 4 . 7 9 6 . 7 F i e l d capacity N 1 8 . 5 2 6 . 8 3 3 . 7 Sand per cent 8 0 . 9 8 7 . 0 9 4 . 9 S i l t I I 3 . 2 1 1 . 9 1 6 . 5 Clay «• 0 . 0 1 . 1 2 . 7 * probably the r e s u l t of f ree carbonate i n the s o i l 125 Figure 33. Plagiomnio (insignis) - Leucolepido (menziesii) -Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae, occurring on an a l l u v i a l flood plain along Wolf River. This habitat is extremely rich in mineral nutrients due to a parent material containing limestone. Tree growth is excellent. The dominant tree is Thuja plicata accompanied by Pseudotsuga menziesii. (Plot 5 5 , VII 1 7 , 1969) Figure 34. Plagiomnio (insignis) - Leucolepido (menziesii) -Adianto (pedati) - Oplopanaco (horridi) - Thujetum plicatae occurs on ravine types of habitats where i t forms narrow bands along streams. (Plot 5 4 , VII lk, 1969) 126 of them are found at a depth of 30 - 50 an below the ground surface, and in some cases, water i s flooded almost up to the ground surface. Running water may he present in some cases. Thus, the hygrotope of this association is rated hygric to subhydric. There are two different habitat types on which this association develops. One is a l l u v i a l flood plain type, and the other is ravine type of habitat. The former type is recognized along the rivers, especially on the point bar deposit of a meander, where the parent material is relatively fresh a l l u v i a l deposits with low stoniness, and the topography is f l a t . The latter is found in ravines where parent material is a very coarse a l i u v i a l deposits with high stoniness, and the topography i s sloping with an average of l6 degrees ranging from 6-25 degrees. The f l o r i s t i c difference between the two is rather minor. The uppermost layer of the forest canopy is mainly composed of Thu.la plicata. mixing with Pseudotsuga menziesii. Tsuga heterophylla occa-sionally participates in this layer. Abies amabilis*and Abies grandis* may occur sporadically depending upon the lo c a l conditions. In the A^ and A^ layers, Tsuga heterophylla is the dominant, accompanied by Thuja plicata and Abies amabilis. Sporadically Acer macrophyllum may occur in the layers. The crown closure of the A layer i s low, as the average i s 60% % ranging from 30$ to 8 0 % , because the communities frequently develop close to streams or facing streams where no tree is actually standing. Light intensity, there-fore, is relatively high with an average of 2188 lux, ranging from 1377 to 3216 lux. The layer is composed mainly of the constituents of the tree layer with some occurrences of Acer macrophyllum, Cornus n u t t a l l i i and Alnus rubra. The B layer is very well developed, prevailingly dominated by . 2 Oplopanax horridus which is followed by Tsuga heterophylla. Vaccinium parvi-folium, Rosa gymnocarpa. Rubus parviflorus, Mahonia nervosa and Vaccinium * Abies amabilis represents the wetter subzone, whereas Abies grandis grows i n the drier subzone of the coastal western hemlock zone. 127 alaskaense are occasionally found in this layer. The distribution of Vaccinium alaskaense seems to be controlled by the amount of precipitation rahter than by the edaphic conditions. The sporadic occurrences of Abies  amabilis and Abies grandis are also dependent upon the climatic conditions. The average cover of the B layer is 79$ in the association. The C layer is relatively well developed covering 6l# on the average. Forty-two species are recorded in the C layer. Adiantum pedatum is the dominant which well characterizes the association. Achlys t r i p h y l l a . Athyrium filix-femina. T i a r e l l a t r i f o l i a t a and Galium triflorum are constant (but not dominant) species. Adenocaulon bicolor, Polystichum munitum, Disporum hookeri, Cornus  canadensis„ Viola glabella and Streptopus amplexifolius are frequently asso-ciated with the association. Gymnocarpium dryopteris. Smilacina s t e l l a t a , Trautvetteria carolinensis and Lactuca muralis are found occasionally. Besides them, though their occurrences are infrequent, Actaea rubra, Festuca  subuliflora and Trientalis l a t i f o l i a are indicative of the richness of the habitats in nutrients as well as water. The D layer on humus is well developed. It includes Plagiomnium insigne. Leucolepis menziesii and Eurhynchium  praelongum var. stokesii. a l l of which are indicative of the wet and rich habitats and are characteristics of the association. Eurhynchium oreganum is found occasionally. The occurrences of Hylocomium splendens, Brachythecium  lamprochryseum. Rhyt i di adelphus loreus, Rhyt i di adelphus triquetrus. Plagio- thecium undulatum. Plagiochila asplenioides and Chiloscyphus pallescens are sporadic. Though their occurrences are rather rare, Brachythecium  asperrimum. Rhizomnium perssonii, Riccardia palmata, Rhizomnium nudum and Hookeria lucens are highly associated with this association. The D layer on decaying wood is well developed, having forty-two species recorded. Nineteen 128 species of these were liverworts. Hypnum circinale, Dicranum fuscescens and Scapania bolanderi occur constantly. Rhytidiadelphus loreus. Rhizomnium glabrescens. Cephalozia leucantha and Cephalozia media are frequent. On rocks, Hylocomium splendens and Plagiomnium insigne are co-dominant, followed Rhyt i di adelphus loreus. Isothecium stoloniferum. Pogonatum macounii and Rhizomnium glabrescens are relatively common. The epiphytic layer is not well developed in this association. Constant occurrence of Isothecium stoloniferum hanging on branches indicates the high atomospheric humidity in the sites. Dicranum fuscescens. Hypnum circinale and Sphaerophorus globosus are constantly found on the trunks of conifers in the E and E A B layers. In the E^ , layer, the proportion of essentially humicolous mosses to others increases. Eurhynchium oreganum and Rhyt i di adelphus loreus are the examples. Productivity of the association i s high as site index of Thuja  plicata is kk m/100 years; that of Pseudotsuga menziesii ^ 3 m/100 years; and that of Tsuga heterophylla 35 m/100 years. In this association, s o i l texture is coarse, most of the soils are sand while some are loamy sand. There is no particular tendency toward increasing coarseness with depth. Stoniness is high in the ravine type of habitats, but i t is low in a l l u v i a l flood plain habitats. General character-i s t i c s of the soils are shown in Table 25. In general, the pH value of humus is significantly higher than those of other associations. Base saturation in the association i s especially high. On the average i t is 55.8$ in humus, and 6l.2% in mineral s o i l s . Both of the values are significantly higher than those of other associations. The carbon-nitrogen ratio of humus is 32, that of mineral soils i s 26, both of which are not significantly different 129 Figure 35 • Oplopanax horridus and Adiantum pedatum (Plot 24, VIII 2 5 , 1968*5 Figure 3 6 . A s o i l profile in Plagiomnio (insignis) -Leucolepido (menziesii) - Adianto (pedati) -Oplopanaco (horridi) - Thujetum plicatae, showing high water table with permanent seep-age and thick accumulation of well decomposed organic matter. (Plot U 9 , VII 7» 1969) 130 from those of other associations. As is mentioned earl i e r , there are minor differences in f l o r i s t i c structure between the flood plain type and ravine type of habitats. For instance, Disporum hookeri. Gymnocarpium dryopteris. Smilacina s t e l l a t a . Viola glabella. Actaea rubra. Thalictrum occidentalis and Veratrum viride are more associated with the former type of habitats than with the l a t t e r , while Leucolepis menziesii. Eurhynchium praelongum var. stokesii, Festuca subuli-flo r a , T i a r e l l a laciniata and Hookeria lucens tend to associate with the latter. Hylocomium splendens. Eurhynchium oreganum. Rhyt i di adelphus t r i - quetrus . Goodyera oblongifolia. Chimaphila umbellata. Viola sempervirens and Blechnum spicant also seem to associate with the latter. These species, however, do not belong to this association necessarily, but they are acci=-. dentally included here in the ravine type, because the association develops forming narrow strips along the streams, and in the ecotone, i t changes intricately into other association, forming a "mosaic complex" depending upon the micro-topography. The frequent occurrences of Pseudotsuga menziesii in the A^ layer in this association are also the cases in which parts of the crowns of Pseudotsuga menziesii. which belong essentially to other communi-t i e s , invade in this association and cover i t . This association i s somehow comparable to Abieteto - Oplopanacetum (Orloci 196l) which develops in the ravines where steep slope and coarse parent material prevent the development of the Lysichiturn americanum ccramuni-t i e s . This association i s , however, distinguished from Orloci's by the presence of Achlys t r i p h y l l a . Galium triflorum, Plagiomnium insigne. Leuco- lepis menziesii. Eurhynchium praelongum var. stokesii. and the absence of Lysichiturn americanum, Vaccinium ovalifolium. Conocephalum conicum and Sphagnum squarrosum on the other hand. 131 7) LYSICHITION AMERICANI Krajina in Brooke 1 9 6 5 , Brooke et a l . 1970 (7) Sphagno (girgensohnii) - Rhizomnio (perssonii) - Lysichitetum americani - the Lysichiturn americanum association (Plot 1*3, hk, 1*5) (Ref. Table 2 6 , 2 7 , 2 8 ) Characteristic combination of species: Constant dominant species: Vaccinium alaskaense  Sphagnum girgensohnii Constant species: Tsuga heterophylla  Streptopus amplexifolius  Rhizomnium perssonii Important companion species: Trautvetteria carolinensis Lysichitum americanum Coptis asplenifolia  P e l l i a neesiana Rhizomnium nudum Athyrium filix-femina This association is found only in limited small locations in the Heber River Valley, surrounded completely by the Vaccinium alaskaense asso-ciation. It occurs on small basin-like depressions where water stagnates, probably due to the development of hard pans which impede the percolation of water. Extremely poor drainage and aeration result in a thick accumulation of amorphously decomposed organic matter in the form of black muck or hanging anmoor (Kubiena 1 9 5 3 ) . This kind of organic s o i l provides a particular habitat which is known as the "skunk cabbage" site. Due to the extremely poor drainage and aeration, the tree layer i s poorly developed. On humps, T.bli 26. No. of plot SPHAGNO (GIRGENSOHNII) - RHIZOMNIO (PERSSONII) . LYSICHITETUM AMERICANI Plot. No. 45 44 43 Plot size (n2) 100 100 150 Elevation (n) 400 405 408 Exposure - - - Average Slope gradient (degree ) - - -Strata coverage (?) : A - 10 3 8 40 75 30 48 C 95 80 95 90 Dh 30 46 45 40 Odi 15 12 17 14 Dr - - - -Ground coverage (%): humus' 75 80 70 75 mineral soils - - 5 2 rock - - - -decaying Hood 25 20 25 23 Number of species 27 23 32 27 Stratum Species No. Species Species significance and sociability Presence Average . sp. sign. 1 Tsuga heterophylla - - 4.+ II 1.3 Tsuga heterophylla - 6.5 5.5 IV 3.6 2 Abies amabilis 3.+ - - II 1.0 3 Vaccinium alaskaense 6.5 6.6 5.4 V 5.8 Tsuga heterophylla 3.+ 5.5 3.+ V 3.6 4 Rubus spectabilis 3.+ - 1.+ IV 1.3 5 Menzlesla ferruglnea - 2.+ 2.+ IV 1.3 6 Oplopanax horridus 4.+ - - II 1.3 7 Sorbus sitchensis - +.+ - II + 8 Viburnum edule - - +.+ II + 9 Lyslchitum americanum 8.7 8.7 8.7 V 8.0 10 Coptis asplenifolia 3.2 4.2 3.1 V 3.3 11 Streptopus amplexifolius • 2.+ 1.+ +.1 V 1.3 12 Athyrlum flllx-femlna 5.5 • - 6.5 IV 3.6 13 Trautvetterl a carol inensis 3.2 - 3.1 IV 2.0 14 Viola palustris - 3.+ +.+ IV 1.0 15 Cornus canadensis - 2.1 1.+ IV 1.0 16 Clinton!a uniflora - 2.+ +.+ IV 0.7 17 Rubus pedatus - 1.+ +.+ IV 0.3 18 Listera cordata - +.+ +.+ IV + 19 Gyranocarplum dryupterls 2.+ - - II 0.6 20 Blechnum splcant - - 2.2 II 0.6 21 Maianthemum dilatatum - - 2.+ II 0.6 22 Tiarella tr! foi lata 1.+ - - II 0.3 23 Menyanthes trifoilata - - II + 24 Veratrum vlride - - II + 25 Caltha Mflora - - +.+ II + 26 Sphagnum girgensohnii 6.4 6.4 6.4 V 6.0 27 Rhizomnium perssonii 6.3 4.3 3.2 V 4.3 28 Pell 1 a neeslana 5.1 3.2 4.2 V 4.0 29 Rhizomnium nudum 2.1 2.1 1.1 V 1.6 30 Chlloscyphus pallescens +.+ - +.+ IV + 31 PIagiotheci um denticulatum +.+ - IV + 32 Sphagnum russowii - - II 33 Cephalozia nacounll - - II + 34 Sphagnum squarrosum - - +.+ II + 35 Rhytidiadelphus loreus 5.3 4.2 3.2 V 4.0 36 Dicranum fuscescens 2.1 2.1 4.2 V 2.6 37 Hypnum circinale +.+ +.+ 3.1 V 1.0 38 Blepharostoma trichophyllum +.+ +.+ +.+ V + 39 Cephalozia leucantha +.+ - +.+ IV + 40 Cephalozia modi a +.•*• - +.+ IV + 41 Scapania bolanderi +.+ ' - - II + 42 Lophozia inclsa +.+ - - II + 43 Lophozia porphyroleuca +.• - - II •f Table 27. General environment in Sphagno (girgensohnii) -Rhizomnio (perssonii) - Lysichitetum americani No. of plot: Plot No.: Elevation (m): Exposure: Slope gradient (°): Climate (estimated): Biogeoclimatic unit: Land form: Relief shape: Drainage: Hygrotope: Parent material: Thickness of humus (cm): 1 2 3 1+5 kk 1+3 1+00 1+05 *+08 Dfb CWHb depression concave extremely poor hydric .... glacial deposits .... 1+5+ 60+ 55+ 13k. Table 28. General c h a r a c t e r i s t i c s of s o i l s i n Sphagno (girgensohni i ) -Rhizomnio (perssoni i ) - Lysichitetum americanum Factor u n i t of measurement minimum mean maximum pH value 3.9 * . 8 5 . 7 Cation exchange capacity m.eq./lOO g 1 0 . 3 6 1 . 3 1 0 4 . 0 Total amount oft calcium eq./cub. m. 3 . 7 1 * . 7 3*.* magnesium n 1 . 3 **.l 8 . 3 sodium n 0 . 7 5 0 . 9 ^ 1 . 1 0 potassium n 0 . 2 4 0 . 6 6 1 . 0 4 organic matter kg/cub, m. 5 8 . 4 6 7 . 7 7 8 . 4 nitrogen g/cub. m. 8 4 0 1776 2331 ava i lab le phosphorus w 1 .93 3 . 6 6 6 . 6 2 Base saturat ion per cent 2 . 4 17 .0 4 0 . 2 Carbon nitrogen r a t i o 10 39 2 0 5 F i e l d moisture % on volume bas is 8 4 . 7 9 3 . 1 109 .7 F i e l d capacity n 30.9 3 ^ . 0 50.3 135 Figure 37. Sphagno (girgensohnii) - Rhizomnio (perssonii)-Lysichitetum americani, occurring on basin-like depressions where water stagnates and thick amor-phously decomposed organic matter in the form of "black muck" accumulates. (Plot 1,3, VI 2 1 , 1969) Figure 38. Sphagno (girgensohnii) - Rhizomnio (perssonii) -Lysichitetum americani. (Plot hk, VI 2 1 , 1969) 136 where habitat condition is comparatively drier, stunted trees of Tsuga hetero- phylla and Abies amabilis may be present. The layer is f a i r l y well deve-loped as Vaccinium alaskaense is always present on humps, followed by Rubus  spectabilis and Menziesia ferruginea. Coverage of the B layer i s , on the average, k8%. The C layer i s very well developed and i t has a distinctive f l o r i s t i c structure which characterizes the association extremely well. The dominant species is Lysichitum americanum which gives the association a unique appearance. Coptis asplenifolia and Streptopus amplexifolius are constantly present. Athyrium filix-femina. Trautvetteria carolinensis and Viola palustris are found in this association. On humps, Cornus canadensis. Clintonia uniflora. Listera cordata and Rubus pedatus grow frequently. These species are essentially the elements of the Vaccinium alaskaense asso-ciation. Sporadic occurrences of Menyanthes t r i f o l i a t a . Maianthemum  dilataturn. Veratrum yiride and Caltha b i f l o r a are indicative of very moist habitats. On the ground surface where the substratum is black muck, Sphagnum  girgensohnii is the dominant, accompanied by Rhizomnium perssonii. P e l l i a  neesiana and Rhizomnium nudum. Sphagnum russowii and Sphagnum squarrosum are occasionally present. On decaying wood, which is rather rare in this association, the species which belong essentially to the Vaccinium alaskaense association are commonly growing. The following are examples: Hypnum  circinale. Rhytidiadelphus loreus. Dicranum fuscescens. Cephalozia media, £. leucantha and Blepharostoma trichophyllum. Soils in the association are organic soils with a thick accumula-tion of well decomposed organic matter (black muck) with a depth of 50 - 60 cm. The total amount of organic matter as well as nitrogen, therefore, is extremely high with an average of organic matter being 68 kg/cubic metre of 137 s o i l and that of nitrogen being 1776 g/cubic metre of s o i l , both of which are the highest values among the associations. Available phosphorus is also very high in the association with an average of 3.68 g/cubic metre of s o i l . The carbon-nitrogen ratio in the association is very variable ranging from 10 to 205 with an average of 39. This extremely high value is probably due to the loss of nitrogen by microbial activities during the air drying process, since the muddy organic matter rarely dries in nature. General character-i s t i c s of soils are shown in Table 28. As this association is completely surrounded by the Vaccinium  alaskaense association and i t covers relatively small area confined to specific topographical situation, i t s f l o r a includes considerable amount of these species which essentially belong to the elements of the Vaccinium  alaskaense association. This does not mean, however, that i t has particular a f f i n i t y to the Vaccinium alaskaense association principally. These species are accidental companions occurring on humps and decaying wood where habitat conditions are entirely different from black muck substratum. Ecotopically this association is quite different from the Vaccinium alaskaense association in the following respects that: l ) soils are organic soils with thick accu-mulation of amorphously decomposed organic matter, 2) hygrotope is rated as hydric, and 3) nutritionally the habitats are very rich in mineral nutrients. This association has a close a f f i n i t y to the Lysichitum - Coptis forest type which was described by Orloci (1961, 196U). It i s , however, distinguished from that in the following respects: l) the strong develop-ment of the herb layer with an average of 75$• 2) a poorly developed tree layer, 3) the high dominance of Sphagnum girgensohnii on the ground surface. These differences would be the result of different habitat conditions, i.e. 138 thick accumulation of black muck substratum in this association which i s un-favorable for tree growth because of poor drainage and aeration. This association i s also closely related to Lysichito (americani) - Chamaecyparetum nootkatensis described by Brooke (1966, Brooke et a l . 1970), which is found in the lower portion of the Mountain Hemlock zone on such habitats where water stagnates in depressions and black muck type organic matter i s accumulated. This association i s , however, distinguished from that again by: l ) the poorly developed tree layer, 2) the complete absence of the subalpine elements such as Chamaecyparis nootkatensis, Tsuga  mertensiana, Vaccinium membranaceum and Vaccinium ovalifolium, and 3) the high dominance of Sphagnum girgensohnii. i 139 k. SPIRAEO - MYRICETALIA GALIS Kojima & Krajina This order represents low moor communities. Its occurrence in the study area is confined to a margin of Drum Lakes, where soils consist of a mixture of gravel and drifted organic debris. Hygrotope i s estimated as hydric to subaquatic when water level of the lakes is high, and subhydric to hygric when the water level is low. The following are the characteristic combination of species: Myrica gale Viola palustris Spiraea douglasii Campylium polygamum Carex sitchensis Drepanocladus revolvens Galium trifidum Fissidens adianthoides Hypericum formosum One alliance and one association were recognized in the study area. 8) SPIRAEO (DOUGLASII) - MYRICION GALIS Kojima & Krajina (8) Campylio (polygami) - Carico (sitchensis) - Spiraeo (douglasii) - Myricetum galis = the Myrica gale association (Plot 9k, 95, 96, 97, 98, 99) (Ref. Table 29, 30, 31) Characteristic combination of species: Constant dominant species: Myrica gale 140 Constant species: Spiraea douglasii Carex sitchensis Viola palustris Campylium polygamum Fissidens adianthoides Important companion species: Hypericum formosum Galium trifidum This association occurs along the shore of Drum Lakes which are located close to the Elk River Valley. It occurs on the habitats immersed in water during the rainy season when the water level rises, but emergent from the water in the summer dry season. Parent material is predominantly sand and gravel deposited on beach. Frequently, drifted organic debris is mixed with the gravel. The tree layer is completely absent. The layer consists overwhelmingly of dense thickets of Myrica gale. Spiraea  douglasii occurs constantly in this layer. Rubus spectabilis, Alnus rubra, Physocarpus capitatus, Pyrus fusca, Viburnum edule and Cornus stolonifera are found sporadically. The C layer is not very well developed, probably due to the high coverage of the B layer above i t . Carex sitchensis i s , how-ever, comparatively dominant, associated with Viola palustris. Hypericum  formosum and Galium trifidum are frequent. companions. Other occasional and sporadic occurrences include Mentha arvensis, Veronica scutellata, Aster  modestus and Agrostis thurberiana. The development of the moss layer i s extremely poor with an average cover of the D layer being 2%. Campylium h polygamum and Fissidens adianthoides constantly occur on plant residues which cover the ground surface. The soils are rather heterogeneous in texture and content of organic matter, due to the turbulence caused by the lake water and fluctu-141 Table 29, CAMPYLIO (POLYGAMI) -CARICO (SITCHENSIS) -SPIRAEO (DOUGLASII) - MYRICETUM GALIS No. of P l o t 1 2 3 4 5 6 P l o t No. 94 95 96 97 98 99 P l o t s i z e (ra2) 25 25 25 25 25 25 E l e v a t i o n (m) 295 295 295 295 295 295 Exposure _ • - _ m _ Slope gradient (deg •ee) - - - - - - Average S t r a t a coverage (2) . A - - _ -B 96 85 60 95 93 95 90 C 6 16 25 22 8 23 17 Dh 5 1 2 1 + + 1 Dd« - - - _ -Dr - - - - - -Ground coverage {$) humus 99 90 95 100 100 100 97 mineral s o i l - 10 5 - - - 2 rock - - - - - -decaying «ood 1 - - - - - + basal area + + + + + + +• Number of s p e c i e s : 11 10 14 14 10 7 11 Stratum Species No. Species Species s i g n i f i c a n c e and s o c i a b i l i t y Presence Average Species S i g n i f i c a n c e h 1 Myrica gale 9.9 9.1 9.1 9.1 9 . 9 . 9 . 1 V 9 . 0 2 Spiraea d o u g l a s i i 4.5 4.4 4.+ 2.+ 4.+ 3.+ V 3.5 3 Alnus rubra - 2.+ 3.+ - - II 0 . 8 4 Rubus s p e c t a b i l i s +.+ - +.+ - - II + C 5 Carex s i t c h e n s i s 4 . 6 4 . 6 4 . 6 3.5 4 . 5 5 . 5 V 4 . 0 6 V i o l a p a l u s t r i s +.+ 1.+ 2.2 4 . 2 +.+ . - V 1 .2 7 Hypericum formosum 3.+ 3.+ 3.+ +.+ IV 1.5 8 Galium t r i f i d u m +.+ 2.1 2.+ 3.+ IV 1.2 9 Mentha arvensis - 2.+ 2.+ - - - - II 0.7 10 Veronica s c u t e l l a t a - - 2.+ +.+ • - II 0 . 3 11 Aster modestus - - +.+ +.+ II + 12 Agrostis thurberiana - - +.+ +.+ - II + Dh 13 Caupylium polygamum 2.1 +.+ 2.1 2.1 +.+ +.+ V 1.0 14 F i s s i d e n s adianthoides 2.+ +.+ +.+ +.+ +.+ V 0 . 3 15 Orepanocladus revolvens 2.1 1.+ - - - II 0.5 SPORADIC SPECIES: 16 Cornus s t o l o n i f e r a 94 (+.+) C 20 Carex oederi v a r . v i r i d u l a 96 (1.+) 17 Physocarpus c a p i t a t u s 94 (3.+) 21 Carex r o s t r a t a 96 (+.+) 18 Pyrus fusca 94 (2.+) 22 Gentiana sceptrum 95 (+.+) 19 Viburnum edule 94 (+.+) 23 Juncus f a l c a t u s 96 ( 3 . 3 ) Dh 24 Bryum binum 94 (1.+) 142 Table 30. General environment in Campylio (polygami) - Carico (sitchensis) - Spiraeo (douglasii) - Myricetum galis No. of plot: 1 2 3 4 5 6 Plot No.: 94 95 96 97 98 99 Elevation (m): 295 Exposure: _ _ _ _ _ _ Slope gradient ( 0 ) : Climate (estimated): Cfb Biogeoclimatic unit: CWHb Land form: lake shore Relief shape: f l a t Drainage: poor Hygrotope: ............. hydric Parent material: mixture of beach gravel and drifted organic debris Thickness of humus (cm): ? 0-1 0-1 2 0-1 0-1 143 Table 3 1 . General c h a r a c t e r i s t i c s of s o i l s i n Campylio (polygami)— Carico (s i tchens is ) - Spiraeo (douglas i i ) - Myricetum g a l i s Factor u n i t of measurement minimum mean maximum pH value 4 .9 5 .3 5.7 Cation exchange capacity m.eq./lOO g 2.9 21.4 73.7 Calcium* u 1.33 8.08 51 .00 Magnesium* M 0.14 1.48 6.80 Sodium* 0.28 0.48 0.74 Potassium* I t 0.00 0 . 0 5 0.40 Carbon* per cent 0.1 12.5 2 7 .1 Nitrogen* i t 0.01 0 . 3 1 0.94 Ava i lab le phosphorus* ppm 0 2 5 Base saturat ion per cent 6 .9 44.8 104.0 Carbon nitrogen r a t i o 5 29 117 Sand per cent 64.0 85.8 98.8 S i l t •• 1.2 11.3 33.4 Clay 0.0 2.8 7.0 * because of lack ing the data of bulk dens i ty , these factors are not converted in to volume b a s i s . Ikk Figure 39. Drum Lakes, showing Campylio (polygami) - Carico (sitchensis) - Spiraeo (douglasii) - Myricetum galis developing along the shore of the lake. (Drum Lakes, VII U, 1968) Figure ko. Campylio (polygami) - Carico (sitchenis) -Spiraeo (douglasii) - Myricetum galis occurs along the lake shore where parent material consists of a mixture of beach gravel and drifted organic debris. No trees grow in the association because of i t s peculiar habitat conditions, except for a few small individu-als of Alnus rubra. (Plot 9 4 , VII 1 2 , 1 9 7 0 ) 145 ation of water level. Horizon differentiation, therefore, is not apparent. Texture is generally coarse as most of the samples were determined to be loamy sand or sand. Content of organic matter i s highly variable from trace(0.2%) up to k"J% of the organic horizon, depending upon how much organic debris has been deposited by chance. The pH value ranges from 4.9 to 5.7 with an average of 5.3. Cation exchange capacity averages 21.4 m.eq./lOO g of s o i l , ranging from 2.9 to 73.7 m.eq./lOO g of s o i l . This extreme v a r i a b i l i t y is a result of heterogeneity of the s o i l conditions. Other chemical characters are also very variable, since the soils are so heterogeneous. General characteristics of soils are shown in Table 31. In this association, soils were classified as Gleyed Regosols. 1 U 6 VI. Vegetation and Environment Relationships 1 . Topographic sequence of the association The topographic sequence of the associations is shown in Figure kl and U 2 . This sequence i s coincidentally identical with the hygrotopic sequence of the association, since the hygrotope is dependent, to a great extent, upon topographic situation and s o i l texture. S o i l texture is almost homogeneous throughout the study area. Some differences in vegetation are recognized between the drier subzone (under humid climate) and the wetter subzone (under perhumid climate). i . The drier subzone (CWHa): On the ultraxeric habitats on ridge and exposed rock outcrops, where soils are extremely dry and shallow, the Juniperus communis var. montana association develops. It is especially common on south facing rocky c l i f f s . The habitats are so dry and soils are so shallow that no trees practically exist in this association except for very few stunted individuals of Pinus contorta and Pseudotsuga menziesii. Although this association i s found mainly in the drier subzone, i t may occur in the wetter subzone, provided that warm and dry habitats are available on south facing slopes. The second association which occurs on xeric habitats is Gaultheria  shallon association. Again i t develops on relatively shallow s o i l s , but soils in this association must be deep enough to support tree growth, since i t is one of the forested associations. It also tends to appear commonly on south facing and rather steep slopes, though these are not essential conditions. As the soils become deeper and moisture content increases, the Gaultheria  shallon association is gradually replaced by the moss association. The moss association develops on gentle slopes with deep and moderately A M (h ) * T * Pseudotsuga menziesii j^Tsuga heterophylla ^Thu.ja plicata Ultra O - A Xeric Xer i c Mesic Hygr ic ; Hjrd J« the Junlperus communis var. montana association G: the Gaultheria shallon association M(m). the moss association. Mahonia nervosa variant M(h)» the moss association. Hylocomium splendens variant A-P(a)i the Achlys - Polystichum association. Achlys triphylla variant A-P(p)i the Achlys - Polystichum association. Polystichum munitum variant O-At the Oplopanax - Adiantum association A - P ( a } A - P(P) Figure 41. Topographic sequence of associations under humid climate Abies amabilis A - P ( g ) Xer ic Mes ic Hyg ric G: the Gaultheria shallon association M: the moss association V: the Vaccinium alaskaense association Ly: the Lysichitum americanum association A-P(g): the Achlys - Polystichum association. Gymnocarplum dryopteris 0-A: the Oplopanax - Adiantum association O - A •tr co Figure k2. Topographic sequence of the associations under perhumid climate 149 moistened s o i l s , and the hygrotope is rated as mesic. On such mesic habitats, precipitation is considered to be the only source of water supply to the sites (Orloci 1964), since no seepage water is present at least during the summer dry season. In this association two variants (mahoniosum nervosae and hylocomiosum splendentis) are recognized. The former variant tends to occur on comparatively drier habitats between the Gaultheria shallon association and the other variant hylocomiosum splendentis, and the latter variant occupies comparatively wetter sites which are estimated as mesic and topographically lower. The fourth association is the Achlys - Polystichum association which develops on subhygric to hygric habitats on gentle slopes of the mountain base, close to the bottom of valleys. Two variants (achlydosum triphyllae and polystichosum muniti) are recognized, of which the achlydosum triphyllae develops on comparatively drier habitats such as undulating slopes where parent material consists of glacial residues, or small a l l u v i a l fans where parent material is coarse a l l u v i a l deposits, whereas the other variant polystichosum muniti occurs on concave topography where seepage water (tempo-rary or permanent) is available. Thus, the sequence of the variants is found where the former is comparatively higher and the latter lower. At the bottom of valleys or along streams, the Oplopanax - Adiantum association develops. The habitats are so saturated with water a l l the time that the hygrotope is rated as hydric. i i . The wetter subzone (CWHb): The wetter subzone is substantiated by the high amount of annual total precipitation which exceeds 2800 mm. Under the particular climatic conditions, the response and the character of the vegetation as well as soils are so different that the kinds and sequence of the 150 associations along the topographic gradient are also different from that of the drier subzone. In the wetter subzone, which includes the Elk River Valley, Heber River Valley, upper part of Wolf River Valley and Cervus Creek, on xeric habitats the Gaultheria shallon association develops again, which is more or less identical to that of the drier subzone. On mesic habitats below the Gaultheria shallon association, the moss association occurs on subxeric to mesic habitats, although i t is not so extensive as in the drier subzone. The Vaccinium alaskaense association occupies extensive areas in the wetter subzone, covering mesic to drier parts of subhygric habitats. Topographically, i t occurs on undulating gentle slopes on the h i l l s i d e and occasionally close to the bottom of the valleys. F l o r i s t i c a l l y , i t is characterized by the presence of Abies amabilis, Vaccimium  alaskaense. Rubus pedatus, Streptopus roseus and Streptopus streptopoides a l l of which are actually missing in the drier subzone. The Lysichitum americanum association is found occasionally sur-rounded by the Vaccinium alaskaese association. It occurs on small "watch-glass" like depressions where water stagnates and thick amorphously decomposed organic matter (black muck) is accumulated. Thus, the occurrence of this association is quite dependent upon local topographical situation. This association almost lacks a tree layer due to the very particular habitat conditions. The hygrotope of the association is rated as hydric. At the base of the h i l l s i d e , where the hygrotope is rated as sub-hygric to hygric, the Achlys - Polystichum association, especially a particular variant gymnocarpiosum dryopteridis occurs on gentle slopes. Soils 151 are f a i r l y fine and they contain relatively high amounts of s i l t . In general the water table is relatively high; in some cases i t is found at a depth of 80 - 100 cm below ground surface. Soils are mostly Gleysols. At the bottom of the valleys and along streams, the Oplopanax  Adiantum association develops again the same as in the drier subzone. The Myrica ffale association is formed on lake shores where organic debris drif t s and accumulate. 2. Relationships between associations and environmental factors In the previous chapter, eight associations were established and discussed f u l l y . Three of them are non-forested associations (the Juniperus  communis var. montana association, the Lysichitum americanum association and the Myrica gale association) with the remainder being forested associations. The causality of the non-forested associations is relatively easily under-standable, because they develop under rather extreme habitat conditions. For the forested association,however, more elaborate considerations are necessary, since their habitat segregation and differentiation are somewhat more subtle than in the non-forested associations. In this chapter, the relationships between five forested associations and environmental factors are dealt with more thoroughly. For this purpose, s t a t i s t i c a l approaches are f u l l y employed. A l l environmental factors which were quantitatively measurable were taken into consideration. Actually, twenty-two factors were s t a t i s t i c a l l y processed (Table 32). For convenience, in this chapter, five associatinns are symbolized as follows, G: the Gaultheria 152 Table 32. Environmental factors taken into the s t a t i s t i c a l treatments Variable Factor No. Symbol Unit Grand mean (n=78) Min. Max. SD* XI Light intensity X2 pH of humus X3 pH of the C horizon Field moisture Field capacity Sand S i l t Clay Xk X5 X6 X7 X8 X9 Cation exchange capacity of humus X10 Cation exchange capacity of mineral soils X l l Calcium content X12 Magnesium content X13 Sodium content Xlk Potassium content XI5 Total amount of organic matter Xl6 Total amount of nitrogen X17 Total amount of available phosphorus Xl8 Slope X19 C/N ratio of humus X20 C/N ratio of mineral soils X21 Base saturation of humus X22 Base saturation of mineral soils LIGHT lux 1972 677 5051 928 PH-H k . 9 3 .6 l . k 0 .76 PH-C 5 . 8 k . 6 6 . 9 0.1+8 FM % volume 22.5 5.9 96.7 11+.5 FC % volume 25.2 9.0 37.0 6.3 SAND % 81+.3 6 6 . 6 91+.9 5.3 SILT % 12 .8 3.2 29.2 5.1 CLAY rf 10 2 . 8 0.0 9.0 2.0 CEC-H m.eq. /100g 100.0 20.1+ 173.0 36.2 CEC-M m.eq./lOOg 18.5 5.7 1+1+.1+ 8 . 6 CA eq./cub.m. 2 5 . 9 3.3 129.1 26.1 Mg eq. /cub.m. k . 6 1.0 33 .8 1+.5 NA eq./cub.m. 1 .5 0 .5 1+.0 0.7 K eq./cub.m. 0 .7 0.2 2 .5 0 .3 OM kg/cub.m. 30.3 9 . k 5 9 . 6 11.1 N g/cub.m. 586 196 1680 253 P g/cub.m. 1 .9 0.1 5.7 1.2 SLOPE degree 11.7 0.0 33.0 9 . 8 C/N-H 3 6 . 6 12 .8 9 5 . 7 15.3 C/N-M 3U.2 13.3 79. k 15.0 BS-H of 29 .8 10.0 7 6 . 8 15.7 BS-M % 30.7 3.0 89.I 20.9 * Standard deviation 153 shallon association; M: the moss association; A-P: the Achlvs - Polystichum association; V: the Vaccinium alaskaense association; 0-A: the Q-plopanax - Adiantum association. Recently, many workers in various parts of the world have made many attempts to introduce quantitative or s t a t i s t i c a l approaches into the f i e l d of plant ecology (see Greig-Smith 1957, Lambert and Dale 196k, Pielou 1969, Goodall 1970). According to Goodall (1970) , the major function of s t a t i s t i c a l techniques is three-fold: l ) reducing a complex mass of data to a simple form, i.e. building up a model, 2) estimation and determination of parameters which define the model, and 3) test of hypothesis, casting i t into a testable form. When s t a t i s t i c a l techniques are employed, particular caution is necessary, because some sets of data may not satisfy the basic assumptions for s t a t i s t i c a l treatments, and a consequence of this may be an invalidation of the procedures. For instance, a heterogeneity of variances of measurements are a relatively common feature in the biological f i e l d , which thus requires certain transformation of raw data. Although a s t a t i s t i c a l technique, especially by introducing an electronic computer, is very useful to process a large amount of data which are expressed quantitatively, i t is not very effective in handling qualitative aspects which may be very important to a certain phenomenon. This chapter is divided conveniently into two parts (part A and part B), In the f i r s t part, the relationships between environmental factors and the associations are discussed analytically based on the results of 15U analysis of variance. In addition, the response of the associations to respective environmental factors and a sequence of the associations along the gradients of respective factors are also discussed. In the second part, the overall relationships between an association and the environmental factors are described integratingly, using a multiple regression analysis method, and the most influential factor(s) to respective association are selected and described. Prior to carry out the analysis of variance and sub-sequent multiple regression analysis, a correlation matrix for a l l possible pairs of the twenty-two factors was constructed in order to take a general view of relationships among the factors. The matrix is shown in Table 33. A. Sequence and responses of the associations to the environmental factors In this part, the relationships between the associations and the environmental factors are discussed. In order to analyse the relation-ships, analysis of variance was used. Analysis of variance, which was devised and developed by Fisher (195M, is a very powerful method to test whether the samples are from the same population or not, where the n u l l hypothesis is that a number of means of groups are equal, i.e. jx^ = jig* =u.n. Technically, i t is an arithmetic device for partitioning the total variation in a set of data according to the various sources of variation that are present. To carry out the analysis of variance, in this study, each measurement of a factor is regarded as an observation, and the observations are grouped into five lots which are equivalent to the associations. As the associations are comprised of different numbers of plots, this is the case of the one way analysis of variance with an unequal number of obser-C O R R E L A T I O N M A T R I X Table 33 R O W X I L I G H T 1 . G O O O O R O W X 2 Pl -MH) - 0 . 0 3 5 3 2 1 . 0 0 0 0 0 R O W X 3 P H ( C ) - 0 . 2 0 4 9 5 0 . 7 1 5 9 2 1 . 0 0 0 0 0 R O W X 4 F M 0 . 1 5 2 1 0 0 . 3 1 5 4 2 0 . 2 2 1 4 1 1 . 0 0 0 0 0 R O W X 5 FC 0 . 1 8 5 4 2 0 . 0 3 9 6 2 - 0 . 0 6 9 9 8 0 , 3 6 4 3 8 1 . 0 0 0 0 0 R O W X 6 SAND - 0 . 0 6 2 7 1 0 . 0 9 9 2 0 0 . 2 3 3 6 9 0 . 0 8 6 6 3 - 0 . 5 2 3 6 6 1 . 0 0 0 0 0 R O W X 7 S I L T - 0 . 0 0 6 4 1 0 . 0 3 2 8 0 - 0 . 1 4 7 9 2 0 . 0 3 0 1 6 0 . 5 7 8 7 2 - 0 . 9 2 8 0 7 1 . 0 0 0 0 0 R O W X 8 CLAY 0 . 1 8 9 0 6 - 0 . 3 4 8 9 1 - 0 . 2 4 3 0 3 - 0 . 3 0 1 0 4 - 0 . 0 7 4 7 8 - 0 . 2 9 5 2 8 - 0 . 0 8 1 2 7 1 . 0 0 0 0 0 R O W X 9 C E C - H 0 . 1 0 7 6 2 - 0 . 2 1 5 1 5 - 0 . 0 2 7 3 0 0 . 0 2 2 2 3 - 0 . 1 3 4 . 1 0 0 . 2 5 9 8 2 - 0 . 2 6 9 4 2 - 0 . 0 0 5 0 3 1 . 0 0 0 0 0 R O W X 1 0 C E C - M 0 . 0 5 5 2 0 0 . 3 3 3 0 0 0 . 3 2 1 2 9 0 . 5 8 0 6 1 0 . 3 8 9 5 9 - 0 - 0 2 5 6 5 0 . 1 0 4 0 8 - 0 - 1 8 8 0 5 0 . 0 8 3 2 4 1 . 0 0 0 0 0 R O W X l l C A - 0 . 1 1 1 4 1 0 . 7 1 0 9 6 0 . 6 9 8 6 7 0 . 5 2 9 4 2 0 . 0 0 6 2 6 0 . 1 9 3 2 7 - 0 . 0 5 9 9 7 - 0 . 3 6 2 5 5 0 . 0 4 5 5 9 0 . 5 4 4 6 7 1 . 0 0 0 0 0 R O W X 1 2 M G - 0 . 1 2 4 5 3 0 . 4 9 8 1 9 0 . 5 2 0 8 5 0 . 5 1 7 3 6 0 . 0 6 4 0 7 0 . 0 7 1 9 3 0 . 0 2 7 7 1 - 0 . 2 5 9 8 0 0 . 0 8 5 5 4 0 . 5 0 9 5 5 0 . 8 3 1 6 7 1 . 0 0 0 0 0 R O W X 1 3 NA - 0 . 2 3 9 4 8 - 0 . 0 5 0 1 4 - 0 . 1 6 9 0 9 - 0 . 0 1 2 6 2 - 0 . 2 2 4 3 4 0 . 0 4 0 2 0 0 - 0 2 0 4 7 - 0 . 1 6 9 1 9 - 0 - 1 9 5 4 4 - 0 . 2 4 9 7 8 0 . 0 0 5 4 5 0 . 0 5 7 1 5 1 . 0 0 0 0 0 R O W X 1 4 K 0 . 0 9 8 0 4 - 0 . 4 0 2 9 6 - 0 . 4 2 0 2 5 - 0 . 1 8 0 1 7 - 0 . 0 2 6 5 9 - 0 . 1 8 0 1 3 0 . 1 1 7 4 8 0 . 1 7 9 1 2 0 . 1 9 1 0 5 - 0 . 2 0 6 5 3 - 0 . 2 7 6 1 9 - 0 . 1 3 2 7 0 0 . 0 1 0 6 3 1 . 0 0 0 0 0 R O W X 1 5 O M 0 . 1 6 3 7 3 0 . 0 5 6 7 4 - 0 . 0 5 3 7 3 0 . 4 2 7 1 2 0 . 2 4 4 6 2 - 0 . 2 1 2 9 9 0 . 3 4 3 3 3 - 0 . 3 1 7 2 5 0 . 0 8 9 7 0 0 . 3 6 5 5 4 0 . 3 0 2 6 7 0 - 2 8 8 6 5 0 . 0 8 1 . 0 1 0 . 0 6 9 0 9 1 . 0 0 0 0 0 R O W X 1 6 N 0 . 0 8 5 2 4 ' 0 . 1 7 1 9 1 0 . 0 9 4 1 0 0 . 6 5 5 9 3 0 . 2 7 6 5 6 0 . 0 4 8 2 2 0 - L 2 1 3 5 - 0 . 4 3 9 2 8 0 . 1 2 1 6 7 0 . 5 2 0 4 0 0 . 4 5 3 0 3 0 . 3 9 6 9 4 0 . 1 0 3 9 5 - 0 . 0 7 8 5 5 0 . 6 5 8 8 5 1 . 0 0 0 0 0 R O W X 1 7 P - 0 . 2 3 1 3 6 - 0 . 0 6 0 2 4 - 0 . 0 1 8 5 1 - 0 . 1 7 1 0 5 0 . 0 7 9 0 2 - 0 . 0 6 9 5 4 0 . 1 0 6 8 8 - 0 . 0 8 8 7 8 - 0 . 0 3 2 5 7 0 . 0 5 6 0 1 - 0 . 0 4 4 5 2 - 0 . 0 5 7 4 4 - 0 . 1 4 9 6 1 0 . 2 7 6 6 6 0 . 0 5 0 4 1 0 . 0 4 6 4 9 1 . 0 0 0 0 0 R O W X 1 8 S L O P E 0 . 1 6 6 9 5 - 0 . 0 0 5 9 0 - 0 . 0 2 8 3 3 0 . 0 8 3 6 8 0 . 2 2 3 2 8 0 . 0 4 2 8 0 - 0 - 0 9 2 8 0 0 . 1 3 0 2 1 - 0 . 0 5 8 5 9 0 . 2 4 9 1 6 - 0 . 0 9 2 0 1 0 - 0 0 4 5 9 - 0 . 2 0 1 9 0 - 0 . 0 4 5 4 3 - 0 . 0 6 8 1 7 0 . 0 8 6 5 3 0 . 0 2 8 3 3 1 . 0 0 0 0 0 R O W X 1 9 C / N - H 0 . 1 6 5 0 1 - 0 . 0 0 5 0 9 - 0 . 1 4 4 7 8 0 . 0 2 8 7 0 0 . 0 1 3 0 3 - 0 . 0 5 5 1 7 0 . 0 7 7 5 8 - 0 . 0 5 6 1 1 0 . 0 4 8 4 7 - 0 . 0 8 3 1 9 - 0 . 0 6 5 3 8 - 0 . 1 1 1 0 6 0 . 0 4 6 8 3 0 . 0 9 9 6 9 0 . 2 3 5 0 6 - 0 . 1 6 4 6 7 - 0 - 1 6 9 8 2 - 0 . 1 5 7 6 1 1 . 0 0 0 0 0 R O W X 2 0 C/H-H 0 . 3 1 0 3 0 - 0 . 2 0 0 2 4 - 0 - 2 5 9 1 6 - 0 . 2 2 1 8 7 0 . 0 9 3 7 6 - 0 . 2 2 6 5 8 0 . 1 6 7 3 7 0 . 1 7 6 2 2 - 0 . 1 1 7 3 3 - 0 . 1 8 9 0 5 - 0 . 3 0 8 0 7 - 0 . 3 0 3 5 2 - 0 . 0 8 3 5 9 0 . 0 4 4 4 1 0 . 1 4 2 8 3 - 0 . 4 3 0 5 4 - 0 . 1 2 0 9 5 - 0 . 0 2 4 7 7 0 . 2 3 4 5 1 1 . 0 0 0 0 0 R O W X 2 1 8 S - H - 0 . 0 9 6 2 2 0 . 6 8 2 0 8 0 - 5 7 7 8 4 0 . 2 8 4 0 3 0 - 1 0 5 6 3 - 0 . 0 1 2 6 8 0 . 0 7 7 1 1 - 0 . 1 5 8 6 0 - 0 - 3 8 1 7 1 . 0 . 3 5 8 5 3 0 . 5 8 3 8 7 0 . 4 6 2 3 5 - 0 - 1 3 4 8 1 - 0 . 2 9 8 3 5 - 0 . 0 8 3 7 9 0 . 1 2 3 4 6 0 . 0 5 9 3 5 0 . 0 2 2 1 4 - 0 . 3 1 7 7 3 - 0 . 1 5 2 2 0 1 . 0 0 0 0 0 R O W X 2 2 B S - M - 0 . 1 8 1 8 7 0 . 5 3 3 8 1 0 - 6 3 2 8 1 0 . 1 6 7 1 5 - 0 . 3 2 5 5 1 0 . 4 0 5 8 4 - 0 . 2 9 6 6 9 - 0 . 3 2 4 1 5 0 . 0 9 8 0 2 0 . 1 1 2 8 7 0 . 6 8 4 5 8 0 . 4 2 6 2 6 0 . 0 1 4 1 4 - 0 . 1 8 5 8 5 - 0 . 0 0 9 6 6 0 . 2 5 3 5 7 0 . 1 0 6 5 4 - 0 . 1 2 3 7 0 - 0 . 0 9 6 7 5 - 0 . 4 3 3 4 8 0 . 4 3 3 0 0 1 . 0 0 0 0 0 J 156 vations. Numbers of observations of each associations are as follows: Gaultheria  shallon association 11; the moss association 23; the Achlys - Polystichum as-sociation 23; the Oplopanax - Adiantum association 10; the Vaccinium alaskaense association 12. In some cases numbers of observations may be different when some values are missing. Transformation of raw data was done to some factors so that the variances were homogeneous. The following analysis of variance table was, thus, constructed. Source of variation Degree of freedom Between associations U Within associations Jk Total 78 The result of the analysis of variance i s shown in Appendix V. Although analysis of variance is a very useful tool to test whether the means are significantly different from each other, i t cannot detect which mean(s) is actually different from others. Duncan's new multiple range test is a device to complement the disadvantage of the analysis of variance, and i t is employed to rank the means after they become known. Thus, Duncan's new multiple range test was carried out on the factors which were found to be significantly different either at the 5% level of 1% level in the analysis of variance. Scheffe's test for multiple comparison was also consulted to group the associations. In this study, after the associations were grouped and ranked by Duncan's new multiple range test, they were arranged diagramatically in 157 a declining order of their mean values from the l e f t to the right. The grouping of associations are shown by an underline so that the same underline connects the associations which belong to the same group at the 5% level (a single line) or 1% level (a double l i n e ) . When a l l the associations are not significantly different from each other, they are underlined with a dotted line, l ) Light intensity; Light intensity is defined, here, as the amount of light which i s received under the forest canopy at a height of 1 m above the ground surface. This amount of light has a very significant effect on most of the plants which grow within the forest, since they are obliged to u t i l i z e the amount of available light effectively to sustain their l i v e s , and failure to do so would result in an immediate elimination of the taxa from the site. Thus, light intensity would act as a limiting factor for some species, and consequently i t determines the kinds of vegetation, to a certain marked degree. Generally light intensity shows an inverse relation to the crown closure of the forest. In fact, the Gaultheria shallon association, which has the lowest coverage of the A layer, shows the highest light intensity among the associations, while the Achlys - Polystichum association, in which the coverage of the A layer i s the highest, shows the lowest light intensity. The analysis of variance indicates that there i s a significant difference among the associations regarding light intensity with the value of F = 9.71 which is highly significant at the 1% level, after the logarithmic 158 transformation of the raw data. Duncan's new multiple range test shows the relations among the associations as follows: G 0-A V M A-P 3239 2188 1943 1750 1489 There is no significant correlation recognized between light intensity and other factors. 2) pH of humus: The pH of humus is also an important factor which could control the kind and development of vegetation. Since humus is the f i r s t medium which a l l plants growing in the forest must encounter immediately when they germinate. Only the plants which can adapt to the particular conditions can survive and contribute to the fl o r a of the communities. However, at the same time, the humus i t s e l f i s also influenced by various environmental factors, since i t i s also a part of the complex ecosystem. Thus, pH of humus is regarded as a product and tot a l expression of ecosystematic interactions. Generally, the type of humus is particularly controlled by the climatic conditions and the kind of vegetation. Under a humid and cool climate, where fung a l activity is predominant and humus is formed of imperfectly decomposed,thick accumulations of organic debris, the pH value 159 tends to be low. When the humus consists prevailingly of conifer l i t t e r which contains a lower amount of calcium, and other cations, the pH value again would be low (Lutz and Chandler 19*+6). The analysis of variance indicates that a significant difference of the pH value exists among the associations with the value of F = 21.32 which is highly significant at the 1% level. Duncan's new multiple range test shows the following relations among the associations: 0-A A-P G M V 6.2 U.9 k.8 h.6 k.2 The difference of the pH values of the humus among the associ-ations is probably due primarily to the effectiveness of the seepage water, and secondarily, to the degree of addition of basic cations to the humus through the biogeochemical cycling processes, especially the vegetation. These two are more or less correlated with each other. For instance, the Oplopanax - Adiantum association, in which the habitats are constantly saturated with seepage water, shows a high pH value of humus as a result of the neutalization by the basic cations which have been brought by the seep-age. Under such circumstances particular plants thrive that require a f a i r l y high amount of cations, especially of calcium, and consequently their leaves contain relatively high amounts of these cations. This causes a high base cycling which would result in the maintenance of habitats rich in I 1 6 0 I Horizon k.O 5 . . 0 6.0 \ \i \ \ \ \ \ lift fifc V \ • \ * v• * V\ * \ *. * « \\\ > ® 9 the Gaultheria shallon association 9 -6 the moss association & O the Vaccinium alaskaense association $ ~ — © the Achlys - Polystichum association @ © the Oplopanax - Adiantum association Figure 43, S o i l reactions (pH) of different horizons in the associations. l 6 i cations for a long period and less acidity of the so i l s . On the other hand, on habitats where a seepage effect is actually absent, the situation is very different. A rapid s o i l depauperation would take place as a result of loss of cations from the habitats, and a result of this would be a formation of strongly acidic humus as well as mineral s o i l s . In this study, pH value of humus is strongly correlated with that of the C horizon (r* - 0.72), the amount of calcium (r = 0.71), base saturation of humus (r = 0.68) as well as mineral soils (r = 0.53), and the amount of magnesium (r = 0.50). Since pH value is dependent upon the proportion of hydrogen ions and other basic cations, i t is understandable that i t has a high correlation with amount of these cations and the conse-quent base saturation. There i s a slight tendency toward positive corre-lation between the pH value of humus and f i e l d moisture (r = 0.32) which indicates that seepage effect would cause pH values to increase, supplying a high amount of cations. 3) pH of the C horizon: The pH value of the C horizon was measured. The C horizon is a mineral horizon which underlies the B horizon and i t is less affected by the s o i l forming processes. Gleyzation and the accumu-lation of carbonates and salt (under an arid climate) are the conspicuous features of the horizon. Generally the pH value of the C horizon i s higher than that of the overlying horizions due to the higher concentration of basic cations. r: simple correlation coefficient 162 Although the difference of the pH values of the C horizon i s not so great among the associations as that of the humus, a considerable difference is recognized as the analysis of variance indicates, with the value of F = 9 . 2 0 which is highly significant at the 1% level. Duncan's new multiple range test show the relation among the associations as follows: 0-A A-P G M V 6 . 5 5 . 9 5.T 5.T 5 . 6 The pH value of the C horizon seems to be highly dependent upon the amount of cations such as calcium and magnesium, because strong cor-relations were recognized between the calcium content (r = 0 . 7 0 ) and magnesium content (r = 0 . 5 2 ) , and also with consequent base saturation of mineral soils (r = 0 . 6 3 ) as well as that of humus (r - 0 . 5 8 ) . This is probably due to the neutralizing effect of the cations which give the increase of the pH values. Moreover, since these cations are mostly transported and supplied by seepage, the habitats where seepage effect is present tend to show relatively high pH values. Indeed, the Gaultheria shallon association, the moss association and the Vaccinium alaskaense association, where seepage effects are practically n i l , show comparatively low pH values, whereas the Oplopanax - Adiantum association, in which the habitats are constantly affected by seepage, shows the highest pH values among the associations, the Achlys - Polystichum association in which seepage is present shows the 163 second highest pH values of the C horizon. As is shown in Figure 1+3, the pH of the A horizon is generally higher than that of the humus, hut the sequence of the associations is a l -most the same as the case of the humus. The pH of the B horizon, on the other hand, becomes much higher than that of the humus and the relations among the associations show a similar tendency to that of the C horizon. The Oplopanax - Adiantum association shows remarkably high pH values throughout the horizons, reflecting the high base status resulted from the permanent seepage effect. k) Field moisture; Field moisture is the content of water in a s o i l under f i e l d conditions. It is very variable depending upon the situation, e.g. s o i l texture, season of the year, weather conditions, topography, presence or absence of seepage, kind of vegetation and i t s coverage, and so on. As the f i e l d moisture i s one of the factors most influential upon the development and differentiation of vegetation, i t must be considered carefully. From each s o i l p i t in a plot, usually three samples were collected principally in July, and the collection was not done for at least two days after a rain. In the study area, July is the driest month of the year, and during most of the month extreme f i r e hazard warnings are issued. Thus, a l l of the samples were presumed to have been gravitationally drained completely in regard to excess water, and the water contained in the samples was regarded as dependent upon the water retention capacity of the soils plus a certain amount of water supplied by seepage. Therefore, 16k i f the seepage effect was n i l , the samples would be drier than, or equal to, their f i e l d capacity which was-measured separately in the laboratory. In other words, the f i e l d moisture could be indicative of the amount of seepage water available to the s i t e , assuming that the water retention capacity i s more or less the same throughout the samples. S o i l texture i s the greatest contributor to the water retention capacity of a s o i l . It i s relatively homogeneous throughout the study area, as most of the soils are loamy sand with some being sand and sandy loam. Seepage is a major source not only of water but also of nutrients, especially various kinds of cations, therefore, the amount of f i e l d moisture usually tends to show strong correlations with some other factors such as calcium content, magnesium content, the t o t a l amount of organic matter and nitrogen. In this study, f i e l d moisture is expressed in percentage of water to the s o i l on the volume basis, and i t is a weighted average of three hori-zons. Analysis of variance indicates that there is a significant difference among associations in respect to f i e l d moisture with the value of F = 8.87 which is highly significant at the 1% level. Duncan's new multiple range test shows the relations among the associations as follow j 0-A V A-P M G kk.1 23.5 22.3 15.9 15.7 165 This sequence of the associations is almost the same as the topographic and hygrotopic sequences which were discussed in an earlier section, since the f i e l d moisture is indicative of the seepage effect to the habitats. Field moisture, in this study, is strongly correlated with nitrogen content (r = 0 . 6 6 ) , cation exchange capacity of mineral soils (r = 0 . 5 8 ) , calcium content (r = 0 . 5 3 ) , magnesium content (r = 0 . 5 2 ) , and the amount of organic matter (r = 0.1+3). Since most of the basic cations are transported by seepage water and supplied to the habitats, i t is under-standable that there is a high correlation between cations and f i e l d moisture. Cation exchange capacity of mineral s o i l s , which shows high correlation with f i e l d moisture, seems to be rather dependent upon the amount of organic matter, since organic matter is an exerting contributor to the cation exchange capacity. Thus, the correlation is regarded rather as an indirect correlation. The correlation between f i e l d moisture and the nitrogen content, and organic matter are discussed in the appropriate sections. 5) Field capacity: Field capacity is defined as the amount of water held in the s o i l after the excess gravitational water has drained away and after the rate of downward movement of water has materially decreased (Veihmeyer and Hendrickson 1 9 3 1 ) , It is highly dependent upon s o i l texture and content of organic matter (Lutz and Chandler 1 9 4 6 ). The water content at 1/3 atmos-pheric pressure, which is measured in the laboratory, is used for an approx-imate estimation of the f i e l d capacity (Peters 1 9 6 5 ), since the close correlation between the two values has been recognized in most s o i l s . < 166 In this study, most of the soils are so coarse and more or less homogeneous in s o i l texture that the f i e l d capacity was found to be rather low and there is no significant difference depending upon the kind of vegetation, in contrast to the f i e l d moisture discussed in the previous section. Field capacity is expressed in percentage on a volume basis. The same as the case of f i e l d moisture, values are the weighed average of three horizons. Analysis of variance indicates that no significant difference exists among the associations with the value of F = 0 . 5 2 . 0-A G M V A-P 2 6 . 8 2 6 . 4 2 5 . 0 24 .7 2 3 . 8 F i e l d capacity is correlated positively with s i l t content (r = 0 . 5 8 ) and correlated negatively with sand content (r = - 0 . 5 2 ) . Since f i e l d capacity is dependent upon s o i l texture and generally the finer the s o i l tex-ture becomes the greater the amount of water that is retained in the s o i l s , these positive and negative correlations with different particle size are understandable. No practical correlation was recognized between f i e l d capacity and clay content. This is probably due to too small amount of clay in the soils to contribute significantly to the f i e l d capacity, as the mean of clay content is only 2.6% throughout the samples. The relation between f i e l d capacity and f i e l d moisture is described in terms of a simple regression analysis. On the X-Y co-ordination, where X is designated to f i e l d capacity and Y to f i e l d moisture, the relationships between X and Y are explained by the following regression equations obtained respectively for each 167 association: (1) the Gaultheria shallon association Y = 8.917 + 0.2621X with r = 0.21 and F = 1.30 N.S. (2) the moss association Y = 8.545 + 0.2933X with r • 0.47 and F = 5.82* (3) the Vaccinium alaskaense association Y = 11.320 + 0.4858X with r = 0.44 and F = 7.96** (4) the Achlys - Polystichum association Y • -4.395 + 1.0972X with r =0.73 and F =22.20** (5) the Oplopanax - Adiantum association Y = -2.796 + 1.7250X with r = 0.44 and F = 7.96** N.S. non significant * significant at the 5% level ** significant at the 1% level These equations are graphically presented in Figure 44, There is a noticeable feature that the slopes of the equations become steeper with associations from the Gaultheria shallon association to the Oplopanax -Adiantum association, which exactly corresponds to the hygrotope of the associations. Thus, the simple regression equation, especially i t s regression coefficient, between f i e l d capacity and f i e l d moisture may be used as an indicator of hygrotope, provided that a l l samples for determination of f i e l d moisture are free from rain water at least for two days so that they are com-pletely drained of excess water, and water content in the samples is only dependent upon seepage effect. l O O & r 0-A 10 20' 3^ " Y=8.92 + 0.26X M 10 20 30 Y-8.54 + 0.29X 10 20 30 Y-11.3 + 0.49X 10 20 30 40 Y—4.39 + 1.10X 10 20 30# Y«-2.80 + 1.73X Figure kk. Regression lines between field capacity 00 and field moisture (Y) for the associations. Lines are drawn within the ranges of actual measurements. ON co 169 6) Sand: So i l texture is one of the major physical properties of s o i l . It controls not only water-holding capacity hut also f e r t i l i t y of the s o i l . It also is involved with s o i l structure and consistency to a certain degree. S o i l texture is determined by a relative proportion of particles of different sizes. Sand is made up of particles of which the size l i e s between 0.05 and 2.0 mm. Though sand is chemically almost inert because of i t s com-paratively small specific surface, i t is an important component of s o i l s , which serves as a skeleton giving the soils not only the framework but also considerable pore spaces where finer particles including colloids are settled, water moves and in which air diffuses improving aeration of the soils and consequently stimulating microbial activity. It also contributes greatly to drainage of water. Nevertheless, sand does not function much as a nutrient reservoir, because of i t s very low cation exchange capacity. Sandy s o i l s , therefore, have generally low water retention capacity as well as f e r t i l i t y , since water and mineral nutrients are held principally by s o i l colloids. Sandy soils are highly advantageous for root penetration, thus the root system can get easily established on sandy s o i l s . Throughout the study area, soils are generally coarse as most of the soils were determined as sand with some being sand or loamy sand. Thus, sand is a factor that cannot be neglected in this study. Analysis of variance, however, indicates that there is no significant difference among the associa-tions in respect to the content of sand with the value of F = 0.76. 0-A V G M A-P 87.0 84. k 84.0 84.0 83.6 170 The content o f sand i n the s tudy area i s n e g a t i v e l y c o r r e l a t e d w i t h the content o f s i l t ( r = - 0 . 9 3 ) and f i e l d c a p a c i t y ( r = - 0 . 5 2 ) . The n e g a t i v e c o r r e l a t i o n "between sand and s i l t i s o b v i o u s , s i n c e the p a r t i c l e s i z e c l a s s e s are expressed i n percentage so t h a t t o t a l o f them i s 1 0 0 $ . The n e g a t i v e c o r r e l a t i o n w i t h f i e l d c a p a c i t y i s a l s o q u i t e u n d e r s t a n d a b l e , s i n c e sand has a v e r y l o w water h o l d i n g c a p a c i t y . 7) S i l t : S i l t i s made up o f s o i l p a r t i c l e s i n which s i z e ranges from 0 . 0 0 2 t o 0 . 0 5 mm. I t s p h y s i c a l and che mi c a l c h a r a c t e r s are somewhat i n t e r m e d i a t e between sand and c l a y . Water h o l d i n g c a p a c i t y o f s i l t i s h i g h e r than t h a t o f s a n d , but lower than t h a t o f c l a y . I t i s known, however, t h a t a v a i l a b l e water c a p a c i t y f o r p l a n t s i n c r e a s e s w i t h the amount of s i l t , because s i l t y s o i l s can h o l d the g r e a t e s t amount o f c a p i l l a r y water which i s r e a d i l y a v a i l a b l e by p l a n t s ( M i l l e r _ e t a l . 1 9 6 6 ) . Daubenmire (1947) suggested t h a t a t o t a l percentage o f s i l t and c l a y i n a s o i l was e c o l o g i c a l l y more s i g n i f i c a n t f o r an e v a l u a t i o n o f h a b i t a t c o n d i t i o n s t h a n r e s p e c t i v e percentages o f s a n d , s i l t and c l a y . Based on t h i s p r o p e r t y , a number of s t u d i e s have been conducted ( K i t t r e d g e 1938» S t o e c k e l e r I 9 6 0 , Pawluk and Arneman 1 9 6 l , and Loucks 1 9 6 2 ) . Brayshaw ( 1 9 5 5 , 1965) p r e s e n t e d a d i s t r i b u t i o n p a t t e r n o f a s s o c i a t i o n s on a two d i m e n s i o n a l c o o r d i n a t i o n ( a l t i t u d e and s o i l t e x t u r e ) and concluded t h a t s o i l t e x t u r e was one o f the major f a c t o r s which d i f f e r e n t i a t e d the Pseudotsuga m e n z i e s i i f o r e s t s , P i n u s ponderosa f o r e s t s and steppe communities i n southern B r i t i s h Columbia . W a l i ( 1 9 6 9 ) demonstrated d i s t r i b u t i o n o f a s s o c i a t i o n s a l o n g a t e x t u r e g r a d i e n t (% s i l t + c l a y ) . B e i l ( 1969) r e c o g n i z e d t h a t s o i l t e x t u r e i s a 171 major factor which differentiated vegetation into forests and grasslands. In this study, analysis of variance does not show any significant difference among the associations with the value of F = 0,6l, in respect to the content of s i l t . This was probably because there was l i t t l e textural variation in the soils studied in the area. V A-P G M 0-A 13.9 13.9 12.5 11.9 11.9 As is discussed earlier, because of i t s high water retention capacity, s i l t contributes very much to f i e l d capacity. Indeed, the content of s i l t is correlated with f i e l d capacity with a correlation coefficient r = 0.58, contrary to the case of sand where the correlation is negative. S i l t i s negatively correlated with sand (r = -0.93) for the same reason as discussed in the previous section. 8) Clay: Clay is made up of particles whose size i s less than 0.002 mm. In temperate regions, i t i s composed chiefly of secondary crystalline aluminosilicates. Most clay particles are colloidal in a s o i l . They highly contribute to the physical and chemical properties of the s o i l . Because of i t s exceedingly large specific surface per unit of mass, clay is the most active part of a mineral s o i l . Ecologically, the most significant roles of clay are l ) to contribute to cation exchange capacity and consequently to preserve mineral nutrients, and 2) to retain a considerable amount of water and to release i t as plants need i t . Thus, clay, in nature, plays the role 172 of a reservoir of nutrients as well as water. Nevertheless, when a s o i l is too rich in clay, the water availability decreases, since the water molecule firmly adheres to the clay particles in the form of hygroscopic water which cannot be absorbed by plants. Clay-rich soils frequently impede root penetration. It is known that, in arid regions, clayey soils frequently act as a factor limiting tree growth due to the lower availability of water and the d i f f i c u l t y of root system establishment (Daubenmire 1942, Brayshaw 1955, 1956, Beil 1969). In the study area in general, clay content is very low as the overall mean is only 2.8$. This is probably because that, the clay content in the parent material was rather poor, and secondarily, the soils are not yet well developed enough to have rich inherited clay accumulation, as most of soils were identified to be Brunisols which are at a rather young stage of s o i l development. However a slight tendency of clay accumulation in the B horizons is observable, especially in relation to the Gaultheria shallon association and the moss association, although i t is not well developed enough to satisfy the condition of a Bt horizonr. Analysis of variance indicates that there is a significant difference among the associations, with respect to the clay content with the value of F = 8.32 which is highly significant at the 1% l e v e l , after the square root transformation of the raw data. Duncan's new multiple range test shows the relation of the associations as follows: M G A-P V 0-A 4.1 3.5 2.4 1.8 1.1 173 This trend of clay content is interpreted as follows: on xeric and mesic habitats where the Gaultheria shallon association and the moss association develop and where seepage effect i s actually non-existent, there is a slight tendency for clay accumulation in the B horizons as a result of downward movement of clay colloids with the percolation of water. However, on hygric and hydric habitats where the Achlys - Polystichum association and the Oplopanax - Adiantum association develop and seepage is one of the characteristics of the habitats, clay colloids transferred from upper layers would be easily washed away by the continuous seepage, or would not be translocated in a permanently wet site. As a result of the elutriation, clay accumulation cannot take place under these circumstances. In the Vaccinium alaskaense association, on the other hand, heavy precipi-tation together with extremely acid* humus would cause the rapid removal of s o i l colloids not only by physical washing out but also by chemical break-ing down of clay particles ("Tonzerfall" j Hartmann 1952). A consequence of this would be also a prevention of the accumulation of clay colloids in the B horizon and a trend toward the development of podzols. Otherwise, there would have been a slight accumulation of clay just as in the moss association, since the association, in general, i s developed on mesic habitats. The content of clay in soils i s negatively correlated with the nitrogen content (r = -0.44). Nitrogen content is positively correlated with f i e l d moisture which has a negative correlation with clay content, since seepage tends to impede the accumulation of clay. Thus, the relation between clay content and nitrogen content would be regarded as an indirect correlation. according to U.S.D.A. Soi l Survey Manual, p. 235 (1951) 9) Cation exchange capacity of humus: Cation exchange capacity i s the t o t a l capacity of s o i l colloids for holding cations. It i s expressed in terms of milliequivalent per 100 grams of s o i l (m.eq./lOO g) and i t is depen-dent upon the amount of clay minerals and organic colloids in the s o i l . Generally i t may be assumed that the organic colloids have a cation exchange capacity of 250 milliequivalent per 100 grams and that of the clay colloids is somewhere between 50 - 100 milliequivalent per 100 grams, because the clay fraction i s a composite of different clay minerals (Miller et a l . 1966). Cation exchange capacity has a significant role in soils as a reservoir of basic cations which can be u t i l i z e d as nutrients by plants, although they may be more or less replaced by hydrogen ions, particularly in humid climate regions. Cation exchange capacity of humus was measured and taken into consideration. No significant difference, however, was detected among the associations as analysis of variance indicated with the value of F = 0.UU, after a logarithmic transformation of raw data. V M G 0-A A-P 110 100 99 96 9h No particular correlation was found between cation exchange capa-city of humus and other factors. Although no significant s t a t i s t i c a l difference was found among the association with respect to cation exchange capacity of humus, a slight difference is observable among them regarding the accumulation 175 and nature of humus. The Vaccinium alaskaense association has a thick and compacted humus layer while the Oplopanax - Adiantum association shows a relatively well decomposed humus layer. 10) Cation exchange capacity of mineral s o i l s ; Cation exchange capacity of mineral soils i s , in general, much lower than that of humus, probably due to a lesser content of organic matter which is an important contributor to the cation exchange capacity of so i l s . Moreover, clay content, which also contributes to the cation exchange capacity is actually very low in mineral s o i l s , generally speaking, in the study area. Analysis of variance indicates that there i s a significant d i f f e r -ence with respect to the cation exchange capacity of mineral soils among the associations with the value of F = 5 . 7 7 which i s highly significant at the 1% level. Duncan's new multiple range test shows the relation among the as-sociations as follows: 0-A A-P M V G 27 19 18 16 15 Cation exchange capacity of mineral soils is positively correlated with f i e l d moisture (r = 0 . 5 8 ) , calcium content (r = 0 . 5 4 ) , nitrogen content (r = 0 . 5 2 ) and magnesium content (r = 0 . 5 1 ) . It is considered that the cation exchange capacity is basically correlated with organic matter, though the correlation coefficient i s not very high (r = 0 . 3 7 ) . The organic 176 matter is strongly correlated with f i e l d moisture and other factors. Consequently and indirectly, the cation exchange capacity is correlated with the factors shown above. 11) Calcium: Calcium is one of the elements the most influential upon soils as well as vegetation. Originally i t is contained in the parent material in the form of primary and secondary minerals such as c a l c i t e , dolomite, oligoclase, labradorite, anorthite, augite, hornblende and gypsum. It i s released gradually through weathering processes of the parent material and i t is brought into s o i l solution mostly in the form of replaceable cations which are readily available for plants. These cations are rather rapidly leached from soils with percolation of rain water under a humid climate, while in an arid region, they are deposited in the C horizon forming a sedimented layer of calcium carbonates (caliche). Calcium contributes considerably to the physico-chemical characters of soils and consequently to vegetation. Calcium acts as a neutralizing agent of s o i l acidity, as the pH values of soils are more of less positively correlated with the amount of calcium in the s o i l s . The high pH values of soils in calcium rich habitats provide favorable conditions for calcicolous and neutrophilous plants. Bacterial a c t i v i t i e s , in general, are also known to be stimulated by base-rich circumneutral habitats (Thimann 1 9 5 5 ) . Calcium is one of the essential elements for plants. It is a major constituent of calcium pectate which construct the middle lamella of c e l l walls (Devlin 1 9 6 9 ) . It is also suggested (Hewitt 1963) that calcium contributes to normal mitosis as the deficiency of i t causes abnormal mitosis. Calcium is also believed to be an activator for some enzymes (Devlin 1 9 6 9 ) . 177 When plants encounter a calcium deficiency, they show striking symptoms, i.e. l ) deterioration of a normal mitosis of meristematic tissue and subsequent termination of growth, 2) malformation or distortion of younger leaves, and 3) chlorosis and subsequent necrosis of the leaf-margins in younger leaves (Devlin 1969). Thuja plicata is known to be particularly sensitive to calcium deficiency, showing the characteristic symptoms (Krajina 1959a, 1969). Indeed, the die-back phenomena of Thuja plicata, caused possibly by a calcium deficiency, are relatively commonly observable in the f i e l d . In the present study, calcium content in soils is expressed in terms of equivalents per 1 cubic metre of s o i l ( l square metre x 1 metre depth below the ground surface). Analysis of variance indicates that there is a significant difference as to the calcium content among the associations with the value of F = 23.41* which is significant at the 1% level. Duncan's new multiple range test shows the following relations among the associations: 0-A A-P M V G 73.9 32.9 13.U 13.2 9.3 Because most of the calcium cations are transported and sup-plied to the habitats by seepage, calcium content is naturally correlated with f i e l d moisture (r = 0.53). Calcium cations are retained frequently in soils combined with organic and clay colloids, resulting in the increase of base saturation both in humus (r «= 0.58) and mineral soils (r = 0.68). 178 One of the most important roles of calcium is a neutralization of s o i l acidity. Thus, calcium content isitrongly correlated with the pH values of humus (r = 0.7l) as well as mineral soils (r = 0,70). The neutralized habitats, where calcium content is relatively high, are favourable for nitrogen fixation. Thus, nitrogen content increases with calcium content (r = 0.U5). These habitats also promote the production of organic matter which results in the increase of organic matter in the soils and subsequent increase of cation exchange capacity. Therefore, calcium content appears to be indirectly correlated with cation exchange capacity of mineral soils (r = 0.5k). Calcium content is strongly correlated with the amount of magnesium (r = 0.83). These two kinds of cations are chemically very similar and originally are contained together in various primary minerals. These two, therefore, behave more or less in the same way. Becket (l96Ua) treated (Ca + Mg) as one ionic species. The sequence of the associations along the calcium gradient is a result of aforementioned interractions of various factors. In other words, the sequence i s not only a reaction of vegetation according to the calcium gradient but also a manifestation of complex interractions of factors as mentioned above. 12) Magnesium: Magnesium is also a very important element which i n f l u -ence the physico-chemical characters of soils and consequently the vege-tation. Similar to calcium, i t is derived from primary and secondary miner-als which are contained in the parent material. Out of these minerals,dolo-mite and serpentine contain such a large amount of magnesium that a special 179 vegetation develops on the soils derived from these parent materials (Braun-Blanquet 1932). The role of magnesium in soils i s more or less similar to that of calcium. Generally the amount of magnesium in soils is less than that of calcium, but more than that of potassium. Magnesium is also one of the essential elements for plants. It is not only an essential constituent of the chlorophyll molecule, but also an important activator for enzymes which are involved in carbohydrate meta-bolism. It is also an activator for enzymes concerned with the synthesis of DNA and RNA, It was suggested that magnesium might be a binding agent between protein and RNA in microsomes (T'so_3t_al, 1957). The most charac-t e r i s t i c symptoms of magnesium deficiency is extensive intervein chlorosis of the leaves. It usually starts from basal old leaves and reaches up to younger leaves as the deficiency becomes serious. In the f i n a l stage of the deficiency, an occurrence of spotting necrosis i s observable, followed by the death of the plant (Devlin 1 9 6 9 ) . "Magnesium bar" is also one of the charac-t e r i s t i c symptoms of the magnesium deficiency (Krajina 1971, personal com-munication). When Pinaceae plants encounter the shortage of magnesium, they show chlorotic bars on the leaves, which appear at a right angle to midribs. These bars later turn necrotic followed by the complete collapse of the function of the leaves. Out of four coniferous species (Picea sitchensis. Pseudotsuga menziesii. Thuja plicata and Tsuga heterophylla) growing in British Columbia, Thuja plicata and Picea sitchensis were found to be the most sensitive to magnesium deficiency (Krajina 1959a, 1 9 6 9 ) . In the present study, magnesium content i s expressed in terms of equivalents per 1 cubic metre of s o i l , the same as the other cations. Analysis of variance indicates that there is a significant difference regarding the 180 content of magnesium among the associations with the value of F = 19.41 which is highly significant at the 1% level. Duncan's new multiple range test shows the relation of the associations as follows: 0-A A-P V M G 10.5 6.0 3.1 2.7 2.0 Magnesium content is strongly correlated with calcium content (r = 0.83), since these two elements are more or less chemically similar and they tend to behave in a similar fashion as was discussed in the previous section. Therefore, frequently soils rich in calcium are similarly rich in magnesium. Magnesium content i s also correlated with f i e l d moisture (r = 0 . 5 2 ) , pH of humus (r = 0 . 5 0 ) as well as the C horizons (r = 0 . 5 2 ) , cation exchange capacity of mineral soils (r = 0 , 5 l ) » base saturation of humus (r = 0.46) as well as mineral soils (r = 0.43), and amount of nitrogen (r = 0.4o). The physical and chemical properties of magnesium in soils are considered to be more or less similar to those of calcium, therefore, these correlations would be explained by the same reasons in the case of calcium. Soils richer in magnesium than in calcium (such as serpentine soils) were not discovered in this study area. 181 13) Sodium: Sodium i s widespread i n nature. I t i s an important component of feldspar i n rocks, and i t i s supplied to s o i l s through the weathering processes of the minerals. Rainwater also supplies a f a i r l y large amount of sodium to s o i l s , especially i n coastal regions. Sodium should not be a l i m i t i n g factor to plant growth, since i t i s so abundant i n s o i l s and i t i s not necessarily an essential element to most of the higher plants (Stout and Johnson 1957). The physiological role of sodium i n plants i s not presently w e l l known. There i s no evidence that i t i s actually essential in the metabolism of higher plants, though i t i s always present i n the ash. I t may be substituted by potassium when i t becomes deficient (Meyer e_t a l . I960). Sodium i s again expressed, i n the present study, i n terms of equiv-alent per 1 cubic metre of s o i l , as was done with the other cations. Analysis of variance indicates that there i s no s i g n i f i c a n t difference concerning the content of sodium i n the s o i l s among the associations with the value of F = 1.29. A-P 0-A V M G 1.68 1.57 1.53 1.38 1.21 In t h i s study sodium content does not show any p a r t i c u l a r correlation with other factors. 182 lk) Potassium; Potassium is derived from the primary minerals such as orthoclase, microcline, muscovite and b i o t i t e , and the secondary minerals such as complex alminosilicates. Although the amount of potassium in soi l s is usually less than that of bivalent cations, i t is supposed to be enough for plant growth except for the cases of very coarse sandy soils and organic s o i l s , since clay i s a major source of potassium. Potassium, in an exchange-able form, is subject to rapid leaching with percolation of water. The leached potassium from the surface s o i l s , however, may be trapped and fixed into lattices of clay particles, when clay is abundant in the subsurface soils (Reitemeier 1 9 5 9 ) . Potassium is one of the essential elements for plants, though i t s physiological role in plants is not well known. Generally, high concentrations of potassium are found in the meristematic tissues of plants. Potassium deficiency symptoms are mottled chlorosis followed by necrosis at the tips and margins of leaves and a stunted growth with abnormally shortened internodes (Devlin 1 9 6 9 ) . In the present study, potassium content in the soils i s expressed in terms of equivalent per 1 cubic metre of s o i l , the same as the other cations. Analysis of variance indicates that there is a significant difference among the associations regarding the potassium content with the value of F = 5 . 9 8 which is significant at the 1% level. Duncan's new multiple range test shows the relations of the associations as follows: V M G A-P 0-A 0 . 9 6 0 . 8 0 0.72 0 . 6 5 0.42 183 Potassium content is negatively correlated with the pH values both of humus (r = -0.1+0) and the C horizon (r = -0.1+2). There is a peculiar feature, as is shown above, in regard to the sequence of the associations. Very different from the cases of other cations such as calcium and magnesium, the associations are rather converse-ly arranged along the potassium gradient, as the Vaccinium alaskaense association i s ranked the highest and the Oplopanax - Adiantum association the lowest. This fact can be explained as an antagonistic relation be-tween potassium cations and other bivalent cations. When bivalent cations, especially calcium cations, are prevailingly present, potassium cations are forced to yi e l d the cation sites to them, because bivalent cations are more powerful than those of potassium in terms of the cation exchange efficiency (Miller et a l . 1966). It is also known that the relation between potassium and other bivalent cations is on an equilibrium status as is shown in K/ (Ca + Mg) (Becket 1961+a). Thus the amount of potassium in the soils in neg-atively correlated with calcium content (r = -0.28) and the magnesium content (r = -0.13) though the correlation coefficients are not very large. The negative correlations between the potassium content and the pH of humus as well as the C horizons can be explained by the same reason as above. 1) 15) Organic matter: The amount of organic matter in soils was caluculated by multiplying the content of carbon with 1.721+, based on the assumption that the humus incorporated in the mineral s o i l contains 58% carbon (Lutz and Chandler 19^6). The source of organic matter i s , needless to say, 1) The amount includes organic matter in L-H horizon. 184 organic residues supplied by various organisms. In forest ecosystems, the most significant contributor to the accumulation of organic matter is forest trees. The amount of organic matter in s i t u represents the balance that has been attained over a number of years between the processes of decomposition and the supply of l i t t e r from trees and the associated vegetation (Ovington 1 9 5 3 b ) . The amount of organic matter (m) in a s o i l at a given time t_may be defined by following equation (Ogawa et_ a l . 1 9 6 l , _ t Olson 1 9 6 3 ) : m = (L/u)(l-e -^ ) where L is the rate of organic matter sup-plied to the s o i l , e i s a base of natural logarithm and )i i s a factor char-acterizing the rate of decomposition. The amount of organic matter added to the ecosystem is very variable depending upon the environmental condi-tions. Bray and Gorham ( 1 9 6 4 ) recognized that macroclimate is the pre-dominant factor which influences the l i t t e r production rate in the world, estimating the annual l i t t e r production in different regions as follows: 1) 1 . 0 in arctic - alpine region; 3 . 5 in cool temperate region; 5 . 5 in warm temperate region; and 1 0 . 9 in equatorial regions. Within the same climatic and pedological conditions, the amount of organic matter differs depending upon kinds of vegetation. Ovington ( 1953b) estimated a t o t a l weight of forest floor organic matter under different tree species, most of which were about twenty years old, growing on similar habitats in south England, 2) as follows: Pinus nigra stand 23 ,699 Picea omorica stand 2 2 , 4 2 9 ; Tsuga  heterophylla stand 1 2 , l 6 0 ; Thuja plicata stand 12,131; Pseudotsuga  menziesii stand 10,931; and Abies grandis stand 6 , 5 9 2 . 1) expressed in metric ton/ha/year 2) expressed in kg/ha (oven dry weight) 185 Decomposition rate of organic matter is also subject to effects of factors such as climate, s o i l conditions, and kind of vegetation. Generally, there is an inverse relationship between mean annual temperature and level of organic matter in regions of comparable r a i n f a l l (Jenny 19^1), since high, but not excessive temperature promotes microbial activity and consequent decompostion of organic matter. Good aeration also stimulates the decomposition of organic matter. High precipitation i s unfavorable. Thus, water-logged organic matter under a cool and humid climate i s de-composed extremely slowly. S o i l chemical conditions also highly affect the decomposition rate. Generally, nutrient rich habitats with relatively high pH values are preferable. Calcium is the most influential factor on the decomposition of organic matter. It acts as neutralizer of acidic substances which are produced through the decomposing processes, providing favorable conditions for further microbial activities (Lutz and Chandler 19^6). Wiedemann (1924) pointed out that decomposition of organic matter was promoted more in soils derived from basic rocks than in soils from acidic rocks. Kinds of vegetation are also important in affecting the decomposi-tion rate of organic matter. It is known that, as a rule, the l i t t e r of deciduous trees is more rapidly decomposed than that of conifers (Lutz and Chandler 19*+6). This is probably due to the difference in the chemical character of the l i t t e r . Compared with the l i t t e r of deciduous trees, that of conifers is generally characterized by lower pH value, lower content of calcium, lower content of nitrogen and consequent wider carbon-nitrogen ratio (Ovington 1953b). Humus is a to t a l expression of the complex interactions of the 186 aforementioned factors. There are two main categories of humus: mor and mull. The mor category of humus is characterized by a thick carpet-like formation of organic matter which i s sharply bounded from the underlying mineral s o i l s . It i s rather acidic and generally associated with conifer-ous stands under a cool and humid climate. Activities of fungi predominate over those of bacteria in the mor humus. On the other hand, the mull category of humus is characterized by the f a i r l y well decomposed plant residues which are friable in nature and less acidic. It is so well mixed with mineral particles that the boundary between humus and mineral horizon is rather obscure. In this humus, bacteria are more active than fungi, and earthworms are usually present. Development of the mull humus is asso-ciated with mostly deciduous forests and mixed forests. Ovington (1953a, 1953b) recognized that formation of a particular humus type was rather strongly controlled by kinds of vegetation under the same climatic and pedological conditions. Generally in the coastal western hemlock zone, under the cool and perhumid climate, the mor type of humus is considered to be a typical humus overlying podzols, associated with Tsuga heterophylla forests. In the present study, the amount of organic matter is expressed in terms of kg/cubic metre of s o i l , which was calculated based on the percent-age of organic matter in different horizons. The analysis of variance indicates that there is a significant difference among the associations regarding the amount of organic matter with the value of F = 3,46 which i s significant at the 5% level. Duncan's new multiple range test shows the relations among the associations as follows: 18 7 0-A V A - P G M 38.6 37 .7 30.3 25.3 25 .0 As was stated ea r l i e r , the amount of organic matter in soils represents a balance of supply and consumption of i t . In the Oplopanax -Adiantum association, where the habitats are very rich in nutrients as well as water, the rate of supply of organic matter from the vegetation presume ably exceeds the rate of microbial decomposition which is also promoted by base rich circumneutral habitat conditions, with a consequence of increasing the organic matter in the s o i l s . I n this association, the organic matter takes the form of semi-terrestrial moder or mull (Kubiena 1953) , well de-composed and humified, which is somehow related to black muck humus in "skunk cabbage" sites. A situation in the V a c c i n i u m alaskaense association i s , however very different from the aforementioned case, although i t belongs to the same rank as the Oplopanax - Adiantum association s t a t i s t i c a l l y . The V a c c i n i u m  alaskaense association is under a strong influence of a perhumid climate. T h e r e f o r e , s o i l s , as a result of a strong leaching, are so acidic and poor in nutrients that decomposition processes are rather slowed. T h i s results in increasing the organic matter even i f a supply rate is also low. R e l -atively high amount and long duration of snow also promote a thick accu-mulation of raw humus in the form of mor. Thus , the situations between the two associations are quite d i f -ferent even though superficially they belong to the same rank. 188 Other cases of the associations are more or less similar to each other. They develop on relatively drier habitats where both the decomposition rate and supply rate of organic matter are moderate, resulting in the moderate accumulation of organic matter in the s o i l s . The amount of organic matter is positively correlated with the nitrogen content (r = 0.66) and f i e l d moisture (r = 0.U3). Since most parts of nitrogen in soils take the form of organic matter, the relation between these two is understandable. Field moisture, which is indicative of the seepage effect, would contribute to the accumulation of organic matter by promoting the productivity of the community as a result of the high amount of nutrient supply as well as water. l6) Nitrogen; The importance of nitrogen for plants cannot be over-emphasized. It i s one of the essential elements which is involved in the basic construction of protein molecules and other very important molecules such as purines, pyrimidines, porphyrines and various coenzymes. In other words, nitrogen is a part of l i f e i t s e l f . The primary source of nitrogen in an ecosystem is atmospheric nitrogen, although i t is not available directly to most of plants. Nitrogen fixation i s a major influx route of nitrogen into the ecosystem. Through this process nitrogen is converted into substances which are readily a v a i l -able to plants. As autotrophic nitrogen fixers, Azotobacter and Clostridium are the most representative. Azotobacter species are favored by good aera-tion, abundant organic matter, presence of a relatively high amount of calcium and phosphorus, and circumneutral or slightly alkaline s o i l conditions, while Clostridium species are active under anaerobic and acidic conditions (Thimann 1955, Brock 1966). Besides these, some species of Nostocaceae are also 189 known to f i x atmospheric nitrogen under warm and humid climate. Especially Tolvpothix tenuis were found to be able to f i x nitrogen up to 885 kg/ha/year (Tamiya 1 9 5 7 ) . Of the symbiotic nitrogen fixers, Rhizobium leguminpsarum is the best known and ecologically significant. Lyon (1934) reported that Rhizobium together with a l f a l f a (Medicago sativa) fixed nitrogen up to 2 0 0 -250 lbs/acre/year. Rhizobium species are particularly important at an early stage of primary succession of plant communities. By adding an extra amount of nitrogen to the habitats, they provide more suitable habitats for esta-blishment of other plants which might enter the sites later with the progress of the succession. There are a number of microorganisms which are known to f i x nitrogen symbiotically. The mechanisms of transfer of the fixed nitrogen to the host plants are not well known yet. It i s , however, speculated that calcium is promotive to the mechanism, since calcium deficiency result in a decreased supply of the fixed nitrogen (Banath et a l . 1 9 6 6 ) . There is another important biogeochemical process concerning the circulation of nitrogen in an ecosystem, that i s , n i t r i f i c a t i o n . It is a two-step process through which ammonia is ultimately converted into nitrates which are the most important nitrogen source for most of plants. It is medi-ated by two groups of microorganisms: Nitrosomonas group and Nitrpbacter group. N i t r i f i c a t i o n i s promoted by circumneutral to slightly alkaline soils with good aeration, in contrast to the ammonification which is favored by acidic conditions (Lutz and Chandler 1 9 4 6 , Thimann 1 9 5 5 ) . N i t r i f i c a t i o n i s indicated by the presence of nitrophilous plants such as Sambucus pubens. Ti a r e l l a t r i f o l i a t a , Tolmiea menziesii, Tellima grandiflora and Urtica dioica ssp. l y a l l i i (Krajina 1 9 6 9 ) . 190 Most nitrogen in soils takes the form of organic matter, chiefly protein (ligno-protein and clay-protein complexes), which are derived from organic residues. Out of decomposed organic matter, some of the protein is absorbed on the surface of clay minerals and becomes highly resistant to attack from microbial a c t i v i t i e s . To a certain extent, the content of nitrogen in s o i l i s proportionate to the amount of organic matter. As the inorganic form of nitrogen in s o i l s , the major forms are ammonia in acid soils and nitrates in circumneutral s o i l s . From greenhouse experiments, Krajina ( 1 9 5 9 a , 1969) recognized that Tsuga heterophylla was well adapted to the ammonium form of nitrogen as a nutrient, while Pseudotsuga menziesii could not tolerate i t and the species was favored by the nitrate form of nitrogen source. In the present study, nitrogen content in soils is expressed in terms of grams per 1 cubic metre of s o i l . Analysis of variance indicates that there i s significant difference among the associations in respect to the nitrogen content with the value of F = 9 . 6 5 which i s highly s i g n i f i -cant at the 1% level. Duncan's multiple range test shows the relations among the associations as follows: 0-A V A-P M G 880 662 627 1+61 k02 In the present study, the nitrogen content in soils i s positively correlated with the amount of organic matter (r = 0 . 6 6 ) , f i e l d moisture 191 (r = 0.66), cation exchange capacity of mineral soils (r = 0.52), the amount of calcium (r = 0.U5), and the amount of magnesium (r = 0.U0), It is negatively correlated with clay content (r = -O.M) and the carbon-nitrogen ratio of mineral soils (r = -0.U3). The correlation between the nitrogen content and the amount of organic matter is quite understandable, since most parts of nitrogen take the form of organic matter. The f i e l d moisture, being relatively highly correlated, would indirectly contribute to the nitrogen content in such a manner that i t supplies various cations to the habitats and provides favorable conditions for nitrogen fixation. There are two possible explanations for the correlation between the nitrogen content and the cation exchange capacity of mineral s o i l s . One is a mere correlation or indirect correlation. The cation exchange capacity of mineral soils may be correlated essentially with organic matter, since organic matter is an important contributor to cation exchange capacity of s o i l s . Nitrogen content is also correlated with the amount of organic matter, as was discussed earlier. In consequence, s y l l o g i s t i c a l l y cation exchange capacity of mineral soils may be correlated with the nitrogen content. Another possibility is that cation exchange capacity may act as a nitrogen holder in the soils when nitrogen takes the form of ammonium ions. Nevertheless, this possibility is doubtful, since ammonium ions in the soils occupy only a small portion of t o t a l nitrogen, moreover, the proportion of the ammonium ions would become much smaller in cation-rich circumneutral habitats where nitrogen content, as a t o t a l , actually increases, since acidic s o i l conditions are favorable for ammonification. The correla-tion between nitrogen content, and the amount of basic cations such as calcium and magnesium is also understandable, because, i t is well known 192 that generally calcium stimulates the microbial activities including nitrogen fixation. N i t r i f i c a t i o n is also promoted on calcium rich habitats. The nitrogen content is correlated negatively with carbon-nitrogen ratio. This is self-explanatory. Nitrogen is nothing more than a denominator of the ratio. There is also a negative correlation between the nitrogen content and the clay content. This would be the case of an indirect correlation, since rich clay content, in general, tends to give the soils low pH values as a result of an association with high amount of hydrogen ions especially under a humid climate. The amount of nitrogen in soils is proportionate to the amount of organic matter to a certain extent, since nitrogen is originally and mostly contained in the organic matter. Nitrogen, however, does not show a perfect correlation with the amount of organic matter as i t is seen in the correlation coefficient (r = 0.66). Moreover, the ranking and grouping of the associations according to Duncan's new multiple range test in respect to the nitrogen content shows a very different figure from that of the organic matter. This fact implies that the nitrogen content is not simply proportionate to the amount of organic matter. In other words, some other factors may differently affect the distribution of nitrogen in the associa-tions. The difference of nitrogen content for the association probably would be due primarily to the different rate of consumption of organic matter, particularly that of carbohydrates, by microorganisms. In the Oplopanax -Adiantum association, in which the nitrogen content was found to be the highest among the associations, habitats are f a i r l y favourable for microbial act i v i t y , since the habitats contain relatively high amounts of calcium and magnesium, and consequently base saturation as well as pH values are 193 also high. Therefore, a high rate of microbial activities would be expected resulting in the high consumption of carbohydrates in the habitats.. Most of the nitrogen, however, would remain .in the soils as parts of protoplasm and other constituents of bodies of the microorganisms. A consequence of this would be an increase in the proportion of nitrogen to amount of organic matter. Under these circumstances, a high rate of asymbiotic nitrogen f i x -ation is expected because of the favorable habitat conditions. This would cause the further increase of nitrogen in the sites. Thus, in the Oplopanax - Adiantum association and the Achlys - Polystichum association, nitrogen fixation would take place with a relatively high rate. This i s re-flected in the carbon-nitrogen ratio as these associations show the lowest ratio among the associations. Nevertheless, the important role of organic matter should not be disregarded. It can s t i l l control the basic amount of nitrogen in s o i l s , since nitrogen is essentially a part of organic matter. Particularly, the Vaccinium alaskaense association which has the second highest nitrogen content, would be regarded as the case where the nitrogen content should be referred to the to t a l amount of organic matter. Williams and Dyrness (1967), comparing seven forest types which occurred in the Cas-cade Range in respect to the amount of the to t a l nitrogen in the forest floor, recognized that the pacific silver f i r - western hemlock forest type had the highest value (approximately 1.1%) for nitrogen and i t was more or less proportionate to the to t a l amount of forest floor weight which was also the highest in this forest type. In the Oplopanax - Adiantum association and Achlys - Polystichum association, where habitats are rich in basic cations and consequently less a c i c i c , presumably a high rate of n i t r i f i c a t i o n is expected resulting in 194 yielding a relatively high amount of nitrates which are readily available to plants. Therefore, in these associations, the circulation of nitrogen in the biogeochemical cycling is considered to be very fast. This would be one of the causes of high productivity of the sites. On the other hand, in the Vaccinium alaskaense association in which the habitats are comparatively poor in basic minerals and consequently soils are strongly acid, the decomposition of organic matter is very slow resulting in an accumulation of thick raw humus (mor) on the forest floor. Under such circumstances, the n i t r i f i c a t i o n hardly takes place. Most of the imperfectly decomposed nitrogen compounds remain in the form of ammonium which i s hardly usable by most of the plants. A circulation of nitrogen through the biogeochemical cycling i s expected to be slow in this association. The cases of other associations are presumed more or less inter-mediate between the two mentioned above. The n i t r i f i c a t i o n , however, is probably rather impeded in these associations, since humus seems already too acid for the processes. 17) Available phosphorus: Available phosphorus is a relatively soluble form of phosphorus which can be immediately absorbed by plants. Usually i t takes the form of HgPO^ and HPOjj" . Availability of phosphorus is very variable depending upon l ) pH of the s o i l solution, 2 ) amount of iron and aluminum oxides, 3) amount of calcium cations, 4 ) anion exchange status, and 5) rate of microbial activity (McAuliffe et a l . 1 9 4 8 , Olsen 1 9 5 3 , Olsen and Fried 1 9 5 7 ) . Because of the great v a r i a b i l i t y in chemical composition and high susceptibility to other conditions, amounts of phosphorus in soils is also variable, and i t is generally rather small (Lutz and Chandler 1 9 4 6 ) . 195 There are two basic forms of phosphorus in s o i l s , i.e. inorgan-i c and organic. The major source of inorganic forms of phosphorus is the apatite group of minerals. As the weathering of the minerals proceeds, the amount of the iron phosphates and aluminum phosphates increases, because the hydrous iron and aluminum oxides which are the products of weathering processes have high capacity of holding phosphorus, they are more stable to weathering processes. The inorganic phosphorus, after being absorbed and assimilated into protoplasm by plants, takes the form of organic phosphorus and then i t is brought into the processes of the biogeochemical cycles in an ecosystem. Organic phosphorus takes the form of inositol group of phosphates, phospholipides, and unidentified organic compounds. Organic phosphorus is subject to microbial decomposition and i t is converted easily into inorganic phosphorus, especially when the s o i l pH is high. Therefore, the amount of organic phosphorus tends to be higher in acid soils than in alkaline s o i l s . Organic phosphorus is more or less associated with the amount of nitrogen in the so i l s . The organic form of phosphorus, however, cannot be u t i l i z e d by plants, unless i t is converted into an inorganic form by microbial a c t i v i t i e s . When the organic phosphorus is decomposed by saprogenic bacteria, the phosphorus is s p l i t from the organic compounds and takes the form of phosphoric acid. The phosphoric acid immediately unites with any alkali to form soluble or insoluble phosphate. If soluble phosphates are formed, the element may be directly assimilated by plants, being built up into protoplasm, and the cycle i s completed. As insoluble form of phos-phate, calcium phosphate is the most common in nature (Thomas and Grainger 1952). Thus, in rea l i t y , the available phosphorus is a mixture of phosphorus from two different sources, i.e. phosphorus derived from primary minerals through the weathering processes, and that released from organic matter 1 9 6 through the microbial decomposition processes. Phosphorus i s , of course, one of the essential elements for plants. It i s a fundamental constituent of nucleic acids, phospholipides, nucleotides such as ADP and ATP, and some kinds of coenzymes. Thus, phosphorus is direct-l y involved in protein synthesis procedures and energy metabolism. P a r t i -cularly heavy concentrations of phosphorus are recognized in the meristematic regions of actively growing plants (Devlin 1 9 6 9 ) . Krajina ( 1 9 5 9 a ) , through greenhouse experiments, recognized that Tsuga heterophylla and Thuja plicata were more tolerant to low supply of phosphorus than Pseudotsuga menziesii and Picea sitchensis. In the present study, the amount of available phosphorus in soils is expressed in terms of grams per 1 cubic metre of s o i l . The values are generally low. Analysis of variance indicates that there i s no significant difference among the associations in regard to the content of available phosphorus with the value of F = 1 . 8 0 . M V A-P G 0-A 2 . 3 2 . 1 2 . 1 1 .5 1 . 2 The amount of available phosphorus does not show any particular correlation with other factors. 18) Slope; Slope i s also an important factor which affects vegetation, both directly and indirectly. Slope gradient together with i t s exposure 197 controls the effectiveness of insolation and modifies the amount of radia-tion available to the habitats. Consequently i t affects the temperature of the ground surface (Oosting 1 9 5 6 , Mowbray and Oosting 1 9 6 8 ) . Steepness of the slope influences the movement of ground water as well as the velocity of runoff after rain (Daubenmire 1 9 ^ 7 ) . Slope gradient acts occasionally as a differentiating factor of community types together with wind influence and snow accumulation, especially in severe conditions of alpine environ-ments (Patten 1 9 6 3 , Suzuki and Hutamura 1 9 6 6 , Brooke et, a l . 1 9 7 0 , Eady 1 9 7 0 ) . In the present study, the slope factor is taken into consideration. Slope gradient i s expressed in degrees. Analysis of variance shows a signi-ficant difference among the associations with the value of F = 3 . 7 3 which is significant at the 1% level. Duncan's new multiple range test shows the following relations among the associations: G M A-P 0-A V 17 15 11 10 k The sequence of the associations along the slope gradient, shown above, corresponds to the hygrotopic and topographic sequence of the associa-tions, except for the case of the Vaccinium alaskaense association. This i s quite understandable because these associations tend to be arranged from ridge top to the bottom of valleys according to topographic situations, and generally the slope gradient also decreases from upper position to lower one on the slope. 198 Although the Vaftcin-ium alaskaense association shows a very small value of average slope gradient in the present study, i t seems not to he an essential condition for the association, since the association usually oc-curs on mesic habitats covering extensive areas under the perhumid climate. The small value obtained i s the result from the fact that some of the plots from the association were established on old river terraces where the topography was almost f l a t . Slope gradient does not show any particular correlation with other factors. In addition to t h i s , the importance of the surrounding topography cannot be disregarded, especially in relation to the supply of seepage water. Indeed, the distribution of the Achlys - Polystichum association as well as the Oplopanax - Adiantum association i s more highly controlled by the presence of seepage water or running water rather than the slope grad-ient of the site i t s e l f . Similarly, because other associations develop on non-seepage habitats, they are incidentally correlated with steeper topo-graphy of upper slopes on which seepage i s actually not existent. Thus, i t may be concluded that seepage effect i s more i n f l u -ential upon the distribution of association than the slope gradient i t s e l f and slope gradient i s only significant when i t is related to the seepage effect. 199 19) Carbon-nitrogen ratio of humus: Carbon-nitrogen ratio i s an i n d i -cator of s o i l f e r t i l i t y , especially of nitrogen. Usually carbon-nitrogen ratio of humus, as well as mineral s o i l s , is narrower than that of fresh plant leaves and undecomposed l i t t e r , because, as the organic debris is decomposed, most of the carbohydrates are consumed by micro-organisms as an energy source, while nitrogen mostly persists in the soils incorporated in the structure of microorganisms or combined with clay particles forming clay-protein complexes which are highly resistant to microbial attack. Thus, the ratio of carbon and nitrogen becomes narrower in s o i l than in fresh organic debris. The value of the ratio i s , however, very variable depending upon environmental conditions, i.e. kind of l i t t e r , s o i l pH, and kind and rate of microbial a c t i v i t i e s . Ovington (1953b) reported that generally carbon-nitrogen ratio of fresh leaves of conifers were much wider than that of deciduous trees, for instance, Picea omorica 58.1; Pinus nigra 55.**; Thuja plicata 51.8; Pseudotsuga menziesii U8.U; Tsuga heterophylla 40.2; whereas Fagus sylvatica 22.2; Nothofagus obliqua 22.2; Quercus  rubra 20.2; Quercus petraea 19.3. A similar tendency was also recognized regarding the carbon-nitrogen ratio of the forest floor. Circumneutral and slightly alkaline conditions of soils tend to narrow the values, since such habitats stimulate microbial activity, especially that of bacteria, which would result in the high consumption of carbohydrates and consequently narrow the ratio. On the other hand, on acidic habitats where major micro-b i a l activities are carried out by fungi, the ratio remains more or less wide since fungous activities decompose the organic matter incompletely, producing various kinds of organic acids in which cabon is a basic component. Thus, fungous activities do not result in a narrowing of the carbon-nitrogen 200 ratio as much as bacterial, Waksman (1938) calculated an average value of carbon-nitrogen ratio of humus to be approximately 10, assuming that carbon content in humus is 56% and nitrogen content 5.6%. This value, however, seems to be too small to apply to most of the humus. The carbon-nitrogen ratio of forest floors and humus is highly variable and mostly greater than 10 (Lutz and Chandler 1946). Isaac and Hopkins (1937) reported the carbon-nitrogen ratio in forest floor of Douglas-fir stands to be about 57 and that of the mineral soils to be about 24. Ovington (1953b) obtained carbon-nitrogen ratio of forest floor of different tree stands as follows: Picea  omorica stand 37.8; yhuia plicata stand 32.0; Pinus nigra stand 30.5; Pseudotsuga mensiesii stand 27.3; Tsuga heterophylla stand 25.9; Fagus  sylvatica stand 25.0; Nothofagus obliqua stand 26.3; , Quercus rubra stand 25.8. In the present study, carbon-nitrogen ratio of humus i s , in gen-eral, rather wide and variable. Analysis of variance, therefore, does not detect any significant difference among the associations in regard to the carbon- nitrogen ratio, and i t suggests that the variations within asso-ciations are greater than those of between associations with the value of F = 0.60. V 0-A G A-P N 45 38 37 35 34 Because the variations within associations are so large, the sequence of the associations shown above does not signify anything in 201 particular. 2 0 ) Carbon-nitrogen ratio of mineral s o i l s ; Carbon-nitrogen ratio of mineral soils i s generally lover than that of humus. This i s probably due to the relative increase of nitrogen in the mineral s o i l s , since organic matter brought into the mineral soils has been more or less well decomposed. Some of the protein compounds might have been combined with clay particles forming clay-protein complexes which have remained unaffected by microorganisms' attack. This kind of protein would make the ratio narrower. Different from the case of humus, a significant difference was found among the associations in respect to the carbon-nitrogen ratio of mineral soils with the value of F = 7.57 which is highly significant at the 1% level. Duncan's new multiple range test show the relation among the associations as follows: G V M A-P 0-A 5 2 3 5 3 U 2 8 26 This tendency of the carbon-nitrogen ratio can be explained by the reason which was fu l l y discussed in the section on "nitrogen". brief-l y , i t depends upon the rate of microbial a c t i v i t i e s . Especially in the Achlys - Polystichum association and the Oplopanax - Adiantum association, 202 where the habitats are rich in basic minerals and less acid, a relatively-high rate of nitrogen fixation as well as n i t r i f i c a t i o n i s expected. This would increase the nitrogen content in the habitats and consequently make the carbon-nitrogen ratio smaller. There is a negative correlation ( r = -0.1+3) between carbon-nitro-gen ratio of mineral soils and the nitrogen content. This i s , however, self-explanatory, since the nitrogen content is the denominator of the ratio. There is another negative correlation, between the carbon-nitrogen ratio of mineral soils and base saturation of mineral soils (r = -0.1+3). This is due to the same reason as the case of calcium content, since base saturation is dependent highly upon the amount of calcium. Actually, base rich habitats stimulate microbial activities which result in the increase of relative amounts of nitrogen by consuming high amounts of carbohydrates and fixing extra amounts of nitrogen with a consequent narrowing of the carbon-nitrogen ratio. 21) Base saturation of humus: Base saturation is a percentage of the total amount of exchangeable basic cations (calcium, magnesium, sodium and potassium) to the total amount of cation exchange capacity of a s o i l . It is an indicator of s o i l f e r t i l i t y , especially of basic minerals. It varies greatly depending upon the environmental conditions such as climate, topo-graphy, parent material, moisture regime, kind of vegetation, age of the s o i l and so on, since i t is one of the dynamic properties of s o i l . Under humid climates, the base saturation is generally low due to strong leaching of cations, whereas in arid regions i t is generally high, particularly when 203 precipitation of calcium carbonates exists in the C horizon. Here i t may-attain more than 100%t and s o i l pH is also high. Within the same humid c l i -matic conditions, i t i s influenced by moisture regime. When seepage is pre-sent, soils tend to show higher base saturation than non-seepage s o i l s , since seepage is an important source of exchangeable cations. Thus, topographical-l y , soils in the bottom of valleys tend to have higher base saturation than those of other situations. When the parent material contains relatively high amounts of cations, for instance limestone or basaltic rocks, obviously base saturation of overlying soils becomes high (McAleese and McConaghy 1 9 5 8 , McAlleese and Mitchell 1 9 5 8 ) . It is known that, under humid climate, base saturation usually decreases with age of the s o i l u n t i l i t reaches an e q u i l i -brium status (Crocker and Major 1 9 5 5 , Crocker and Dickson 1 9 5 7 ) . In the present study, base saturation is very high. The following table (Table 34) is a comparison of values of base orthic associations in the coastal western hemlock zone studied by Lesko ( l 9 6 l ) . Within the pairs of associations, the two are comparable to each other. Generally higher values of base saturation of the associations in the present study area than those of the orthic associations are the results of the strong influence of the base rich parent material in Strathcona Provincial Park area. Regarding the base saturation of humus, analysis of variance i n d i -cates that there is a significant difference among the associations with a value of F = 8 . 6 7 which is highly significant at the 1% l e v e l , after the cubic root transformation of raw data. Duncan's new multiple range test shows the relation of the associations as follows: 204 Table 34. Comparisons of base saturation of the associations in the present study with those of the orthic associations in the coastal western hemlock zone, reported by Lesko ( 1 9 6 1 ) . »«^^^Jfor^ Association L-H Base saturation {%) A B r G 26 19 12 UDe 16 9 4 TM 2 8 2 6 2 1 I T 19 14 14 f v 17 15 22 LAT 23 4 3 FA-P 2 8 3h 34 IP 24 24 9 ro-A 51 59 59 lo 17 25 G, M, V, A-P, 0-A: associations discussed in this thesis; De: dry edaphic communities; T: Tsugetum heterophyllae plagiotheciosum undulati; P: Thujeto - Polystichetum hylocomietosum splendentis; AT: Abieteto - Tsugetum heterophyllae; 0: Piceeto - Oplopanacetum. 205 0-A A-P M G V 51 32 29 2 6 18 Base saturation of humus is positively correlated with pH values of humus (r = 0.68) as well as mineral soils (r = 0.58), since the pH values are dependent, to a great extent, upon the base saturation (Steele 1955). It is also positively correlated with the amount of calcium (r = 0.58) and magnesium (r = 0,46). This i s quite self-explanatory, since the tot a l amount of cations i s the numerator of the percentage. cations, i t is apparent that the Oplopanax - Adiantum association, in which calcium cations are concentrated greatly, has the highest value of base saturation and the sequence of the association is very similar to that of calcium gradient, except for the relation of the l a s t two associations. In the case of the Vaccinium alaskaense association, strong leaching to-gether with high concentration of hydrogen ions would have caused the lowest base saturation of humus among the associations, even i f the calcium content is slightly higher than that of the Gaultheria shallon association. The amount of precipitation in the Vaccinium alaskaense association i s presum-ably the highest, and pH value of humus is actually the lowest among the as-sociations. Because base saturation is dependent upon the tot a l amount of 206 2 2 ) Base saturation of mineraj. so i l s t Base saturation of mineral soils shows a very similar tendency to that of the humus. However, i t has stronger positive correlations with calcium content (r = 0 . 6 8 ) and pH value of the C horizons (r = 0 . 6 3 ) . It is correlated also with pH value of humus (r = 0 . 5 3 ) , magnesium content (r = 0 . 4 3 ) and base saturation of humus (r = 0 . 4 3 ) . There i s a correlation with content of sand (r = 0.41), Sand is actually correlated with the Onlo-panax - Adiantum association in which the base satura-tion is the highest among the associations. Thus, consequently and indirectly the base saturation of mineral soils i s correlated with the content of sand. The base saturation is negatively correlated with carbon-nitrogen ratio of mineral soils (r = - 0 . 4 3 ) probably by the same reason which was discussed in the section on carbon-nitrogen ratio. Analysis of variance indicates that there is a significant d i f f e r -ence among the associations in respect to base saturation of mineral soils with the value of F = 1 2 . 5 3 which is highly significant at the 1% l e v e l , after the logarithmic transformation of raw data. Duncan's new multiple range test shows the relation among the associations as follows: 0-A A-P M V G 6 1 39 24 2 0 17 In contrast to the case of base saturation of humus, the sequence of the association in this case is identical with that along the calcium gradient. This fact would imply that the amount of calcium cations i s the 207 most contributing factor to the base saturation of mineral so i l s . The same as the case of humus, most of the mineral soils in the present study are also very high in base status (Table 3h) comparing with the soils in the orthic associations in the coastal western hemlock zone as analyzed by Lesko ( 1 9 6 1 ) . In some cases, base saturation was found to be more than 100%, This would be the result of presence of free calcium carbonate in the s o i l s , since the parent material may occasionally contain limestone. 208 B. The most influential factors upon the development of the associations According to Dokuchaev (1899), Jenny (1941, 196l) and Major (1951), the relationships between vegetation as well as s o i l and their environment is concisely defined by a following equation which is called "the state factor equation" (Jenny 196l) as: V,S = f(C, P, R, 0, T) (1) where V represents vegetation in a given area; S, s o i l ; C, climate; P, parent material or geological substratum; R, r e l i e f ; 0, organisms other than vegetation; and T, time factor. Although the equation is a philo-sophical model rather than a mathematical model, i t explains very well the complex nature of an acosystem. Because, more r e a l i s t i c a l l y , each state factor comprises a number of components, i t would be possible to s p l i t the state factors into compo-nents. Then the equation would become as follows: V,S ~ f(C^,Cg, • • • • ,Pj * *" * * * ^ i *^ 2 * * *" * *^1*^2 * * * * * *^1 *^ 2 * * * * * ^ *** where subscripts (l,2,...,n) are denoted to the number of components of each state factor. By substituting the components with variables X's in the equation (2), then the equation (3) w i l l be obtained: V,S = f(X ,X ,X ) (3) 1 2 m I f a l l the variables are measured and expressed on a quantitative basis, the model, thus, would be a mathematical model which permits a mathe-matical or s t a t i s t i c a l approach to be applied. 2 0 9 i . Multiple regression analysis Multiple regression analysis best f i t s the model. It is a regres-sion of a dependent variable on more than two independent variables. In other words, this is a case where one dependent variable is controlled by more than two independent variables. The following discussion is referred to by Draper and Smith (1966), Freese (1964), Kozak (1964, 1969, Kozak & Smith 1965), and L i (1964). The general model of the multiple regression is shown as follows: u. = /3 + fix + fix + + /9x ' y ' O / l i / 2 2 /mm where JHy is a mean of y, is an intercept of the regression surface, P2» i/3n a r e constants which are called p a r t i a l regression coefficients. Since the multiple regression analysis is carried out based on samples, the general model may be written as follows: Y = b Q + b l X l + b 2 x 2 + + b A The n u l l hypothesis for the regression analysis is b^= bg= ... ... - bm= 0, i.e. a l l partial regression coefficients are equal to zero. In other words, no independent variables contribute to the value of the dependent variable. The test is actually conducted by calculating the value of F, where Sum of squares of regression m F = Sum of squares of residues n - m - 1 Where n_ is number of observations taken into the calculation. When the value of F is significant, the n u l l hypothesis is rejected with an alternative hypothesis that at least one of the p a r t i a l regression 2 1 0 coefficients is not zero, i.e. the dependent variable y is affected by at least one of the indepndent variables. The next step is to select the best regression equation. There are some methods to select the most significant subset of independent va r i -ables from those originally involved. In the present study, a stepwise elimination methods modified and developed by Kozak ( 1 9 6 4 , Kozak & Smith 1965) was employed. The basic idea of the method is to eliminate the least significant variable from the set of the independent variables stepwise one by one, again based on the value of F which is calculated by the following equation: where F^ is a variance ratio for i-th independent variable, bj_ is a regres-sion coefficient for the i-th independent variable, and S-^ is a standard deviation of the i - t h regression coefficient. The multiple coefficient of determination (R ) is an important s t a t i s t i c which indicates that (R x 100) per cent of variation is explained by the regression. It is calculated as follows: Regression sum of squares R2 = Total sum of squares Square root of the multiple coefficient of determination is called the multiple correlation coefficient (R). It is a measure of the degree to which the dependent variable y is influenced by the m independent variables. The value ranges between the two extremes, zero and one. Because multiple regression analysis is a very operative st a t i s -t i c a l technique to detect which factor(s) is actually the most influential 211 on the development of vegetation, a number of workers have recently employed i t in order to analyse the relationships between plants and environment (Coile 1 9 5 2 , Rutter 1 9 5 5 , F r i t t s I 9 6 0 , Medin i 9 6 0 , Eis 1 9 6 2 , Patten 1 9 6 3 , Scott and Billings 1 9 6 U , Beil 1 9 6 6 , Mowbray and Oosting 1 9 6 8 , Wali 1 9 6 9 ) . It i s quite effective especially when a large number of factors are simul-taneously taken into the processes. One of the d i f f i c u l t i e s which might be encountered when the multi-ple regression analysis i s introduced into vegetation studies, is a problem of quantitative estimation and measurement of the vegetation which would be designated and processed as a dependent variable. Most of the studies have been based on a single species parameter such as site index (Eis 1 9 6 2 ) , annual radial growth of trees (Fritts i 9 6 0 ) , coverage of a specie's in a per-centage (Rutter 1 9 5 5 ) , importance value (Mowbray and Oosting 1 9 6 8 ), basal area and density (Beil 1 9 6 6 ), species significance (Wali 1969) and standing crop of a given species (Scott and Billings I 9 6 U ) . i i . "Likeliness value" as dependent variables In the present study, however, an attempt was made to evaluate vegetation as a whole, as much as possible on a quantitative base. For this purpose, "likeliness value" was devised and used. The "likeliness value" is a quantitavive assesment as to how much a stand (plot) is l i k e l y to be a member of a particular association, based on i t s f l o r i s t i c character. A plot which belongs to a certain association must possess element species of the association to a great extent, but, at the same time, the plot may con-tain a small number of species which belong essentially to other associations by chance. Thus, by evaluating quantitatively the element species of the association in the plot, the likeliness of the plot to be a member of the association would be numerically assessed, and simultaneously the l i k e l i -212 ness to be a member of other associations can be determined also by evalu-ating the element species of other associations. This is the basic idea underlying the "likeliness value". Thus, the element species of each association, except for the moss association, were determined. From the components of an association, four or five species were selected so that they composed a set of element species of the association. Such species which had strong exclusiveness to the association and a high dominancy in i t but not in other associations, were especially prefered. These species were chosen only from the constituents of the Bg and C layers because they are more sensitive to environmental variation and more usable to distinguish the association than those of other layers. Although the quantitative characters of the species were more useful, the idea to select the element species was somewhat similar to that of the "characteristic species". Therefore, the selected species were i n c i -dentally also the members of the characteristic combination of species. The following are the sets of species selected as element species for the associations: for the Gaultheria shallon association (G): Gaultheria shallon Vaccinium parvifolium Linnaea borealis Chimaphila umbellata for the Achlys - Polystichum association (A-P): Achlys t r i p h y l l a Gymnocarpium dryopteris Polystichum munitum Ti a r e l l a t r i f o l i a t a Trientalis l a t i f o l i a 213 for the Oplopanax - Adiantum association (0-A): Oplopanax horridus Adiantum pedatum Athyrium filix-femina Galium triflorum for the Vaccinium alaskaense association (V): Vaccinium alaskaense Clintonia uniflora Cornus canadensis Rubus pedatus Streptopus roseus The likeliness value of a plot to each association is actually obtained by averageing the species significance (in Domin-Krajina scale) of the species in each set of respective association. Species significance (+) was counted as 0.5. If a plot does not contain any one of the species in a set of certain association, the likeliness value to the association then would be zero. The case of the maximum value could be 10, i f a l l the species in a set show species significance 10. In general, the more a plot is l i k e l y to be a member of an association, the larger the likeliness value would be. This idea, however, could not be applied to the moss association. Because the moss association was characterized by a strong dominancy of bryo-phytes such as Hylocomium splendens, Eurhynchium oreganum and Rhyt i di adelphus  loreus and any vascular plant was hardly found to be a dominant. Therefore, i t was almost impossible to assign any vascular plant as element species of the association. Moreover, i t was also d i f f i c u l t to employ the bryophytes as element species, since the bryophytes occured in any association more or less indiscriminately. 21k A completely different procedure, therefore, was applied to the moss association to calculate the likeliness value. The basic idea is this : the association i s rather characterized by the absence of these species which essentially represent oth