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Influence of slash burning on the establishment and initial growth of seedlings of Douglas-fir, western.. Jablánczy, Alexander 1964

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INFLUENCE OF SLASH BURNING ON THE ESTABLISHMENT AND INITIAL GROWTH OF SEEDLINGS OF DOUGLAS-FIR, WESTERN HEMLOCK, AND WESTERN REDCEDAR A study of the effect of simulated slash burn on s o i l blocks from some sites of the Coastal Western Hemlock Zone by ALEXANDER JABLANCZY For. Eng., Technical College of Prague, 1932 Cand. of Science, Hungarian Academy of Science, Budapest, 1954 Professor of Silviculture, Sopron University, 1954  A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy i n the Department of Biology and Botany  We accept this thesis as conforming to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA  1964  In the  presenting  r e q u i r e m e n t s f o r an  British  mission  for reference  for extensive  p u r p o s e s may  be  of  by  w i t h o u t my  written  Department  of B i o l o g y  M  a  E  C  h  1 5  '  1  9  6  k  I further  Head o f my  i s understood  Botany Columbia,  fulfilment  of  University  of  s h a l l make i t f r e e l y  this thesis  permission.  and  the  Library  agree for  that  or  c o p y i n g or  shall  per-  scholarly  Department  that  for f i n a n c i a l gain  The U n i v e r s i t y o f B r i t i s h V a n c o u v e r 8 , Canada. Date  study.  the  in partial  d e g r e e at  the  copying of  It  this thesis  that  and  granted  representatives.  cation  advanced  Columbia, I agree  available  his  this thesis  not  be  by publi-  allowed  ii ABSTRACT Laboratory and greenhouse experiments were carried out with controlled burning and with seedling growth correlated to s o i l chemical changes. The surface of s o i l blocks from three sites of the Coastal Western Hemlock Zone were burned at two intensities and planted separately with seeds of Douglas-fir, western hemlock, and western redcedar. Growth data were recorded periodically and dry weights of the seedling crops were obtained to determine treatment differences. The burning procedure showed the insulating and cooling effects of the vaporizing s o i l moisture. The burning slightly increased germination of Douglas-fir and western hemlock, generally promoted fungal population, and initiated different chemical changes i n the s o i l on each site.  Dry matter  production, for a l l species combined, varied with treatment for each site in the following decreasing order: Swordfern site - severely burned, moderately burned, unburned control;Moss site  - unburned control, moderately burned, severely burned;  Salal site  - moderately burned, unburned control, severely burned.  Comparisons of dry matter production on control blocks with that in nature indicated that the removal of blocks from the natural environment had significantly changed the original conditions.  In consequence, new  a r t i f i c i a l sites were created. Consistent evidence of the rhizosphere effect was produced on s o i l pH by seedlings, especially by Douglas-fir.  Dormancy was successfully  broken i n a l l plants and there was evidence of different responses i n photoperiodism with each species.  iii The highest dry matter production was directly related to increased s o i l pH, to increased partial cation saturation, and to increased concentration of available phosphorus but to a decreased cation exchange capacity. Cation exchange capacity was inversely related to the availability of nutrients.  Decrease of cation exchange capacity proved to be a beneficial  effect of f i r e .  In this experiment, where the ash was not supplied as usual  in a slash burn, the increased base saturation resulted from the decreased cation exchange capacity. As compared with field samples in August 1959, total nitrogen was lower in a l l blocks in June 1960.  Nitrogen increased in the following year  in a l l variants of the Swordfern site and somewhat in unburned control blocks of the Moss and Salal sites. The Swordfern site benefited from burning by accelerated mineralization, which substituted for the deprived seepage. to this habitat.  Fire caused the least damage  The Moss site suffered heavily by burning, which reduced  humus, the main source of nutrition.  The unburned blocks were benefited  by fast decomposition of humus in the greenhouse.  The Salal site's thick  raw humus benefited from moderate burn, which removed part of the humus and acted as a f e r t i l i z e r on the remainder.  Severe burning was most harm-  ful on this site by the destruction of the large part of humus. Rich soils, usually with seepage water, are less damaged by fire than poor soils with strong drainage.  It is mainly because in rich soils  organic matter is at least partly incorporated into the mineral horizon and acts readily after fire especially for nitrogen supply.  V. J . Krajina  ACKNOWLEDGEMENTS  Of the many people who assisted i n this study, Dr. V. J. Krajina i s most deserving of special appreciation. The experimenter i s also thankf u l to the National Research Council of Canada (N.R.C. Grant No. T-92) and to the Senate of the University of British Columbia for financial aid. The following agencies generously allowed the help of their staff and f a c i l i t i e s for the tasks of sample collection, seed preparation, burning, growing the seedlings, drying and weighing the crop and analysis of s o i l samples: British Columbia Research Council, Vancouver, B. C , for electronic equipment; Department of Biology and Botany, U. B. G., for greenhouse premises and laboratory; Faculty of Forestry, U. B. C , Research Forest i n Haney, B. C. and seed laboratory; Department of Metallurgical Engineering, U. B. C , laboratory; Canada Department of Agriculture, Agricultural Research Station, Vancouver, B. C , S o i l Laboratory; Canada Department of Forestry, Forest Products Laboratory, Vancouver, B. C. The author i s indebted for many helpful suggestions to a l l members of the Candidates Committee and to the professors who i n some way contributed throughout the three-year period: Dr. T. M. C. Taylor, Dr. V. J . Krajina, Dr. G. S. Allen, Dr. R. J. Bandoni, Dr. J . E. Bier, Dr. J. D. Chapman, Dr. J. S. Clark, Dr. P. G. Haddock, Dr. C. A. Rowles, Dr. J . H. G. Smith and Dr. D. J . Wort. Respectful thanks are due, for help i n developing the burning method, to Messrs. J . Gerencse'r and M. Salamon; the latter also assisted i n drying and weighing procedures. The writer would like to acknowledge the technical help i n s o i l analyses by Mr. G. Leskd and i n s t a t i s t i c a l work by Messrs. J. Sod's and L. Magasi, and l a s t l y the faithful performance of tiresome f i e l d and greenhouse work by his son, A. Jablahczy, J r . A c r i t i c a l review of the original text by Drs. V. J . Krajina, T. M. C. Taylor and W. B. Schofield was a great help to the writer. Further suggestions for organization of the text, by Mr. E. B. Peterson, are also gratefully acknowledged.  iv  CONTENTS  Chapter I.  P a  1 3 8  EXPERIMENTAL MATERIAL AND METHODS Area of c o l l e c t i o n Sample b l o c k s Seed B u r n i n g t h e sample b l o c k s Sowing t h e t r e e seed M i c r o - c l i m a t o l o g i c a l c o n d i t i o n s and i r r i g a t i o n Seedling population B r e a k i n g o f dormancy S e e d l i n g growth and d r y m a t t e r p r o d u c t i o n Accompanied v e g e t a t i o n on b l o c k s S e e d l i n g s from f i e l d S o i l chemical analyses * Note on s o i l p h y s i c a l p r o p e r t i e s Photographs and s e e d l i n g c o l l e c t i o n s S t a t i s t i c a l analysis  III.  e  INTRODUCTION H i s t o r i c a l background Views on t h e e f f e c t o f f i r e O b j e c t i v e s o f t h e experiment  II  K  «  9 16 18 18 27 28 29 30 31 33 34 34 35 36 36  RESULTS AND DISCUSSION Changes i n c o m p o s i t i o n o f t h e accompanied v e g e t a t i o n Establishment of seedlings Survival of seedlings F i r s t s p r i n g growth ; Summer growth Autumn growth S t i m u l a t e d w i n t e r growth Second s p r i n g growth S i z e and w e i g h t o f h a r v e s t e d s e e d l i n g s Phases o f s e e d l i n g growth Changes o f s i t e s by m o d i f i e d c o n d i t i o n s Chemical s o i l p r o p e r t i e s E f f e c t o f c h e m i c a l s o i l p r o p e r t i e s on d r y m a t t e r production Discussion of f i n a l r e s u l t s  37 41 45 47 52 56 59 60 61 64 69 71 86 89  V  Chapter IV.  Page SUMMARY AND CONCLUSIONS E f f e c t of burning Changes i n accompanied v e g e t a t i o n Seedling establishment S e e d l i n g growth Chemical s o i l p r o p e r t i e s A d d i t i o n a l observations Major c o n c l u s i o n s BIBLIOGRAPHY  90 92 93 94 98 100 103 104  APPENDIX 1. II. III. IV. V.  Tables, I t o XXXII 112 S t a t i s t i c a l analysis 158 Accompanied v e g e t a t i o n 165 Methods o f s o i l c h e m i c a l a n a l y s e s .............. 181 P l a t e s , I t o XXX 190  to f o l l o w  page  CHART OF SYMBOLS AND ABBREVIATIONS USED IN FIGURES I AND TABLES]  SITE I - SW S T ^ SWORDFERN II -  SITE  M ST - MOSS SITE  ..nr- SL ST - S A L A L SITE TREE SPECIES D  -  DOUGLAS - FIR •  H  -  WESTERN HEMLOCK  C  -  WESTERN REDCEDAR  BURNING RATE TREATMENT S -  SEVERELY BURNED  M •  MODERATELY BURNED  U -  UNBURNED  CONTROL  SEEDLING GROWTH ON EACH BLOCK AND AVERAGE FOR A GROUP OF FOUR BLOCKS  M  v  vi LIST OF FIGURES  Number  To follow page  1.  Location of the experiment  9  2.  Monthly temperatures and humidity at two meteorological stations i n the Haney Forest  •  10  3.  Soil block i n metal container  16  4.  Layout of seedling blocks and s o i l blocks i n the greenhouse ....  28  5.  Distribution of a r t i f i c i a l light for breaking dormancy  28  6.  Weekly temperatures i n the greenhouse during the experiment ....  29  7.  Weekly relative humidity i n the greenhouse during the experiment  ""8. 9. 10. 11.  •  •  29 30  March of temperature during a slash burn March of temperature during laboratory burning for the block surface • March of temperature during laboratory burning for a depth of two inches March of temperature during laboratory burning for a depth of four inches  •  .....  30 30 30  12.  Standard petri dish germination tests  41  13.  Relative germination on seedling blocks, May 5, I960  42  14.  Survival of four-week-old germinants, May 15, I960  45  15.  Height of ten-week-old seedlings, July 1, I960  48  16.  Height of four-month-old seedlings, August 20, I960  53  17.  Height of eight-month-old seedlings, December 30, I960  56  18.  Height of twelve-month-old seedlings at the end of the stimulated growth, April 20, 1961 Height of fourteen-month-old seedlings after the second spring growth, June 25, 1961  19.  59 60  vii  20.1.  Swordfern site. Length of shoots and roots on removed seedlings, July 8, 1961  61  20.2.  Moss site. Length of shoots and roots on removed seedlings, July 8, 1961  61  20.3.  Salal site. Length of shoots and roots on removed seedlings, July 8, 1961  61  21.  Group averages of shoot- and root-lengths by twelve seedlings i n each variant  61  22.1.  Swordfern site. Total dry shoot- and root-weights of three seedlings removed from each block  6l  22.2.  Moss site. Total dry shoot- and root-weights of removed seedlings  61  22.3.  Salal site.  Total dry shoot- and root-weights of removed  seedlings  • 61  23.  Summary of site averages for shoot- and root-weights  24.  Comparison of site and weight of seedlings from unburn ed cont r o l blocks and of natural seedlings i n the sampled area. 61 Swordfern site. Periodic growth of seedlings i n the  25.1.  61  • 64  experiment 25.2.  Moss site.  Periodic growth of seedlings i n the experiment ... 64  25.3.  Salal site.  Periodic growth of seedlings i n the experiment .. 64  26.  Average of periodic growth of the three species of each site.*  Relative dry weight production for each species i n each treatment on a l l sites 28,1a. Swordfern site. Average, entire block. Changes of some  64  27.  chemical properties i n the s o i l samples.... 28,1b. Swordfern site.  Average for one-inch surface layer  64 85 85  28,2a. Moss site.  Average for entire block...  85  28,2b. Moss site.  Average for one-inch surface layer  85  28,3a. Salal site.  Average for entire block  85  28,3b. Salal site.  Average for one-inch surface layer.  85  viii LIST OF TABLES Number I. II. III. IV.  Page Characteristics of three places of sample block collection  113  Morphology of soils i n sample collection ditches  114  Permanent numbers of growth sample blocks and s o i l sample blocks  115  Highest temperatures recorded by some authors during the burning  V. VI.  116  Burning characteristics  117  Productivity of growth blocks plotted against the burning rate and remains on surface  118  VII.  Water used for irrigation and precipitation at the sample area .. 119  VIII.  Adjustment per cent of germination on groups of four blocks ..... 120  IX. X. XI. XII. XIII. XIV. XV.  Average values of seedling development on each group  121  Fresh weight for each group  122  Water content of seedlings  123  Shoot/Root ratio of seedlings  124  Size of two-year-old wild seedlings  125  Weight of twelve wild seedlings and their water content  126  Dry weight of twelve seedlings from unburned sample blocks and from the f i e l d  XVI. XVII. XVIII. XIX. XX.  Seasonal changes of growth i n blocks.  127 (Three sites)  128  Field and block samples  131  Soil pH values of f i e l d and block samples  134  Deviation of s o i l pH i n growth blocks and corresponding sample blocks Determination of cation exchange capacity. Example  137 139  ix  Number  Page  XXI.  Magnesium and calcium determination.  Example  140  XXII.  Calcium and potassium determination.  Example  141  XXIII. XXIV. XXV. XXVI.  Phosphorus determination.  Example  Organic matter determination. Nitrogen determination.  Example  Example  XXVIII.  Analysis of charcoal, Ae layer and concretion material  XXX. XXXI. XXXII.  144  145 148  Chemical properties of unburned blocks and the differences of these from burned blocks i n I960 and 1961  XXIX.  143  Exchangeable cations and some other nutrients, surface layer and entire sample block  XXVII.  142  Changes i n chemical characteristics from I960 to 1961 Changes i n phosphorus content as related to s o i l pH and the productivity Values and per cent changes of chemical s o i l properties which are directly related to the productivity of corresponding seedling blocks. (Three sites) Statistical significance between treatments for average size of each seedling and for dry matter production of each seedling block  149 151 152 154 157  LIST OF PLATES Number I. II. Ill, IV. V. VI. VII. VIII. IX.  Ditches for sample block collection. Unburned sample blocks i n the greenhouse, March, I960. Burning process i n the Metallurgical Laboratory. Burned surface of Swordfern site samples. Burned surface of Moss site samples. Burned surface of Swordfern site samples. Burned surface of Salal site samples. Four-week-old Douglas-fir seedlings before thinning. Six-week-old Douglas-fir seedlings after thinning.  X.  Four-week-old western hemlock seedlings on severely burned samples before thinning.  XI.  Six-week-old western hemlock seedlings on unburned control samples before thinning.  XII.  Six-week-old western redcedar seedlings before thinning on severely burned samples.  XIII. XIV. XV. XVI. XVII. XVIII.  Cross-section of severely burned analyzed sample blocks. Cross-section of moderately burned sample blocks. Cross-section of unburned control analyzed sample blocks. Cross-section of analyzed Salal site sample blocks. One-season-old seedlings from the experiment and from the sample areas at Haney. Swordfern site samples with average growth of seedlings from each group at the end of stimulated early growth.  XIX.  Moss site samples with average growth of seedlings.  XX.  Salal site samples with average growth of seedlings.  xi  Number XXI.  XXII, XXIII.  XXIV. XXV. XXVI. XXVII. XXVIII.  Part of the experimental lay-out and a close-up of an unburned Swordfern sample with chlorotic Douglas-fir seedlings. Chlorotic Douglas-fir seedling from the severely burned Moss site sample. Purple-tinted western redcedar seedlings from the severely burned Salal site sample, and from the unburned control Swordfern site sample. Chlorotic western redcedar seedlings on the severely burned Moss site sample and unburned Swordfern site sample. Swordfern site.  Two blocks from each treatment, June 3 0 , 1961.  Moss site. Salal site. Severely burned sample blocks.  Two blocks from each site.  XXIX.  Moderately burned sample blocks.  XXX.  Unburned control sample blocks.  CHAPTER  O N E-  INTRODUCTION  Historical Background Holbrook's book, Burning an Empire  (1943),  is an excellent commen-  tary of reasons why and how the attitude of North Americans toward forested land has changed.  The author has this to say:  "There were three basic fallacies that resulted i n the economic difficulties . . . f i r s t , that the virgin timber could never be exhausted. Second, . . . that the cut-over lands would be taken up, every last acre, i n a tremendous agricultural development that would produce richer returns than the original timber crop. Third, . . . was the firmly held belief, . . . that fire running through second growth timber was of no moment: the old brush f i r e fallacy." Economic development i n North America, accompanied with an even more rapid rise of research i n natural sciences, brought about a better understanding of forest resources and their destructive menace, the f i r e . Greeley wrote i n his foreword to Holbrook's book: "We are indebted to St. Holbrook for this vivid writing of a part of our history which i s understood by few Americans and unknown to most of them." He further added that "the attitude of the pioneer toward woods burning was doubtless inevitable", and later, " . . . the woods were fired to clear land for farming; to create pasture". Greeley summarized his points i n the proverb, "prevention of forest fires i s three-fourths of forestry", and the recognition of the destructive power of forest fires soon resulted i n an unfavorable attitude towards i t .  This attitude was soon supported by a number of scientific  results. Recent discoveries dealing with the changes i n forest vegetation revealed a significant role of f i r e .  The role of fire was recognized as  - 2 not necessarily destructive but certainly determinative. The fire hazard problems of cut-over areas and the difficulties i n reforesting such lands have encouraged the use of controlled f i r e . One may generalize now, that though an uncontrolled forest fire i s disastrous; controlled slash burning i s a useful tool for forest management i n two ways.  Primarily, the prevention or reduction of fire hazard, and  secondarily the creation of conditions appropriate for the establishment of future stands, are the two purposes of deliberate and controlled burning applied to cut-over lands. The amalgamation of practical results i n forestry with the findings of research workers has provided further knowledge i n recent decades. are, however, significant discrepancies i n opinions.  There  The available publica-  tions exceed fifteen hundred, a large proportion of which has been written during the last two decades. The two most comprehensive books on the subject, namely:  Forest  Fire; Control and Use, by Davis (1959); and Ecological Effects of Forest Fires, by I . F . and C. E. Ahlgren (i960), were not yet available during the course of this experiment. The present study was aimed primarily at the problem of slash burning, but the survey of literature could not be confined only to the reported slash burn observations or experiments.  The number of such works i s small.  Burning of forest debris may be considered as a simulated forest fire since i t s effects are similar to that of a wild f i r e . studies on forest fires was also u t i l i z e d .  Knowledge gained from  -3 Views on the Effect of Fire Three groups of authors can be distinguished according to their opinion on the effect of fire on forest site. 1.  A general harmfulness i s expressed by many workers.  Show and  Kotok (1924) believed that California forests had lost their productive capacity by repeated fires. decreases s o i l f e r t i l i t y .  Worley (1933) stated that i n New Zealand fire Isaac and Hopkins (1937) wrote:  "The harmful effects of the ordinary slash fire more than outweigh any beneficial effects i t may have on the productivity of Douglas-fir forest s o i l . " Crosbie (1940) called suggestions for burning "dangerous", and Hansen (1942) also stressed only the harmful aspects of forest f i r e s . Hawley and Smith (1954) expressed a general opinion i n their handbook on silviculture, "very hot fires are always harmful".  Lutz and Chandler  (1949) suggested that "the majority of fires must be regarded as harmful, to the soil".  Westveld (1949) emphasized the same opinion. Candy (1951) pointed out that fire i s a cause of failure for  conifers except the jack pine - subalpine type.  He believed that fires i n  Western Ontario and the Maritimes introduced intolerant hardwoods. Krajina (1958) claimeian overall harmfulness of any form of burning in forests and urged that, "foresters should do everything possible to stop slash burning". He subsequently recommended a study of this problem on ecological basis to distinguish the degree of this harmfulness.  His student,  Mueller-Dombois (1959) observed that higher stocking occurred on the unburned plots than on the burned ones. 2.  The general usefulness of forest fires, at least i n controlled  form, is supported by more workers than the opposite standpoint.  - 4 The necessary removal of accumulated raw humus i s one of the main concerns of many authors.  Lovejoy (1920), Muller (1929), Suchting (1929) and  Uggla (1958a,b) accepted the importance of fire as a reducer and activator of raw humus.  Uggla expressed his opinion as follows: " . . . the ashes and carbonized remains and the l i t t e r form a thin cover upon the undamaged humus layer. The alkalis of the ash can be absorbed by the humus cover i n an easily acceptable form, the nitrogen metabolism i s i n creased, and the conditions for most micro-organisms are ameliorated . . . . The root competition is reduced. The temperature at the surface w i l l rise on account of the increased a b i l i t y of heat absorption of the black humus cover, which favours the germination of seeds." Biswell (1958), who changed his mind on the problem, accepted  prescribed burning as "useful and essential" i n forestry of the Southern United States.  J . Viands et a l . (1955) quoted 28 authors with a positive  approach towards controlled burning. Similarly, the Ahlgrens (i960) l i s t five workers advocating the general usefulness of fire for trees and 19 who were for  i t s beneficial effect on herbaceous plants. Chaiken (1949), Lotti and Culley (1951), Lotti (1956), Wenger and  Trousdell (1957), Lutz (1956) should be listed i n favor of slash burn. Allen (1954) accepted the use of controlled burning i n order "to maintain our Douglas-fir forests as nature did". Weaver (1955) wrote:  "Fire  under control i s one of the most useful servants of c i v i l i z e d man." Tamm (1950) expressed and elaborated his opinion this way: "From Hesselman's intensive investigations, i t has been proved that a forest fire i n numerous instances has a strongly activating effect on a mor covering. In particular, nitrogen conversion sets going actively and usually leads to n i t r i f i c a t i o n . This process seems to benefit the early development of the young conifer seedlings but i s by no means an essential factor for that. Parallel with the nitrogen conversion, a general decomposition process goes onj i t i s quite clear that a large part at least of the organic material,  which has been l a i d down i n a form which i s relatively d i f f i c u l t to break up (H-layer), again undergoes conversion." The "Sloan Report" (1957) accepted controlled burning as a method for the forest management i n British Columbia.  The Pacific Northwest Experi-  ment Station of the United States (1957), stated that "slash burn does not appreciably damage chemical, physical or biological properties of the soil". It noted that only a very small proportion of the burned areas used to be severely burned, and that such controlled burn greatly reduces fire hazard. Schmidt (1957) and Davis (1959) stressed that the large part of the present Douglas-fir forests on the Pacific Coast originated following wild fires and i t s absence on some places "can be attributed to a low fire frequency" (Schmidt).  Gibson (1958) wrote about controlled burning on the  Pacific Coast that i t "may be compared to medication".  Garman (1955)  supports the same view. The above-quoted opinions were not usually generalized by their authors, but were expressed i n connection with some particular circumstances or regions.  Nevertheless, these authors did not emphasize local or ecological  influences. 3.  The third group are those with a specific approach to the prob-  lem i n which the investigator avoids any generalizations and tries to explain the effects as a result of different circumstances.  It i s noticeable that  the large majority of those who employ this approach, correlates the severity of burning with the ecological conditions. Stobbe (1940) objected to burning, but stated that "on i l l drained soils, burning seldom i s severe enough to cause great damage to the soil". He added that fire i n these circumstances w i l l improve physical conditions  - 6  of the s o i l . Tamm (1950) found burning harmful on poor, sandy soils or i n cases of the absence of immediate regeneration, but accepted i t s benefit on soils of better quality, where the risks of deterioration of the humus are less and the minerals, by their weathering, can deliver more nutrient substances to l i v i n g organisms. Allen (1953) accepted that intense burnings deplete the s o i l , but moderate burn i s "not practically harmful".  Tourney and Korstian (1956)  stated that controlled burning i s a "constructive agent" but the uncontrolled i s "always harmful".  Garman ( 1 9 5 5 ) , Viands and Biswell ( 1 9 5 5 ) , Chrosciewich  ( 1 9 5 9 ) , Gibson ( 1 9 5 8 ) , Metz et a l . ( 1 9 6 1 ) , Morris (1958) and many others expressed similar opinions on the changing effects of forest fires and slash burns. Hawley and Smith (1954) stated that "the most significant objection i s based on psychological grounds".  The same book emphasizes the importance  of slash burning as a useful means of reducing fire hazard. Bennett ( i 9 6 0 ) who i s otherwise i n favor of slash burning, admitted that certain silvicultural and s o i l losses may result. Davis (1959) cautiously accepted burning with many conditions, which may be summarized by the following three points:  (l) Slash burn i s a  quick means of freeing the ground of large quantities of forest debris; (2) Slash burn creates heat effects to vegetation, fauna and the s o i l , more of which i s k i l l e d than consumed; ( 3 ) Slash produces residual mineral products that may have chemical effects upon the s o i l . points by the following statement:  He explains his  "Through changes induced i n micro-climate and vegetation, fire has major effects i n the interception, evaporation, transpiration, storage^ and movement of water i n forest stands and soils." The general idea i s expressed shortly this way; each situation must be specifically appreciated.  He considers clear cutting of Douglas-fir as an  excellent example of the inevitable application of slash burn. The Ahlgrens (i960) summarized the opinion of many authors as follows: "It i s impossible to draw many general conclusions as to the ecological effects of f i r e . Rather, each combination of region, climate, forest tree association, s o i l type, and plant species must be considered individually." Krajina has expressed his views on ecological effects of burning upon the forest s o i l as follows: "An unburned s o i l has normally a humus layer, allowing a slow water percolation, holding necessary nutrients for plant growth, and continuously controlling s o i l temperature below i t . The nutrients are slowly released to the plants through humus decomposition speeded by solar radiation i n clear-cut areas. On a burned site the humus i s reduced to ash, and available nitrogen compounds are reduced or removed u n t i l replaced by bacteria. Bared s o i l permits rapid water run-off and s o i l erosion. Blackened s o i l surface absorbs intense solar radiation and limits the success of seedling survival. In many cases site quality i s reduced either for a short or long period of time. As a rule burning affects better forest sites to a lesser degree than poorer sites. If slash accumulation i s great, spot slash burning may be necessary," and concludes: "Original site quality i s more easily perpetuated on unburned sites, i n the mesothermal climates of the Coastal Western Hemlock and Coastal Douglas-fir Zones, where humus i s usually under permanent decomposition."  Objectives of the Experiment The objective of this study was to correlate the regulated burning process with site conditions according to ecological classification.  This  objective was pursued through the examination of the effect of two intensities of simulated slash burning on germination, survival, growth, and crop of seedlings of Douglas-fir, western hemlock and western redcedar, on three sites of the Coastal Western Hemlock Zone. The direct purpose of the experiment was to correlate dry matter production on each site to the intensity of burning, and to interpret these correlations with the chemical properties of the corresponding s o i l samples.  - 9 CHAPTER TWO - EXPERIMENTAL MATERIAL AND METHODS Area of Collection The area of collection l i e s i n the University of British Columbia Research Forest, i n the foothills of the Coast Mountains southeast of Pitt Lake and 35 miles east of the City of Vancouver (Figure l ) .  The three plots  used for sample collection are at 23°00' West Longitude and 49°20' North Latitude. The portion of the Forest that was involved i n 'this work was destroyed by a fire i n 1868 and has since regenerated to mixed Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii). western hemlock (Tsuga heterophylla (Raf.) Sarg.), and western redcedar (Thuja plicata Donn.) forests (Griffith, I960). The area occurs i n the Coastal Western Hemlock Zone (Krajina, 1959), in which the most productive trees are:  Pseudotsuga menziesii var.  menziesii, Tsuga heterophylla. Thuja plicata, Picea sitchensis, and Abies amabilis.  The two last species do not occur in plots selected for this  experiment. The topography of the area i s rugged with numerous rock outcrops. The s o i l i s of glacial t i l l origin and of a sandy-loam texture, varying in depth from a few inches of organic s o i l , to more than three feet of depth of brown podzolic forest s o i l s . A l l three places selected for the collection of sample s o i l blocks are located nearby experimental clear-cut areas where reforestation experiments are performed by the Faculty of Forestry of the University of British Columbia. Soils and plant communities of the three localities have been  //loonlTN  Blaney L  2000 FEET  F I G U R E 1.  U-  U.B.C.  - SAMPLE  F-  HANEY  - METEOR.STAT..  LOCATION O F T H E E X P E R I M E N T  PLOTS  A - U B C , VANCOUVER,BRITISH COLUMBIA  &  RESEARCH  FOREST HANEY, B.C. B S E E CHART O F  SYMBOLS  SAMPLED  PLOTS ( LILEI.JIN THE RESEARCH FOREST.  o a  - 10 studied and described recently by Lesko (1961) and Orloci (1961). tative data of the stands were recorded by Griffith (i960).  Represen-  Table I sum-  marizes the data, and Figure 2 gives information on current temperature and humidity. The following i s a general description of the three l o c a l i t i e s . The orthic Polystichum (Swordfern) plant community "Thu.jetc—  1.  Polysticheturn muniti" (Orloci 1961), i s the most productive type of the three.  This site i s supplied with seepage water and belongs to the "seepage  communities" i n the warm and dry subzone of the Coastal Western Hemlock Zone. The plant association of this site (designated as no. I) consists of the following species:  Pseudotsuga menziesii, Thu.ja plicata, Tsuga heterophylla.  Rubus spectabilis, Polystichum muniturn, Dryopteris austriaca. Tiarella t r i f o l i a t a , Galium triflorum, Plagiothecium undulatum, Mnium insigne. Mnium punctatum, Eurhynchium oreganum, Rhytidiadelphus loreus, and many other species. The soils of the Swordfern site, developed from glacial t i l l , are generally well aerated and the accumulation of organic remains i s restricted. The quickly decomposing l i t t e r , incorporated into the upper layer of mineral s o i l (A ), forms a mull-like moder about two inches thick. h  Almost a l l the  profiles of this type are underlain by a more or less impervious layer of compressed t i l l , which causes a beneficial retention of water i n the B horizon during the dry summer period. The new National System for Classification (N.S.S.C., I960) classified this type of s o i l as 4.38 gleyed Acid Brown Wooded (with some characteri s t i c s of a transition toward 4.58 gleyed Concretionary Brown Soils).  to f o l l o w  100  I I II MEAN HUMIDITY I  ADMINISTRATION BUILD. 90  J  60  j  70  J  II  III  page  I I  UJ  <> - 60 D_  ' 50  >2  AO  j  •••30 H  LOON LAKE  ui ui  I IIIIIII IIIII I  g 90 UJ  a  ui 80  a: 3  < 70 cc a.  I;ff0 j 50  J  AO  J  30 A Months Years |1960 F I G U R E 2.  MONTHLY T E M P E R A T U R E S  1961 A N D HUMIDITY  L O G I C A L S T A T I O N S IN T H E H A N E Y  AT TWO M E T E O R O -  FOREST.  10  - 11 2.  The Moss type, denoted as no. II i n the experiment, i s represented  by "Orthic Plagiothecium forest type" of the plant community called "Tsugetum heterophyllae plagiothecietosum undulati" (Orloci 196l).  This  community has a rich tree layer, a very simple herb layer, and a rich moss cover.  The component species are:  Tsuga heterophylla, Pseudotsuga  menziesii. Thu.ja plicata, Acer circinatum, Pteridium aquilinum, Plagiothecium undulatum. Eurhynchium oreganum, Hylocomium splendens and Rhytidiadelphus loreus. The coarse textured, deep s o i l i s covered with a moderately thick, black organic mor layer of decomposed debris and moss rhizoids.  The water  movement is good, due to the coarse-textured s o i l and a hardpan layer which often has a transitional orterde-layer, above i t . This s o i l i s classified as 3.31-Orthic Humic Podzol of the Humic Podzol Great S o i l Group (i960). 3.  The Salal site, designated as no. I l l , i s represented by the  Lithosolic Gaultheria forest type, "Pseudotsugeto-gaultherietum lithosolicum" (Orloci 196l).  shalloni  This site i s characteristic for the rocky  hilltops and steep slopes of the Coastal Western Hemlock Zone.  It has a  shallow organic s o i l , with l i t t l e or no mineral s o i l over the continuous diorite and quartz-diorite bedrock.  Some crevices are f i l l e d with fine  mineral s o i l that gives support to the larger trees. trees are spread on the rock surface.  The long roots of  Seepage along the surface of the rock  and the capacity of the moss and l i t t e r to preserve the moisture, result i n a f a i r moisture condition during the whole summer season. The plant community i s represented i n the tree layer by Pseudotsuga menziesii, Thu.ja plicata, Tsuga heterophylla, i n the lower layer  - 12 by the occurrence of dwarfed Gaultheria shallon; further species are Holodiscus discolor, Vaccinium parvifolium. Pteridium aquilinum, Eurhynchium oreganum, etc. This s o i l belongs to the Great Group -5*3 Lithosol (1958) and has been classified as Eluviated Acid Lithosol, nearest to 5.32 (Lesko 196l). The places of block collection are shown on Plate I and their s o i l morphology i s presented i n Table I I . 1.  A short description follows here.  The ditch for s o i l block collection i n the Swordfern type was  located on the eastern edge of UBC-Sample Plot No. S - l , on a west-facing slope of 15 per cent. The ground was covered by dense, luxurious 3-foot-tall vegetation of western swordfern, Polystichum muniturn, leaving small place to Athyrium filix-femina. Eurhynchium oreganum, Pteridium aquilinum. Blechnum spicant. Mnium insigne. Rhytidiadelphus loreus, Dryopteris austriaca. Plagiothecium undulatum, Galium triflorum, Viola orbiculata, Trientalis l a t i f o l i a , Tiarella t r i f o l i a t a , Epilobium angustifolium, Epilobium adenocaulon, Senecio vulgaris, Vaccinium parvifolium, Rubus v i t i f o l i u s , Rubus parviflorus, Rubus spectabilis, Rubus leucodermis, Cornus n u t t a l l i i , Acer circinatum. Sambucus pubens, Oplopanax horridus and Betula papyrifera. The broken crown canopy on the edge of the clear cut provided about sixty per cent cover. The stoniness was less than 10 per cent, and only a small part of i t emerged on the surface, being always covered by mosses.  The stones were  larger and more angular than those i n the Moss site. The very thin humus layer of organic debris showed rapid decomposition and incorporation into the thick dark brown granular A, layer with fine  transition to a frequent and distinct charcoal layer, apparently 80 to 90 years old.  Charcoal occurred either in coarse blocks of about 1 to 2 cubic  centimetres, or as disintegrated material which stained the  layer.  The  coherence and moisture here were least of the three sites at the time of collection. The s o i l i s very weakly laterized as indicated by the accumulation of reddish concretions i n the uppermost B-^ horizon and by SiOg coatings on coarse sand i n B^ horizon.  The reddish brown and yellowish gray layers of  the B horizon seldom form horizontal layers; they are often irregularly slanting, and both contain cobbles and easily disintegrating concretions. The upper brown part had more concretions and was more firmly cemented. The roots of trees uniformly occupied the whole profile.  They  seemed to extend horizontally i n the upper parts of the B layer. 2.  The s o i l sample blocks from the Moss site were excavated from the  vicinity of sample plot S-8, 25 yards southwest from the clear cut, under a stand with an 80 per cent crown closure.  Douglas-fir, 6 to 13 inches i n  diameter, western hemlock, 3 to 17 inches, and western redcedar, 3 to 8 inches, occupied the selected area, with a number of recently fallen, 3 - to 20-inch trunks of these species. The area was covered by the following mosses:  Plagiothecium  undulatum. Eurhynchium oreganum, Hylocomium splendens, Rhytidiadelphus loreus; from the ferns, only Polystichum muniturn was present and i n low vigor.  Scattered, small-size shrubs were represented by Gaultheria shallon.  Vaccinium parvifolium, V. alaskaense and Rubus v i t i f o l i u s .  The most common  dicotyledons were Pyrola asarifolia and Linnaea boreal i s .  Senecio vulgaris.  - 14 Senecio silvaticus and Epilobium adenocaulon were also present. Red mushrooms of the genus Russula and many yellow slimy fungi covered the area. Surface stones were moss covered, and those i n the s o i l were smaller and fewer but more rounded than those i n the Swordfern site. Under the continuous and luxuriant moss cover there was a one- to six-inch dark brown moss-rhizoid humus layer, containing the hidden l i t t e r and other organic remains. moss carpet.  There was no similar debris obvious on the living  The moss-covered raw humus layer contained a large proportion  of tree roots which were from one-half to one inch thick. occupied the uncemented parts of the B layer.  Fewer roots  The roots penetrated deeper  than i n the Swordfern site. Immediately under the humus layer, which was often mixed with 4 to 10 inches of red decayed remains of redcedar trunks, was a one-half-inch charcoal layer of lumps smaller than one cm. area was covered with such layer.  Twenty-five per cent of the  Fine powdery charcoal material was mixed  with the humus material on about 35 per cent of the whole area. The eluviated layer (A ) of the gray podzol material was found only g  on a small proportion of the excavated area.  It was present usually below  the charcoal layer or under the accumulation of decayed wood of redcedar. The thickness of the incoherent A layer seldom exceeded one-quarter inch, g  being usually only one-eighth inch. thickness of two inches.  On a few spots this layer reached a  The A layer occupied only 25 per cent of the area, g  much less than i t usually occurs i n this type (about 50$). The B horizon had two distinctly coloured components; an upper red and a lower yellowish-gray material.  Their boundaries were distinct, but  never regular i n depth.  Cemented concretions were present i n both, but much  more compacted i n the yellow layer, i n which the compactness often reached a hardpan-like coherence.  The red layer was sometimes absent.  The moisture i n the moss type was much more noticeable than i n the Swordfern site at the time of collection; this made the coloration of the fresh profile more striking. 3.  S o i l blocks were collected from the Salal site 15 yards southeast  from the clear cut, UBC-Sample Plot Ko. S-4, on a southeast slope of 25 per cent.  The area was surrounded on the south and east by an old stand.  Eight  living redcedar, 3 to 6 inches i n diameter, seven Douglas-fir, 4 to 8 inches, and four hemlock trees, 6 to 8 inches, were on the plot.  A 20-inch-  thick rotten western redcedar trunk occupied the middle of the area.  It was  densely covered with moss and yielded large amounts of disintegrating red decaying woody humus.  No slash or other disintegrating material was apparent  i n the continuous moss carpet of the following species:  Eurhynchium  oreganum, Hylocomium splendens, Rhytidiadelphus loreus and Rhytidiadelphus triquetrus.  A few seedlings of Betula papyrifera were found.  Gaultheria shallon occurred sporadically.  Dwarfed  Epilobium adenocaulon, Viola  orbiculata, Holodiscus discolor, and Hypocheris radicata completed this poor plant community. The shallow, predominantly organic s o i l of the area was lying on an irregular, mostly convex, smooth bedrock.  Under the 3 - to 9-inch organic  layer, mineral s o i l seldom over one-half inch i n thickness covered the hard, sometimes slightly weathered rock surface. The black, wet, sticky raw humus layer was covered by moss vegetation and f i l l e d with the root systems of trees.  Douglas-fir succeeded only  - 16 in depressions where the accumulation of the mineral s o i l was greater. No trees larger than 4 inches could otherwise develop on shallow mineral soil.  Douglas-fir i s dying out early i f i t cannot reach such mineral s o i l . In the past 80 years a new organic s o i l started to develop, and  has accumulated great amounts of organic nutrients.  The new experimental  clear cut i n 1951, however, shows the process of erosion and desiccation. The charcoal remains from the last forest fire formed a distinct half-inch layer on 75 per cent of the explored area immediately over the mineral s o i l , or mostly on the bedrock.  The disintegrated charcoal i s  mixed with raw humus. An eluviated layer (A ) was formed below the charcoal, on only g  about 25 per cent of the area, where the presence of mineral s o i l allowed such formation.  It never reached a thickness of one inch.  Despite the preceding dry summer period, during nighttime, the bare rock surface was moistened by the seepage water from the surrounding parts. Sample Blocks The t i n cans for holding the experimental soil-sample blocks measured 9 by 9 inches inside and were 14 inches t a l l .  The surface area of  a can measured 80 square inches and the volume was 1080 cubic inches (Figure 3).  Each can was provided with six drainage holes of one-quarter  inch diameter. The excavation of consistent prisms was impossible i n the Swordfern site and in many cases i n the Moss site. perfect blocks from the Salal site.  There was no difficulty to cut out  In those cases when the s o i l material  J to follow I  :  9in.  B  FIGURE 3.  SOIL BLOCK IN METAL CONTAINER A - SURFACE GRID PATTERN OF FIFTY SEEDS, . B - SIX HOLES AT THE BOTTOM FOR DRAINAGE AND TWO ON THE FRONT FOR MEASURING TEMPERATURE.  - 17  was friable, shallow prisms were put i n by two or three layers. 3 - to 4-inch layer was kept i n one piece i n every case.  The upper  The blocks were cut  out from the walls of a ditch 25 inches wide and 25 inches deep.  The blocks  were turned out on a board from which i t was slowly slipped into the cans. The working method had to be accommodated to the site and even to the minor variations of the s o i l consistency. From the Swordfern site, a 12-foot-long ditch was dug out.  From  the area of 80 square feet, 120 cu. f t . of s o i l was removed and 46 prisms were collected with an amount of 27 cu. f t . s o i l material. On the Moss site, a ditch 18 by 5 feet was opened with a total surface of 100 sq. f t . , and 200 cu. f t . of s o i l was removed, because of the great losses due to the presence of stones.  The 46 collected prisms measured  about 28 cu. f t . On the Salal site a 30 by 30 foot surface was piled off from the rock to get 48 blocks, which hardly f i l l e d half the depth of the cans.  Here  only 60 cu. f t . of s o i l was removed, and the collected amount was estimated as 15 cu. f t . This was the only place where earthworms were found in the course of the s o i l sample collection.  Lutz and Chandler (1946) stated that earth-  worms occur i n the range of 5 . 8 to 8 . 3 pH. In this case the pH of the mineral s o i l where two earthworms were found showed values 4 . 1 0 to 4 . 2 5 (Table XVIII,A). The forest floor, both the l i v i n g plants and the dead components, was handled with care so that a l l plants, including mosses, were i n a natural condition (Appendix III). For chemical analyses, s o i l samples were taken from a l l three  profiles down to the depth of collected prisms. Seed Seed was acquired from the area of sample blocks.  The cones were  collected i n the last week of September from about fifteen trees for each species. The cones were air-dried three weeks at room temperature and extracted and dewinged by hand.  For storage,stratification and germination  tests, thermostats of the laboratory of the Faculty of Forestry were used. For germination tests, Petri dishes with vermiculite were used for one hundred seeds for each species (Figure 12).  The final test on  April 8 was started simultaneously with the sowing on seedling blocks i n the greenhouse to furnish standard data for germination on blocks.  The previous  tests showed that stratification for 93 days changed the germination capacity as follows: Douglas-fir from an i n i t i a l 36% to 90% western hemlock from an i n i t i a l 75% to 68% western redcedar from an i n i t i a l 78% to 28$ The test i n wood-ash indicated an indifferent effect, +2.6% on Douglas-fir; -48.6$ reduction on hemlock; and -82.2% on redcedar. Burning the Sample Blocks Burning with i t s results i s discussed i n this section i n detail. The regulation of burning was studied merely to learn how to produce two grades of uniformly repeatable burning for each site with equivalent effects. The literature on burning could not give proper information for delimitation and for controlling the burning rates.  The adjectives "severe",  - 19 "moderate", and "light" are used without strict distinctions (Table TV).  From  the three authors who distinguished burning rates by the effect on forest floor, only Bentley and Fenner related these categories to temperature conditions.  (Tarrant 1956a; Morris 1958; Bentley and Fenner 1958).  Only two  authors were found who recorded time i n their observations (Heyward 1938; Uggla 1957). It was necessary to decide:  (l) what intensity and duration of  fire to apply; (2) what source of heat to use; and (3) how to ensure the uniformity of burning on a large number of replicas. To provide some experience, a routine slash burning was visited by the experimenter on September 13, 1959. follows.).  (A description of the process  A slash burn was i n progress on a clear-cut area, at the  University Research Forest i n Haney, along the eastern road connecting the Administration Building with Loon Lake.  The air temperature was 55-60°F;  the humidity 60 per cent; the sky was clear and afternoon cloudy.  The forest  floor was moist from the previous week's precipitation. The area of the three-year-old clear cut was covered with the Swordfern and the Skunk cabbage plant communities.  More than five-foot-tall vege-  tation of Epilobium angustifolium, Rubus parviflorus, R. speetabilis. R. leucodermis, Sambucus pubens, and Acer circinatum covered 50 per cent of the area. Three-quarters of the area was covered with remains of the removed stand, forming slash about 2 to 4 feet high, and i n some places forming piles as high as 10 feet.  By volume, half of the fuel material was larger than 4  inches i n diameter, up to a thickness of 20 inches.  On the two acres of  clear cut to be burned on that day, ten cords of fuel was estimated.  This  - 20 material had been piled into thirty piles of a diameter of about 20 feet and height about 5 feet. piles.  Twenty-five per cent of the area was covered by slash  The piles were located near old stumps, where the accumulation of  organic material was the greatest, exceeding 10 inches. A crew of ten men, led by a forester, successively built up the piles and ignited them, five to eight at once, and cleaned up a 60-foot-wide insulating belt along the edge of the adjoining 30-year-old Douglas-fir stand. After two hours of preparation, the f i r s t ignition started at 10 A.M., and the last ended at 4:30 P.M.  Before the ignition one gallon of crude o i l was  poured on the heap of slash. The burning was rapid and reached i t s peak of flame intensity i n one or two minutes.  The flames exceeded 15 - 20 feet.  The heavy burning  went on for 30 to 45 minutes, u n t i l the pile collapsed, to start the second phase of glowing combustion.  This less rapid stage lasted from twenty  minutes to hours or even days under the ash and charcoal. The burned area from the previous day s t i l l showed glowing embers. Half the humus layer was destroyed.  The ash mostly from wood material made  one-half to one-inch layers, on 25 per cent of the whole area. The forest floor was examined i n a few places about 10 - 15 minutes after the end of the "high flaming phase".  Three inches under the glowing  fuel, protected by heavy ash, the moist humus could be touched by bare hand. This layer had temperature below 120-130°F (50-55°C). The burning consumed a l l fine slash.  It left only about two-thirds  of the thick wood and destroyed about one inch of the humus, on 30 per cent of the area. the area.  Aerial organs of the living vegetation were k i l l e d on half of  - 21  In order to produce distinguishable results on sample blocks, two grades of temperature were chosen for the experiment.  For the peak of the  severe burn 2000°F (1100°C) was chosen, and for the moderate a temperature of 1200°F (650°C).  These temperatures were measured 1 cm. beneath the surface.  For duration, thirty minutes was chosen for severe burning and fifteen minutes for moderate burning. A control in calculation of rates of burning was given by the destruction of organic layer and by changes i n the mineral s o i l (Tarrant 1956a; Morris 1958; Bentley and Fenner 1 9 5 8 ) .  The severe burn was meant to destroy  most of the organic material and had some effect on the mineral s o i l particles.  The moderate burn destroyed only a part of the humus and did not  affect the mineral s o i l . After the cans of the s o i l blocks were permanently marked with numbers, 84 of them were randomly selected for burning; 42 for severe and 42 for moderate burn; 42 remained as unburned controls.  Fourteen from each  site type were equally treated; 12 for seedlings and 2 for s o i l analysis (Table III). To imitate the routine practice, applied for controlled burning in B. C , each block was watered with an equivalent to one inch of precipitation.  One inch of precipitation means here 80 cu. i n . of water, which  equals 1 . 3 8 quarts of d i s t i l l e d water ( 1 . 3 1 l i t e r ) for each block. Three attempts were made i n 1959 to produce controllable heat. F i r s t , 250-watt incandescent, infra-red bulbs were used i n a four-unit set. A maximum temperature of 1000°F (538°C) was reached i n one hour from a distance of one inch.  This insufficient method had to be abandoned.  A Kerokill flame-thrower weedkiller, heated with kerosene, was also  - 22 tried.  This instrument failed because of i t s irregularity. A natural gas burner i n the U. B. C. Metallurgical Laboratory proved  to be most reliable.  This burner, regulated with an electric fan, was able to  produce temperatures up to 4000°F.  It produced the required effect from a  distance of eleven inches for the severe burn, and from fifteen inches for the moderate burn.  The heating capacity of the natural gas was often fluctuating,  however, by as much as l200°F (93°C). The burning of the 84 blocks was carried out from February 27 to March 27, I960 (Plate - III). For measuring temperature, thermo-couple gauges were used with an electronic Leeds & Northrup Co. potentiometer.  For the upper measurements i n  the s o i l surface, Chromel-Alumel wire, Type K, was used, suitable for a range of 600°F (3l6°C) to 2300°F (1240°C).  For measurements taken at depths of 2  1  and 4 inches below the s o i l surface, Iron-Constantan wire, Type J , was employed, suitable up to 800°F (427°C). fibreglass insulation.  1  Both types of wires had varnished  A few mercury thermometers were also used i n lower  regions, where the temperature did not exceed 300°F (149°C). The metal can was set on a brick base and coated with metallurgical furnace bricks extending a few inches over the upper edge of the can. To protect the metal from the heat effect, a protective coat was applied.  Four  one-quarter-inch asbestos sheets, four-inches-wide matching the 9-inch length of the can, were driven between the metal wall and the s o i l block.  Similar  sheets of asbestos were used on the top of the brick coat and on the stand to A change i n temperature of 5°F (2.78°C) corresponds to 0.100 m i l l i v o l t in Chromel-Alumel thermo-couple and to 0.150 m i l l i v o l t i n Iron-Constantan. 1  support thermo-couple gauges, and to facilitate handling. Three pairs of thermo-couples were installed:  two Chromel-Alumel  wires on the surface; two Iron-Constantan wires, two inches under the surface; and two identical to the previous at four inches below the surface. The two sensors i n each pair were located 3.5 inches apart at the same l e v e l . The two sensors on the surface were enclosed i n 14-inch-long ceramic protective sleeves.  The four lower measuring units were driven into the can  horizontally, through 1 cm. holes and protected with double-bore ceramic i n sulators.  Their sensors were free.  No foreign extension wire was used,  because the distance between the can and the potentiometer was less than 8 feet. The measuring units were connected with the potentiometer by means of a multiple pole switch gear, which allowed reading at every two to five minutes for a l l six junctions.  Usually 50 to 60 measurements were taken  with severe burn, and 20 to 30 with moderate burn.  The room temperature  and s o i l temperature were recorded each time and the potentiometer was adjusted accordingly. The general march of temperature during the burn i n nature and i n the experiment, i s depicted i n Figures 8 to 11. There were many sources of error which caused variations i n burning effects and required, therefore, modification of time,  (l) The moisture  content varied i n the different blocks at the time of burning, because of differences of s o i l and organic substances by sites and the individual variations i n sample blocks; (2) The irregular temperature and humidity of air at the places of storage and burning resulted i n differences i n desiccation; (3) The burner did not produce a perfectly uniform flame each day i n spite  - 24 of controlled air mixture; (4) The changes to the mineral s o i l from severe burning were not obtainable on the Moss and Salal blocks, because of the great amounts of organic matter. The above reasons forced modification of the time of burning. Adjustments were based on the measured temperatures and on the degree of destruction of organic matter. The following rates were used on the different sites (Figure 9), in terms of 'surface' temperature 1 cm. below the ground surface: Swordfern site:  severe burning moderate  1750°F for 30 minutes 1200°F " 1 5 "  Moss site:  severe burning moderate "  1850°F " 3 5 1550°F " 15  " "  Salal site:  severe burning moderate  1750°F " 3 5 1000°F » 15  " "  11  11  From the burning records the following data were compiled: maximum and average temperature on the surface during the most intensive 20 or 10 minutes of burning for the severe or moderate; average temperature for depths of 2 and 4 inches; and depth of the burned-out or destroyed layer, as a loss from the s o i l block (Table V).  The sinking of the surface, expressed as a  loss of the surface material, includes both destruction of humus by burning and compaction by shaking during transportation.  This latter mechanical  loss was estimated at about half an inch for Swordfern blocks, and threequarters of an inch for Moss site blocks.  Salal blocks had no such losses  because of their elasticity and shallowness. The different results i n four blocks within a group are apparent i n -Table VI expressed i n order of intensity.  Table VI shows also the surface  characteristics for different burning rates and intensities.  No direct  - 25 consistency i s shown between the values.  Only the destruction, expressed by  loss i n inches, indicated some relationship to the burning force.  The blocks  with insufficient moisture were those with over-burned rates, excessively deep penetration of heat, and with deeply destroyed humus layer.  As examples  of the latter, blocks 1, 6, 10 and 11 from Moss site; and blocks 1, 7, 8, 10 and 11 from Salal site should be mentioned. The percentage of sample blocks covered with noticeable remains of burning showed the following results:  Site and Burning Rate  10 to 50$  25 to 75$  mineral soil surface scorched  surface covered with ash  10 to 60$ surface covered with charcoal  Swordfern site  severe moderate  71 29  79 71  50 52  Moss site  severe moderate  50 29  64 64  79 93  Salal site  severe moderate  0 0  64 57  100 93  Severe burning produced more scorched mineral aggregates and more ash than moderate burning. Moderate burning, however, produced more charcoal than severe burning. Formation of coke was observed i n four cases on seedling blocks (Table VI), and on a Moss s o i l sample block, due to high and rapid burning, accompanied with lack of oxygen (Plates - VI, X, XII). ing slash material was involved or added.  No usual ash-produc-  This i s why only 1 to 2 m i l l i -  meters of ash were present instead of the one or more inches of ash associated with an actual slash burn.  - 26 The remarkable differences i n the productivity, consistent for a l l replicas and for each species, proved that the two burning rates applied were uniform i n their effects within their own ranges and represented two different grades of burning.  Not only did the surface temperature prove to be  directly a decisive factor, but also the rate of penetration of f i r e into the mineral layer.  The mineral s o i l to a depth of about 3 inches was affected by  high temperature (500 to 700°F) only on the bare Swordfern blocks. The condensation of water vapor reported i n the literature (Uggla 1958) was observed i n most cases by the "sweating" cables of thermo-couple wires and on glass thermometers.  The condensation of vapor was so rapid i n  the shallow Salal site blocks, that at the start of burning water drained from the bottom of the cans.  A temperature decrease was also observed quan-  t i t a t i v e l y i n a number of blocks at a depth of 4 inches.  In 24 cases from  a l l 84 ( 2 9 $ ) , the thermo-couple sensors recorded a continuous decrease i n temperature.  This drop went on for about 10 minutes, showing lower values  than at the start, up to a maximum difference of 0.150 m i l l i v o l t s , which i s equivalent to 5°F ( 2 . 7 8 ° C ) .  This procedure was measured i n 21$ of the cases  with the Swordfern site and the Salal site, and i n 43$ of the cases with the Moss site.  The best water retention capacity of the Moss site l i k e l y re-  sulted i n the development of a belt of condensation.  The intensive vaporiza-  tion of s o i l water heated from above u t i l i z e d heat from cool parts lying underneath before i t started to condense again. vaporization absorbed some heat from the s o i l .  The endothermal process of This i s why the temperature  at about 4 inches of depth seldom exceeded 100°F (38°C) i n Swordfern and 200°F (93°C) i n Moss site. however.  The shallow Salal site was often overheated,  - 27 The measured decrease of temperature caused by vaporization furnished new evidence to corroborate the findings of many authors about the thermo-dynamic role of moist humus (Hesselman 1916; Lutz and Chandler 1946; and Uggla 1958a). Sowing the Tree Seed After burning, the blocks were arranged on benches i n the greenhouse.  The excess upper rims of cans were cut except for a small rim that  prevented escape of irrigation water.  Holes from the heat gauges were closed.  Labels were put on the cans, showing the number, site, burning rate and species of each block (Figure 4).  The shorter blocks were elevated to give a  uniform surface level for a l l blocks. Fifty stratified seeds of each species were seeded on each block. Soil sample blocks preserved for chemical analysis were not seeded (Table III). The seeds were regularly spaced on the moistened s o i l surface (Figure 3 ) . can wall.  The outer rows of the seeded square were lg inches away from the Wide-headed nails were used to mark the places for the seed on  clean s o i l surface, and a pattern with 1 cm. holes was used to place seeds on the rough surface.  The seeds were gently pressed into the s o i l to pro-  vide a 5 mm. cover for Douglas-fir and a 1-2 mm. cover for the other two species.  The seeds were pushed into the rhizoid region of the moss cover.  Any vegetation which hindered the sowing was slightly trimmed.  The moisture  of the surface was maintained with moistened towel paper. The ash layer, which was never thicker than 2 mm., quickly disappeared through i n f i l t r a t i o n by water into the s o i l . there was no visible ash on the blocks.  By the end of April  - 28 Micro-Climatological Conditions and I r r i g a t i o n On A p r i l 19, I960, a Stevenson screen was i n s t a l l e d with a F r i e z hygrothermograph. Temperature and humidity data are presented i n Figures 6 and 7. Meteorological conditions from stations near the sample c o l l e c t i o n are shown i n Figure 2.  *  To avoid intense i n s o l a t i o n i n the greenhouse, the blocks were shaded with newspaper sheets i n A p r i l . greenhouse was coated with whitewash.  On A p r i l 29th the glass roof of the Routine heating and v e n t i l a t i o n con-  d i t i o n s i n the greenhouse were maintained. During the c h i l l i n g period, from November 7, I960 to February 9, 196l, s p e c i a l measures were introduced f o r heating and v e n t i l a t i o n . P o s i t i o n of cans within the four-block group of each variant was changed weekly i n A p r i l and May, to avoid differences i n s o i l temperature. To improve the uniformity of heat conditions, a peat-moss i n s u l a t i o n of metal cans was applied at the end of May, I960. The south side was marked on each can to ensure the seedlings the same compass p o s i t i o n a f t e r any change i n arrangement, and to i d e n t i f y the surface with the sketch. The addition of l i g h t i n g from August 18, I960, to September f a i l e d to prolong the growing season of a l l seedlings.  23,  This late-summer  a r t i f i c i a l l i g h t was supplied with s i x 150-watt incandescent bulbs, operating each day from 7:00 to 9:00 P.M.  On completion the blocks were  transferred to t h e i r f i n a l premises f o r the winter c h i l l i n g and accelerated spring growth (Figure 4).  to follow p a g e  5 i SALAL SITE  L J • I I  *'c" 1  "  SALAL SITE I  • • • • r* • • • • • u »• • V? n 77? • • «liB • • « •  SAMPLES  \s\\N\s\  I SWORDFERN SITE I  I  MOSS SITE  SAMPLES  SAMPLES  MOSS SITE  SWORDFERN SITE SOUTH  TH - THERMO-HYGROGRAPH  FIGURE 4 .  -  LAYOUT OF SEEDLING  BLOCKS AND SOIL BLOCKS IN T H E  GREENHOUSE. SEE CHART OF SYMBOLS.  28  to f o l l o w  130  130  230  220  (89)  (86)  250  0 (86)  230  0  130  240  220 ©  (88)  240  (70)  0  130  (92)  130  125  130  170  125  170  180  170  © 240 0 250 (102) (105) _  page  O  250 -  230  (104)  © 190 (96)  175  170  SOUTH  ®  5 0 0 - W A T T INCANDESCENT BULB  (90)  VERTrCAL DISTANCE O F THE B U L B - C M  230  INCIDENT LIGHT INTENSI TY - FOOT C A N D L E S  FIGURE  5. DISTRIBUTION OF ARTIFICIAL LIGHT FOR BREAKING DORMANCY.  - 29  Irrigation with d i s t i l l e d water had to ensure the nutritional requirements i n an equal distribution for each block, regardless of i t s plant population or different s o i l properties.  The irrigation was also, i n this  case, a substitute of vertical seepage for eluviation of ash and other nutrients after the burn.  Table VII compares the amount of water used for  irrigation to the meteorological averages for many years and to the records of the current year.  Two-litre Erlenmeyer flasks were used with a suction-  pump outlet for irrigation. precipitation inches.  The volume of flasks was adjusted i n terms of  The irrigation was performed every second evening. Seedling Population  On May 5* I960 additional planting was necessary to supplement the population on some blocks to ten, to guarantee at least five plants after thinning.  Douglas-fir did not require any replacements.  Western hemlock  needed four additional germinants for the Moss site and one for the Salal site.  Western redcedar was transplanted thus:  27 on Swordfern site; 36 on  Moss site; and 28 on Salal site.  There was no relationship, i n the need for  transplants, with the treatment.  Half of the supplied seedlings remained  until the end of the experiment. In thinning, the dying, crippled, chlorotic seedlings were selected for  removal.  Then those with damaged leaders, and f i n a l l y those with double  leaders were removed.  Subsequent thinning removed many of the replacements  because original seedlings were preferred. The 1.  number of plants on a block changed chronologically as follows:  April 9 to 17, I 9 6 0 - germination -  50 seeds and their germinants  Chilling  100  I  I  IA I  I  I 1—I—f  90 u:  if) Ui UJ  80  or o UJ 70 o •  u ) cc •D 60 UJ  50 0 Z. ul  AO  Weeks Months. Years FIGURE 6 .  B412345I123411234 12345 1234 12345  A| M 1960  1234 1234 N  12345112341123411234112345 12341  M 1961  WEEKLY T E M P E R A T U R E S IN T H E G R E E N H O U S E DURING THE  EXPERIMENT.  M  Weeks Months Years FIGURE 7. WEEKLY RELATIVE HUMIDITY IN THE GREENHOUSE DURING THE EXPERIMENT.  o o o TJ D  IQ 5)  - 30 2.  May 5 - regulation (western hemlock and western redcedar) (substituted to 10)  3.  May 14 (Douglas-fir) ) June 14 (western hemlock and western ) - thinning to redcedar) )  4. January 22, 1961 (Douglas-fir) February 11 (western hemlock and western redcedar)  ) ) )  10 germinants  thinning to  5 seedlings  3 seedlings  Breaking of Dormancy On November 7, I960, when a l l the seedlings ceased their growth and the Douglas-fir and western hemlock developed buds, the heating system in the greenhouse was turned off and windows were opened to produce a natural chilling period of 90 days.  On February 9, 1961, the greenhouse windows were  closed and the regular heating apparatus connected.  There was only one week,  that of from January 23 to 30, 196d), when the temperature dropped below 40°F, and only one day, January 28, when i t dropped to 33°F. On February 9, 1961, a r t i f i c i a l light was introduced.  Ten 500-watt  incandescent bulbs, Type GE, were used each day from 5:00 P.M. u n t i l 1:00 A.M. The distance of bulbs from the block surfaces varied to produce equal light for a l l blocks.  The light intensity on each block was checked  with a Brockway exposure-meter, Model S, Sekonic Studio. ination under the bulbs was 220 to 250 foot candles. on the edges was 125 foot candles.  The average illum-  The minimal intensity  The vertical distance of bulbs from the  block surface ranged from 70 cm. to 105 cm. (Figure 5). The a r t i f i c i a l light was concluded on May 5, after 85 days. The eight hours of a r t i f i c i a l light resulted i n the breaking of dormancy and a vigorous growth of a l l three species.  v  to follow p a g e 30  F  C  1200  o r-o  CD  100QJ  GROUND SURFACE  30  TIME - MINUTES FIGURE 8. MARCH OF TEMPERATURE  DURING A SLASH BURN,  ADAPTED FROM E. UGGLA.  to follow page 30  C  F  I90a o o  SWORDFERN SITE  SEVERE BURN  — \ MOSS SITE SEVERE BURN  SALAL SITE  1500  in  UJ u>  -  cc  UJ  a  UJ 1000 DC  5 CC  -  UJ  a. UJ  500  6Q  -o I  10  " i  15  F I G U R E 9.  MARCH THE EACH  1  1  1  20  30  35  r~  50  AO  TIMEMINUTES OF TEMPERATURE DURING LABORATORY  BLOCK SITE  SURFACE.  AVERAGES  A N D BURNING  RATE.  60  OF FORTEEN  BURNING F O R  BURNINGS  FOR  to follow page 30  F , C 1A00_ -  SEVERE BURN  o "Wo  SWORDFERN SITE  — MOSS SITE SALAL SITE,  1000 © •o in  m UI Ui  a:  O  ai UJ  SEVERE BURN  uJ  cc  2 UJ Q-  ui  SEVERE BURN  500.  V  (MODERATE BURN o |—o  7/ MODERATE BURN  '  /  —  MODERATE BURN  '  •  -  ^^v.  --'^ .,  \  \.  *" — ' ^ i :  .  /  \  V <  60, 0_ - o 10  15  20  1^  30  TIME-MINUTES  T A0  I GO  60  FIGURE 10. MARCH OF TEMPERATURE DURING LABORATORY BURNING FOR A DEPTH OF TWO INCHES. AVERAGES OF FORTEEN BURNINGS FOR EACH SITE  AND BURNING RATE.  to follow page 30  F  C SWORDFERN •  400_ o SEVERE  1  o  SITE  ' SALAL  o  & 3 0 0  ' MOSS  SITE  SITE  BURN i  •  o '  UJ  '  /  \  o  uJ DC  3  < 200  o  UJ Q.  SEVERE  BURN  SEVERE  BURN  .'/ //  uJ  o  //  100_  //'  •>»  v.  60. —~~MODERATE  1  0  G  1 10  • 1G  1 20  1 30  BURN  ' 3G  1 40  1 GO  60  TIME-MINUTES  FIGURE 11. MARCH OF TEMPERATURE DURING LABORATORY BURNING A DEPTH OF FOUR INCHES. AVERAGES OF FORTEEN INGS FOR EACH SITE AND  BURNING RATE  FOR  BURN-  - 31 Seedling Growth and Dry Matter Production A r e g i s t e r was prepared f o r each block to record c h a r a c t e r i s t i c s and changes on the block.  A f t e r reduction of seedlings to f i v e , each seedling  was  l a b e l l e d and i t s place marked on a sketch. The following t a l l i e s with subsequent analyses were c a r r i e d out during the experiment: (a) (1) (2) (3)  (2) (3)  J u l y 1, I960 Aug. 20, i960 Dec. 30, I960  (Figure  13),  Account of growth i n the f i r s t growing season - evaluation of f i r s t spring growth (Figure 15), - evaluation of the summer growth (Figure 16), - evaluation of the f i r s t - y e a r growth (Figure 17 and Table X); (c)  (1) (2) (3)  germination  A p r i l 16, I960 - t e s t of e a r l y germinants, May 5, I960 - germination t e s t a f t e r complete germination May 15, I960 - t a l l y of t h r i f t y germinants (Figure 14); (b)  (1)  Account of  Account of growth i n the second year  A p r i l 20, 1961 - evaluation of stimulated e a r l y growth (Figure 18), June 25, 1961 - evaluation of second spring growth (Figure 19), J u l y 8 and 20, 1961 - measuring and weighing the completed plant crop a f t e r the f i n a l removal (Figures 20 to 23). In Section (a), the number of germinants and t h e i r q u a l i t y were  examined.  The germination  capacity was  calculated and compared or r e l a t e d  to the burning conditions on each s i t e f o r each species. The t h i r d assessment selected a l l sound germinants and r e l a t e d t h e i r number to the standard germination  capacity.  A l l i n j u r e d or defective  germinants were removed a f t e r the count, and the type of damage was  recorded.  During thinning, the root systems of the removed seedlings were examined, and top-root r a t i o s by length were determined. The second section (b) recorded seedling growth i n the f i r s t  year.  - 32 During measurement each seedling was individually handled.  Height of the  stem, length of largest needles, and the number of branches were counted and color of foliage was expressed i n the f i r s t evaluation.  For Douglas-fir the  type of branching and for western redcedar the length of largest branch were also recorded.  Notes were made on other features such as bud form and  color. The second evaluation (Aug. 20, I960) added to the previous characteristics,  stem diameter 1 cm. over the ground to the nearest l / l O mm.,  total length of branches and stem characteristics.  The secondary and  tertiary branches on hemlock were counted. The third assessment at the end of the first-year growing season examined the previous characteristics, and the lammas growth. The third section (c) covers development i n the second year.  The  growth started with the breaking of dormancy about the middle of February, 1961, with redcedar, March 15 with hemlock, and March 25 with Douglas-fir. The f i r s t detailed measurements of a l l seedlings were taken on April 20, 1961, after the last thinning to three seedlings.  The f i r s t and second  assessments i n the second growing season (1961) measured only height growth, bud development and changes i n colour of foliage i n the two phases, winter and spring growth.  The second t a l l y on June 25, 1961, recorded final growth  of seedlings already resting and growth curves were prepared. On removal, the seedlings were washed, shaken to get r i d of excess water, and the root was removed.  Simultaneously with the snipping of roots  at the point of the root neck, the diameter and the length of shoot and root were measured i n millimetres. of a gram.  Root weight was taken to the nearest hundredth  The root and top parts were sealed in paper bags with wire staples for room temperature drying for about ten days.  The plants were oven dried  in the paper bags for 24 hours at 80°C (180°F).  The dried plant parts were  weighed again separately on a Mettler Optical Balance, Model K-7, to the nearest hundredth of a gram.  Root and top, and total dry weight of the plant  was computed. For calculation i t was decided to group together the absolute measurements and averages for a given characteristic, e.g., height or weight for a l l the seedlings from a single block, since these plants of the same species and common origin received the same treatment on the same s o i l block i n uniform micro-climatic conditions. measurements or block sums for weights.  This provided block averages for For any treatment, then, affecting  one species, one site and one burning rate, four such block averages or sums are available, because there are four replicates of each species, site, and treatment combination i n the experiment, resulting in 108 such block units. Accompanied Vegetation on Blocks The original vegetation was preserved on a l l blocks and described. The mosses, ferns, herbaceous plants and woody plants were identified by V. J . Krajina; fungi by R. J . Bandoni (Appendix III). On May 20 and July 15, I960, further descriptions reported the remaining vegetation. A third description of vascular plants was carried out i n December. This vegetation did not change u n t i l the end of the experiment.  Fungal  vegetation was counted i n addition to the above on November 25, I960 and February 10, 1961.  - 34  Seedlings from Field To obtain information on seedling development i n nature, wild seedlings of the three species were collected from the places of sample block collections.  Thrifty seedlings coming from germination i n the spring of I960  were excavated, and used for measurements (Tables XIII and XIV).  A number of  seedlings from the f i e l d were also preserved for herbarium records (Plate XVII). Soil Chemical Analyses To relate the findings of plant growth and dry matter production to the changes i n the s o i l nutrient balance, a series of s o i l analyses was undertaken. The plan was to analyze s o i l blocks without seedlings, in order to follow chemical changes due to f i r e alone.  Two sample blocks from each  variant were preserved for this purpose (Table III), and were treated equally to the other seedling blocks. In June, I960, when the incorporation of ash was completed and when the growth of seedlings started, one-third of each s o i l sample block was cut off vertically. sectioned blocks.  Tables XVII - B, C, present descriptions of layers of the The remaining two-thirds of each block was closed again,  with the replaced metal wall. sections.  Plates XIII to XVI show such s o i l cross-  When the experiment was concluded i n June, 1961, samples from the  same layers were taken again. Soil pH values were measured from the surface layer and from the central part of a l l seedling blocks of average production (Table XVIII - C). After air-drying, the s o i l samples were sifted by Tyler Standard  - 35  Screen, Scale No. 10 (9 meshes - 1.98 mm.) to select coarse particles.  The  following chemical properties were examined by standard methods (Appendix IV), for each sample i n two replicates:  s o i l pH, cation exchange capacity, per  cent organic matter, per cent nitrogen, miliequivalents for 100 grams for calcium, potassium and magnesium cations, and p.p.m. for phosphorus.  Per  cent saturation for the named cations was computed, and organic matter per nitrogen expressed. More than 120 samples were analyzed from 60 s o i l samples.  Parallel  results from the same layers, taken i n the following years, were compared and related to the corresponding item from the f i e l d collection.  A l l the a v a i l -  able information from analyses was grouped by burning rates and related to the values of plant production. Note on Physical Soil Properties The character of the experiment did not make possible proper s o i l physical observations.  Only some obvious marks and phenomena were available  to compare present conditions to those generally accepted i n the literature. The usually observed postfire results of heat and burning were present on the sample blocks and described quantitatively.  The formation of  ash, charcoal and aggregates of the mineral s o i l particles was recorded along with coke production i n a few cases. The consistent watering eliminated the disadvantage of a possible increase of percolation rate and decrease of water-holding capacity of the s o i l after burning.  The improved aeration l i k e l y promoted decomposition,  resulting i n a beneficial increase of nitrogen transformation.  Photographs and Seedling Collections The lay-out and the march of the experiment were recorded by a number of photographs, mostly coloured. At the end of seedling growth i n A p r i l , 1961, a series of black and white photographs was taken.  A more complete series i n color was taken on  June 30, on completion of the experiment, when a l l the possible combinations were recorded.  Color changes on foliage were also recorded.  From the large  number of photographs, some are presented on the Plates (Appendix V). During the experiment, the thinned seedlings, along with those c o l lected on experimental plots i n the forest, were preserved i n a herbarium. Some herbarium sheets are presented on Plate XVII. Statistical Analysis The effects of two burning rates and of unburned control variants were compared to each other for sites and species.  Analysis of variance  and t-tests were used for each site and species for the two series of final measurements.  In the f i r s t series heights of individual seedlings served  as the basic data, and i n the second, dry weight of the total crop on each block was considered.  Height data were analysed because i t allowed con-  sideration of individual variation, but i t was impossible to obtain weight data for individual seedlings because of the interwoven and broken root systems (especially with redcedar). An example of the steps i n the analyses i s given i n Appendix II for each series (height and weight).  Table XXXII gives the levels of sig-  nificance between treatments for each species on each site when height and weight comparisons are made.  CHAPTER THREE - RESULTS AND DISCUSSION Changes i n Composition of the Accompanied Vegetation The original plant cover on s o i l blocks was described after collection (Appendix III) and i t remained relatively unchanged during the f i r s t winter in the greenhouse (Plate - II). Burning i n March, I960, destroyed the vegetation on burned blocks and the plant cover on unburned blocks was sheared to facilitate Appendix III presents the species for each site. only on some blocks are marked with the number of the block.  sowing.  Species occurring The description  shows that the original vegetation on May 20 was well preserved on unburned blocks, except that mosses died during the f i r s t winter. Eurhynchium oreganum, Rhytidiadelphus loreus, Hylocomium splendens and Plagiothecium undulatum were gradually surpassed by Funaria hygrometrica.  Some temporary  regeneration of Plagiothecium undulatum was noticeable. The plant cover on burned blocks was composed mainly of newcomers (mosses, liverworts, ferns and angiosperms). roots or rootstocks survived the burning.  Only a few species with deep  The severely burned blocks had no  survivorsj the moderately burned blocks i n many cases supported root suckers of Rubus species and Gaultheria shallon on both Swordfern and Salal blocks. The Moss site did not produce root suckers and i t s shallow-rooted, shrubby plants did not survive burning.  In one case, Pteridium aquilinum sprouted  on a severely burned Swordfern block from deep roots - an indication that i t may survive even severe burning. A great number of fungi soon occupied nearly a l l burned block surfaces, except the severely burned Swordfern site and a few blocks of the Salal site, which had a very strong charcoal cover.  No fungi occurred on  - 38 unburned blocks. When a l l ash material disappeared from the block surface i n May, I960, new plants appeared.  In the f i r s t half of May a slimy cover of uniden-  t i f i e d algae was noticeable on many blocks.  Only 7 per cent of Swordfern and  Moss blocks had algae, but 59 per cent of the Salal blocks.  The predominance  of undecomposed organic material l i k e l y supported algae on Salal blocks.  No  relationship to the treatment was noticed. The vegetation was trimmed again on July 15, I960.  Before this  reduction and shearing, a third survey of vegetation was carried out (Appendix II - 3). Plants listed i n the previous enumeration were not repeated.  (See also the Plates.). The second after-burn description on July 15 showed the following  plants established on the burned s o i l surface; Senecio sp., Populus trichocarpa, Salix scouleriana, Alnus rubra, Funaria hygrometrica and Leptobryum pyriforme.  On some blocks Polytrichum .juniperinum, or on others Marchantia  polymorpha, were present. The difference, i n the composition of vascular plants, between the burned and the unburned blocks was maintained as before. only on burned blocks.  Fungi appeared  The greenhouse mosses gradually invaded the surface  of a l l blocks. After the July plant identification there was no noticeable change in plant cover.  The vegetation on blocks was l e f t undisturbed; only intru-  sive species, such as Oxalis, Hypochaeris, Begonia and some exotic ferns were removed.  The growth of accompanied plants was controlled only where i t  interfered with development of the tree seedlings. The changes i n moss cover were recorded f i r s t on August 18, I960.  - 39 The burned and the unburned blocks of the Swordfern site were already covered by 65 to 85 per cent of the surface area, and the burned Moss site and Salal site blocks by 45 to 80 per cent.  The unburned blocks of the Moss site were  covered by a complete mat of old dead moss, and the Salal site was 35 per cent covered with dead moss and 65 per cent with new mosses. The post-fire light-demanding mosses such as Funaria hygrometrica, Leptobryum pyriforme. Polytrichum .juniperinum, and liverwort Marc nan t i a polymorpha gradually dominated a l l blocks. The. evaluation of the autumn fungus flora i s presented i n Appendix III - 4. Fungi of the genus Boletus were present on ten severely burned blocks, and on two moderately burned blocks (14 per cent). On December 5, whitish and yellowish 5-6 cm. colonies of two unident i f i e d Eumycetes developed on nine burned blocks (11 per cent).  For the f i r s t  time, four unburned blocks i n the Moss site (28 per cent) and four i n the Salal site (28 per cent) supported the same fungus vegetation (Appendix III -  5). At the conclusion of the growing season, the plant cover of the blocks was compared to the July condition (Appendix III - 6).  The previous  striking differences between the unburned and burned blocks and between sites already disappeared.  The invaders occupied a l l the space between seedlings.  Fungus flora prevailed on the following proportion of a l l burned blocks: Swordfern 81 per cent, Moss 79 per cent, Salal 57 per cent.  Unburned blocks  had fungi on 71, 29 and 42 per cent of the blocks, respectively. During the rapid growth of seedlings i n the 1961 prevernal period, most associated vegetation was suppressed or removed with the f i n a l thinning of seedlings, and the plant cover had l i t t l e further indicator value.  - 40  In early February, 1961, probably due to the effect of hastened spring growth, a new fungal flora was apparent, mostly on severely burned blocks and less on moderately burned and unburned surfaces.  Many of the  Swordfern site blocks were infested, but very few of the other two sites. The distribution i s shown i n Appendix III - 7. blocks supported fungi:  The following percentage of  Swordfern 78 per cent, Moss 45 per cent, and Salal  14 per cent of the burned blocks; while Swordfern 14 per cent, Moss 0 per cent, and Salal 14 per cent of the unburned blocks. Contrary to general opinion (Johnson, 1946; Tarrant, 1956b, 1957; and Pac. N. W. Exp. S t . , 1957), i n this experiment fungal vegetation prevailed on burned blocks.  The unburned control blocks were slightly occupied  by fungi i n the second year.  The consistent charcoal surface and the severe-  l y burned Swordfern site were free from fungi at the beginning. I960, many burned blocks were invaded by fungi.  In July,  The Ahlgrens (i960) quoted  four authors who reported stimulation of some Discomycetae and Agaricaceae. The f i r s t fungi (Eumycetes) appeared on unburned Moss and Salal blocks i n December, I960, and formed at that time greater infestation than on burned blocks. The number of species was remarkable as was the number of specimens on each block.  Twenty species were identified and the number of speci-  mens varied from two to twenty on each block.  At the f i r s t Craterellus,  Coprinus, Spicaria, Lamprospora, Patella albospadica and Myxomycetes were present on many of the burned blocks.  Peziza, Agaricus, Boletus, Telephora  and Craterellus species were characteristic from July, I960. At last i n February, 1961, Polypoms, Craterellus, Stereuro, and Galera species appeared mostly on burned, and scarcely on unburned blocks.  - 41  No decrease i n mycorrhizal l i f e was noticed on burned blocks, as stated by some authors (Pac. N. ¥ . Exp. S t . , 1957). On the contrary, abundant mycorrhizae were found on a l l good seedlings i n the second year. No similar observations were made i n the f i r s t year. Establishment of Seedlings, May 5, I960 Seeds which had been stratified for 93 days were sown 50 to each block; on April 9, Douglas-fir and western hemlock, and on April 10, western redcedar.  The germination started on April 13 with Douglas-fir, April 15 with  western hemlock and April 17 with western redcedar. To produce comparative data for the evaluation of germinative capacity, simultaneous standard germination tests were carried out with 50 seeds from each species i n the greenhouse (Figure 1 2 ) . In this test Douglasf i r produced i n six days 78 per cent germinative capacity, western hemlock i n eleven days 68 per cent, and western redcedar i n three days a 28 per cent germinative capacity.  The above values were considered as standard germina-  tive capacities for each species.  The actual values reached on s o i l blocks  were counted as percentages of these basic values. When the germination was concluded by April 23, a count of a l l germinants was carried out.  The second account on May 5 recorded the final re-  sults, shown i n Table VIII and i n Figure 13. Douglas-fir seeds nearly approached the standard results of germination, with the exception of the unburned Salal site blocks (49 per cent); western hemlock showed f a i r l y good results on Swordfern and Salal sites, but failed on Moss site (55 per cent); and western redcedar had the lowest germination (30 to 39 per cent).  to f o l l o w  60  page  DOUGLAS -FIR  A. IN VERMICULITE 6CL  A0l 20~ Q2  60~ AO]  WESTERN HEMLOCK  2oL l±J  a UJ  a.  3 80_  'WESTERN REDCEDAR  DOUGLAS -FfR  B.IN ASH 60L  AOl 20l 0 1960 A PR 8 9 10 li 12 13 1A 15 1617 18 19 20 21 22 232A 25 FIGURE 12. STANDARD PETRI DISH GERMINATION TESTS .  Al  Burned blocks gave a better germination than unburned ones. Thirty-seven per cent of the Swordfern site burned blocks had higher values than the standard 78 per cent germinative capacity of Douglas-fir.  On the  Moss site 25 per cent, and on the Salal site 12.per cent had better results than the standard.  With western hemlock, one severely burned block from the  Salal site, and one from the Moss site had better results i n germination than the standard tests. Pickering (1910) investigated the effect of heat at 392°F (200°C) which inhibited seed germination through a production of non-acid, nitrogenous materials.  Wilson (1914) found a delayed germination i n s o i l  affected by a heat of 347°F (175°C).  No such effects were observed i n this  experiment. In the final average, burned blocks had better germination results than the unburned ones (Figure 13). The physical character of the surface influenced the germination to some degree.  The dense moss surface of the unburned Moss site blocks re-  duced the results noticeably with hemlock and redcedar.  The homogeneous  surface of the Swordfern blocks proved to be the most successful medium for germination. The presence of ash and charcoal did not show a uniform effect on germination.  Ash slightly promoted germination of Douglas-fir on the Sword-  fern and Moss site blocks, and did the same with hemlock on the Swordfern site blocks.  On the contrary, ash hindered germination of redcedar on the  Swordfern and Moss site blocks.  These results are consistent with those  shown in petri dishes (Figure 12), where ash strongly reduced the germination capacity of western redcedar.  The Salal site gave no correlative  SWORDFERN SITE S M U  150  MOSS SITE S M U  SALAL SITE S M U  DOUGLAS-FIR 100 J o < z WESTERN HEMLOCK  cc  50  J  0  _J  Jl  -TLn  o 100  -OJT  UJ  o  cc  50 J  o  Uf  WESTERN REDCEDAR  t—  CO  3  S.i o o 50 1  Li-n  0_J  flJlN  TJ4  Jul  FIGURE 13. RELATIVE GERMINATION ON SEEDLING BLOCKS, MAY 5,19 60. GERMINATION CAPACITIES ARE ADJUSTED TO STANDARD VALUES FOR EACH SPECIES: D - 78, H - 68, C - 28 •/. • SEE CHART OF SYMBOLS.  - 43 results and had great range of variations.  Charcoal showed some positive  effect on germination. Many authors observed the effect of ash on seed germination. (1950) found reduced germination on concentrated ash.  Baker  Gayle and Gilgan (1951)  stated that Douglas-fir seed had high germination capacity on leached surface. Muri (1955) found that ash slightly affected germination.  This experiment  also supports the fact that, although concentrated ash affects germination, leached surface has l i t t l e effect.  The concentrated ash increased germina-  tion with Douglas-fir by 2.6 per cent, but reduced i t with hemlock by 48.6, and with redcedar by 82.2 per cent. Only 8.2 per cent of a l l 1236 Douglas-fir germinants was found unthrifty.  The unburned Swordfern and Moss blocks had the smallest number of  such dying and curved germinants (2.1 and 0 per cent), and Salal blocks had the highest percentage of such defects (10.8 per cent).  Damping-off occurred  with nine Douglas-fir germinants, less than one per cent. mostly on burned blocks. noticeable defects.  These occurred  Western hemlock and redcedar germinants had no  No effect of stratification was apparent.  The percentage of defective two-week-old Douglas-fir seedlings on May 5, I960 was as follows: Severely bumed blocks  Moderately burned blocks  Unburned control blocks  Average  Swordfern site Moss site Salal site  9.4 8.7 4.6  13.3 9.3 14.1  2.1 0 16.9  8.4 6.0 10.8  Average  7.6  12.2  4.4  8.2  The number of cotyledons was counted and those with more than a  - 44 normal number of leaflets were recorded.  Fourteen evenly distributed Douglas-  f i r germinants from 1236 ( l . l per cent) had eight cotyledons instead of five or seven.  Thirty-four hemlocks had four cotyledons instead of three, which  represented 4 per cent of a l l the 846 germinants. germinants had more than the normal two cotyledons.  None of the 176 redcedar There was no correlation  between the number of cotyledons and the treatment. Franklin (1961) found the following number of cotyledons:  Douglas-  f i r , 5 to 8 and rarely 9 or 10; western hemlock, 3 and rarely 2 to 4; western redcedar, 2 and seldom 3. Hypocotyl and root length, i n millimeters, on May 5> I960, was as follows: Hypocotyl average Douglas-fir western hemlock western redcedar  32 12 12  range 25 - 38 6-18 6-18  Root average 43 18 12  range 32 - 75 6-30 6-18  Franklin (1961) found the following data for the hypocotyls: Douglas-fir, 15 to 35 mm.; western hemlock, 6 to 15 mm.; and western redcedar, 6 to 16 mm. Only about 5 to 10 per cent of Douglas-fir germinants had dormant plumules or were coated i n the seed shell, by May 5. More than a half of western hemlock germinants, however, had a resting plumule at that time. None was apparent with redcedar. On both Swordfern and Moss sites the one-month-old Douglas-fir seedlings penetrated deeper i n unburned control blocks than on burned blocks. Hemlock and redcedar had deeper root penetration i n burned blocks than i n the  - 45 unburned variants.  The distribution of nitrogen supply may have been respon-  sible for this variation. Survival of Seedlings, May 15, I960 The second check of four-week-old germinants was performed on May  15, I960 (Figure 14)• The actual numbers of thrifty plants were related, i n per cent, to the standard germinative capacity of the species.  The following  example shows the method of calculation: Swordfern site—block no. 11 had 42 sound germinants from 50 seeds. This number represents 84 per cent actual survival, and 108 per cent adjusted by the 78 per cent standard germinative capacity of Douglas-fir seeds.  This  method allowed a common basis to compare the three species, with different germinative potential. There are yet no strict relationships i n the results.  The severely  burned surface resulted i n somewhat more thrifty germinants only with Douglasf i r on the Swordfern and Salal site blocks.  Hemlock showed the best results  on the unburned Swordfern blocks and on the severely burned Salal blocks. Redcedar had the worst results on Salal blocks, particularly on the severely burned group. In general, the sequence of growth i s as follows i n decreasing order: For the sites:  Swordfern, Moss, Salal, with Douglas-fir and redcedar; Salal, Swordfern, Moss, with hemlock;  For the burning rate: For the species:  severe, moderate, unburned;  Douglas-fir, hemlock, redcedar.  Twenty per cent of the 1236 Douglas-fir germinants were defective; 29 per cent of the 854 hemlock; and 25 per cent of the 176 redcedar.  These  150  SWORDFERN SITE S M U  MOSS SITE S M U  SALAL SITE S M U  —  DOUGLAS - FIR \ 100 -  ITU  ' J • 50<  1  o  3  —  WESTERN HEMLOCK  -  STOO <->,\ cc  £ 50 j Q -  , fin  A  *  i,o  £  —  i  Q  -5 too -  iln  -50 0  -  b l  a o  FIGURE U.  SURVIVAL OF FOUR-WEEK - OLD  GERMINANTS , MAY 15.1960. ADJUSTED VALUES  TO STANDARD GERMINATION CAPACITIES. SEE CHART  D  OF SYMBOLS. cn  defective seedlings were equally distributed on blocks, regardless of site or burning rate.  Douglas-fir proved to be the hardiest and hemlock the most  sensitive for i n i t i a l survival.  Hemlock had the most irregular development.  A l l the blocks were thinned to ten germinants, including those added on redcedar and some on hemlock blocks.  A l l uninjured removed seed-  lings were preserved for the herbarium. The height and root length of removed seedlings was measured. Douglas-fir, after one month, had active growing tips, with from zero to seven lateral buds.  The length of shoot (S) and root (R) averaged  i n millimetres was as follows: Severely burned blocks  Moderately burned blocks  Unburned control blocks R  Site  30 25 30  I II III  40 35 45  25 25 30  35 35 35  25 35 30  45 50 40  The root length (equal to root penetration) i n Douglas-fir was noticeably larger on the unburned Swordfern and Moss blocks than on burned blocks.  Seedlings on the burned Salal site were t a l l e r than on the burned  Swordfern and Moss sites.  These evidences refer to a nutritional increase  i n the upper layers of s o i l . The remaining seedlings of western hemlock had active leader tips, and carried up to seven lateral buds. i n millimetres was as follows:  The length of shoot and root averaged  - 47 Severely burned blocks Site I II III  S  R  25 30 25 25 30 25  Unburned control blocks  Moderately burned blocks S  R  R  25 35 25 30 30 40  25 25 30  25 30 40  Seedlings on the Salal site were generally t a l l e r and penetrated deeper. Western redcedar had a f a i r l y uniform development. coat was shed by three weeks and a l l tips were active.  A l l the seed  Its measurements  in millimetres are presented as follows: Severely burned blocks Site I II III  Moderately burned blocks R  •R  25 20 25  50 45 22  Unburned control blocks  32 20 23  40 50 35  R  25 23 24  43 40 38  The smaller size of seedlings on the Moss site and the somewhat deeper penetration of roots on burned Swordfern and Moss blocks are noticeable.  The leading position of the severely burned Swordfern blocks i s a l -  ready evident. First Spring Growth, July 1, I960 Douglas-fir was reduced to five seedlings per block on May 15; western hemlock and redcedar were reduced f i r s t to ten per block on May 27, then to five per block on June 14. The f i r s t account of growth on July 1, I960 examined five seedlings on each block and twenty seedlings for each  - 4a group of four blocks.  (Plates VIII to XII).  The height (H), needle length (N), number of branches (B^), per cent of seedlings with long branch (B^) were counted; and the stage of bud formation and changes i n colour of foliage were checked.  For redcedar i n -  stead of length of needles, diameter of the foliage cylinder (C) was measured. Per cent of seedlings with long branches on hemlock was not counted because of their uniform quality (Figure 15). Results on the Swordfern and Moss sites for Douglas-fir and western hemlock already forecast the consistent relationship between the site and burning rate.  Severely burned blocks on the former had averages two to three  times as large for Douglas-fir and hemlock as the unburned control blocks. On the contrary, unburned blocks of the Moss site averaged much higher result than the severely burned blocks with Douglas-fir.  Western redcedar general-  l y , and hemlock on the Moss and Salal blocks, had not yet distinct trends of variations.  The most uniform values within a variant appeared with redcedar.  The t a l l plants had long needles, large stem diameter, and more numerous and longer branches; the smaller plants had small values of a l l other characteristics. The following discolorations and growth irregularities were observed: Douglas-fir: Swordfern site, on severely burned block - 11, the large seedling 5 had dotted needles and curved stem; block - 13, seedlings 4 and 5 had spirally deformed stems; on unburned block - 33, a l l five seedlings had a yellowish pale coloration.  SWORDFERN SITE S M U  MOSS SITE S M U  SALAL SITE S M U  DOUGLAS-FIR 10  5 WESTERN HEMLOCK  S o  o _:  ,10  2  UJ  x  WESTERN REDCEDAR  Jl  j J  5  J  2J  0 _ J  A  10-  J  5 0  FIGURE 15.  HEIGHT OF TEN-WEEK-OLD SEEDLINGS, JULY 1,1960. AVERAGE OF FIVE PLANTS ON EACH BLOCK  AND  OF  TWENTY FOR EACH GROUP. SEE CHART OF SYMBOLS.  - 49 Moss site, on unburned block - 42, seedling 5 had dotted needles. Salal site, on severely burned block - 3, seedlings 2, 3, 5 were yellowish pale coloured; on moderately burned block - 27, a l l five large seedlings had curved stem; on unburned block - 37, seedling 4 had red cotyledons. The above l i s t shows a nutritional irregularity on ten seedlings from a total of 120 (8 per cent), six of which were on unburned Swordfern and Moss blocks.  A l l six curved stems occurred with the over-nourished  tallest seedlings on burned blocks.  Seven mal-nourished small seedlings  were grown on unburned blocks, the four smallest of them on Swordfern site blocks. western hemlock: Swordfern site, unburned blocks - 41, 38, 35 and 30, each had two pale seedlings; 40 per cent of a l l (8 from 20); Moss site, unburned block - 20 had a l l five seedlings pale; 25 per cent of a l l ; Salal site, unburned block - 41 had seedlings 2, 3 and 4 with pale foliage (3 from 20); 15 per cent of a l l . Pale colour appeared only on unburned blocks regardless of the size of seedlings, and averaged 27 per cent of a l l hemlock seedlings. of deficiency culminated again with Swordfern s i t e .  The symptom  Hemlock was much more  sensitive to discoloration than Douglas-fir. western redcedar: Swordfern site, on severely burned blocks, 10 seedlings had purplish colour (50 per cent); on moderately burned blocks, 8 seedlings (40 per cent); on unburned blocks, no seedling changed colour.  Forty-five per cent of a l l redcedar seedlings on the burned Swordfern blocks had changed to a purple colour, while none of those on unburned blocks changed. Moss site, on severely burned blocks, 15 seedlings had purplish colour (75 per cent of a l l ) ; on moderately burned blocks, 10 from 20 (50 per cent); on unburned blocks, seven seedlings had changed colour (28 per cent). The burned Moss site blocks had 62.5 per cent of redcedar seedlings with purplish colour, and the unburned block of the same site had only 15 per cent. Salal site, on burned blocks, no change was observed. on unburned block - 34, seedlings 2, 4, 5 had purple colour and red tips (15 per cent). Redcedar had l i t t l e discoloration on unburned blocks except the Salal site.  Its discoloration on burned Swordfern and Moss was remarkable.  The distribution of discolored seedlings computed for species and site i n per cent was as follows: (a)  (b)  by species: burned blocks  3  by site:  unburned blocks  D H C  16  !Z  Average  13  18  12 27  I II III  burned blocks  unburned blocks  16 21  22 22 12  2*1 13  18  Isaac and Hopkins (1937) found a luxuriant growth of shallowrooted Douglas-fir seedlings on burned areas i n the f i r s t year after burning.  - 51 The  same seedlings turned chlorotic i n the second year.  It was the opposite  in this experiment with discoloration. A l l three sites averaged a higher number of discolored seedlings on unburned blocks than on the burned ones.  The smallest average number of such  seedlings appeared on the burned Salal blocks (2.5 per cent). Most seedlings were actively growing as far as the activity of leader tips i s concerned.  A few weak Douglas-fir seedlings, however, ceased  their growth i n the middle of June, and formed a 2 mm. brown-scaled bud for a two-month rest period.  The following resting seedlings were found on un-  burned Swordfern and Salal blocks: Swordfern: Block 37, seedlings 4, 5 40, a l l five seedlings 33, a l l five seedlings total 12  Salal: Block 36, seedling 1 total 1  On the Swordfern unburned group, 60 per cent of the seedlings were dormant by the end of June, I960; on the Salal unburned group, 5 per cent; and none on the Moss s i t e . Root development was examined on June 14 when hemlock and redcedar seedlings were removed for thinning.  There was no such possibility for  Douglas-fir after May 15, when the thinning to five was performed, because of large root systems which could not be removed without damage to other seedlings. In the following l i s t the top measurements are presented i n m i l l i metres for shoots (S) and roots (R) of the removed, uninjured two-month-old seedlings, on June 14, I960:  - 52 western hemlock: Severely burned blocks Site  Moderately burned blocks S  R  I II III  Unburned control blocks  R  S  R  45 32 32  35 30 40  40 40 35 35 45 40  35 35 40  25 35 45  22 28 40  50 45 40  35 40 30 50 30 38  30 42 28 40  25  45  western redcedar: I II III  Hemlock showed the most shallow penetration i n Swordfern and i n Moss blocks.  Redcedar had generally deeper roots.  There i s l i t t l e or no  difference with different burning rates. Redcedar seedlings developed juvenile needles on the main axis i n the f i r s t year, but the lateral branches develop, instead of needles, normal scale leaves i n the f i r s t year.  The injured seedlings, however, develop  again branches with juvenile needles from their dormant lateral buds. second year leader i s generally scaly.  The  Weak seedlings continue their  juvenile type of leader growth, even during the second year of l i f e , when their lateral branches are already scaly.  On some thrifty seedlings, few  juvenile needle shoots also burst from dormant buds on the lowest part of the stem i n the f i r s t year.  These branches, however, do not continue i n  development any more. Summer Growth, August 20, I960 By the f i r s t half of August most seedlings ceased their spring growth and developed terminal buds for a resting period.  Only a few weak  - 53  Douglas-fir seedlings started their rest one month sooner.  Redcedar had  ceased i t s growth but by the end of August commenced a more rapid, late summer growth; Douglas-fir slowed down i t s growth during the second phase; hemlock was the most continuous i n i t s growth at any time. On August 20, the following data were recorded:  height of the seed-  ling above the ground (H); length of developed needles (N), with exception Of redcedar, number of primary branches (B^); length of the largest branch (Bg), stem diameter (D).  Total length of a l l primary branches was also measured  for Douglas-fir i n millimetres.  Number of secondary and tertiary branches  were counted on hemlock seedlings.  Bud development, colour of foliage, and  stem form were recorded for a l l three species.  Damage of the seedlings and  the spreading of invaded moss cover were assessed. Douglas-fir and hemlock, on the Swordfern site severely burned blocks, had three to four times as high values, i n the length of seedlings, as the unburned control blocks.  Moderately burned blocks were intermediate,  but closer to the severely burned blocks.  Similarly, Douglas-fir and red-  cedar on the Moss site blocks reached their definite sequence, showing 30 per cent higher values i n height on unburned blocks than on severely burned ones.  Moderately burned blocks were again intermediate, but closer to the  control blocks.  On the Salal site a l l three species were superior on  moderately burned blocks.  Redcedar on the Swordfern site had similar re-  sults on the burned groups, both of which exceeded the unburned blocks i n height growth.  Hemlock seedlings on the Moss site blocks had the most un-  certain results, where the poorest growth was on unburned blocks and the best on moderately burned. height growth.  Figure 16 gives a graphical comparison for  FIGURE 16. HEIGHT OF FOUR - MONTH - OLD SEEDLINGS. AUG. 20,1960. AVERAGES AS BEFORE. SEE CHART  OF SYMBOLS.  The compilation of the total length (TL) of a l l primary branches (B), including main stem (H), of Douglas-fir seedlings, resulted i n the following numerical relationship.  The total length is equal to ten times the length of  the largest branch (B,,) with i 20 per cent error.  TL = H + 2B = 10 x Bg - 20%.  Terminal buds occurred by mid-August with Douglas-fir, mostly on the Salal site and on the unburned Swordfern s i t e .  Apparently the smallest  and the tallest seedlings entered the resting stage sooner.  The groups  averaged the following percentages of developed dormant buds with Douglas-fir seedlings, by August 20, I960.  Swordfern site Moss site Salal site  Severely burned blocks  Moderately burned blocks  Unburned control blocks  35 70 20  50 5  22  80 5 70  48  £2  Average  In.western hemlock, 30 per cent of the seedlings developed buds on the unburned Swordfern blocks and 15 per cent on the unburned Salal blocks, which of both had the smallest seedlings.  There was no definite sign of a  resting stage i n redcedar but there was a noticeable slowing of growth. The pale colour of Douglas-fir foliage, suggesting nutritional deficiency, was present i n 45 per cent of the unburned blocks of the Swordfern site and i n 10 per cent of the unburned and moderately burned Salal site. The smallest seedlings were mostly affected by this deficiency. Hemlock seedlings did not change i n colour after July 1, but redcedar showed the largest percentage of discolored seedlings, as follows:  - 55 Severelyburned blocks  Moderately burned blocks  Unburned control blocks  20  Swordfern site Moss site Salal site  10 45  14  10 5 22  Average  23.  ii  The above distribution shows a definite trend to increased discoloration with burning, and mildest effects on the Swordfern, and strongest on the Moss site.  This trend corresponds already to the definite lowest  rating of severely burned Moss site blocks. Crooked stems occurred with Douglas-fir mostly on the Salal site with the largest seedlings, e.g. block 27, with a l l five seedlings.  The  least number of crooked seedlings were on the Swordfern site. The following l i s t shows the percentage of seedlings with tertiary (3), secondary (2) or only primary (l) branches: Severely burned blocks  Moderately burned blocks  Unburned control blocks  Branching level  1 Swordfern site Moss site Salal site Average  —  —  —  2  3  1  2  3  1  2  3  55 65 60  45 35 40  -  90 75 20  10 25 80  90 15 22  10 50  SO  0 35 20  60  42  60  40  40  42  20  —  -  In the above chart the best growing group shows the highest number of seedlings with tertiary branches, and the weakest group contains the highest number of seedlings only with primary branches.  The moderately burned  Salal group with 80 per cent of tertiary-branched seedlings predicts a~ best final result for moderately burned blocks.  The 90 per cent of seedlings  with only primary branches on the unburned Swordfern blocks predicts the lowest average for these blocks i n the f i n a l account of productivity. The absence of seedlings with only primary branches on burned Swordfern blocks shows their superior trend. The Mosssite had s t i l l reverse values to the final sequence by treatment. Autumn Growth, December 30, I960 A l l seedlings of the three species had a second growth during the late summer and early autumn of the f i r s t year.  This summer growth, which  corresponds to the Lammas growth i n nature, generally ceased by the end of September.  Some Douglas-fir seedlings, however, did not conclude their  growth u n t i l December due to the a r t i f i c i a l light applied from August 18 to September 23. The following data were recorded on December 30, I960:  height (H);  number of primary branches (B)j stem diameter (D)j and percentage of seedlings with Lammas growth on leaders (L). Table IX and Figure 17.  These items are discussed i n  Bud characteristics and their degree of development,  colour of foliage, and apical dominance were also recorded. The results on height, branch number and stem diameter are slightl y changed from the previous survey.  On the Swordfern site redcedar was  best on severely burned blocks, next on moderately burned and poorest on the control blocks.  On the Moss site blocks the sequence remained unchanged.  Salal site blocks made changes with Douglas-fir and redcedar to form their final sequence i n productivity with the best results on moderately burned and the worst on severely burned blocks.  - 57 Lammas growth occurred most often on Douglas-fir on the unburned blocks.  Hemlock had most Lammas growth on the unburned Swordfern and Salal  blocks.  Redcedar showed the most Lammas growth on the Swordfern site and on  the Salal site with severe burning, and on the unburned and moderately burned Moss s i t e . Generally Douglas-fir produced Lammas growth on 31 per cent, hemlock on 5 per cent, and redcedar on 23 per cent of seedlings. produced Lammas growth i n connection with better growth. a slight positive correlation to the unburned conditions.  Only redcedar  Douglas-fir showed Hemlock had l i t t l e  Lammas growth and i t was evenly distributed on seedlings of various treatments. Some leaders on Douglas-fir were surpassed by over-growth of laterals.  The following percentages of Douglas-fir seedlings were recorded  without apical dominance.  Swordfern site Moss site Salal site  Severely burned blocks  Moderately burned blocks  Unburned control blocks  20 10 -  10 10 -  15 15 5  On the Swordfern and Moss sites, the treatments which resulted in the tallest growth produced more seedlings with dominant laterals.  The  Salal site had only one seedling without apical dominance, and i t was one with exceptionally large growth (seedling 2 on block 39J i t s height was 145 mm., more than twice as much as the average of the group, 65 mm.). Hemlock and redcedar seedlings did not lose apical dominance. In recording of foliage coloration, three grades were chosen; dark (d), normal (n), and pale (p). ' Percentages of seedlings for each item  - 58 are shown i n the following l i s t : Severely burned blocks n Douglas-fir: I . Site II. " III. 11  western hemlock: I . Site II. » III. " western redcedar: I . Site II. " III. "  Moderately burned blocks d  n  Unburned control blocks  p  i  n  15 60 70 25  100 50 50 65 35 -  100 45 55 42 42  - 100 50 50 - - 100  30 70 -  35 65 100 40 55  - 100 - 100 - 25 75  - 100 - 100 25 50 25  85 40 5  -  -  60  40  75 25  t  16  - 70 30 - 100 - 100 -  Douglas-fir produced no pale seedlings i n any treatment of the Swordfern and Moss sites, nor on the moderately burned Salal site.  Generally  small seedlings had pale colour, except that few of the smallest seedlings on the unburned Swordfern site were dark green, identical to the best seedlings on severely burned blocks (Plate XXI). Hemlock foliage had the best colour on unburned blocks, and the worst on severely burned ones, where no seedlings were dark green i n colour (Plate XXI).  Salal site produced the highest per cent of pale seedlings.  Redcedar showed the most discoloration.  Only moderately burned  Salal blocks produced some dark green seedlings (25 per cent).  The typical  discoloration on Salal site severely burned blocks and on the Swordfern site unburned blocks was the most conspicuous i n the experiment.  The pale seed-  lings had a purplish rosy t i n t , sometimes changing into whitish gray colour (Table XVI, Plates - XXIII, XXIV).  - 59 Stimulated Winter Growth, April 20, 1961 The stimulated growth replaced the natural spring growth (Figure 1 8 ) . On April 20, 1961, 90 per cent of the Douglas-fir seedlings had buds, and a number of them were bursting again for the second growth.  Hemlock and red-  cedar seedlings were i n continuous growth u n t i l the end of May (Figures 2 5 , 26).  The growth of Douglas-fir seedlings, i n one month period of stimulated  growth, showed values from 27 to 36 per cent of the previous integrated growth.  Only the unburned control Salal site was higher with 41 per cent.  Low results were shown on the Moss site (28 to 30 per cent) and the over-all average of growth was 33 per cent for Douglas-fir. Western hemlock i n a six-week period had averages from 27 to 3 4 per cent, except the lowest 20 per cent on the severely burned Salal site, and the high values on the unburned control blocks, from 40 to 52 per cent. Average for hemlock was 3 4 per cent. Western redcedar in a two-month period had a wide range of increase from 24 to 60 per cent, both extremes on severely burned blocks. crease on the Moss site averaged at 53 per cent.  Its i n -  Average for the growth with  redcedar was 43 per cent of the previous year's growth. Unburned blocks showed higher values of growth i n the second year than the burned blocks for both hemlock and redcedar.  The severely burned  Salal site blocks had the lowest per cent of growth with hemlock and redcedar (20 and 24 per cent). Redcedar had the highest increase and Douglas-fir the lowest, on both Swordfern site and Moss s i t e .  On the Salal site the sequence was  reversed. The changing values of growth i n the second year had l i t t l e effect  SWORDFERN SITE S M U  60 _  MOSS SITE S M U  SALAL SITE S M U  •I  DOUGLAS-FIR 40 20  WESTERN HEMLOCK  J  -in  0 ,60 u , i i  40  T—  I  20  X  0 WESTERN REDCEDAR  60 " 40 -I 20 0 _  FIGURE 18. HEIGHT OF TWELVE - MONTH - OLD SEEDLINGS AT THE END OF THE STIMULATED GROWTH, APR, 20,1961. AVERAGE OF THREE SEEDLINGS IN EACH BLOCK AND OF TWELVE FOR EACH GROUP. SEE CHART OF SYMBOLS.  - 60 on the sequence of productivity, which remained consistent except with hemlock, which changed places between the severe and control blocks on the Salal site and a l l treatments on Moss site blocks (Plates - XVIII to XX). Second Spring Growth, June 25, 1961 The spring growth i n the experiment replaced the usual summer growth in nature, though i n a restricted manner.  Final measurement of seedlings on  blocks took place when the Douglas-fir seedlings developed their second bud i n June, 1961. Hemlock and redcedar seedlings had no conspicuous rest period after the provoked bud bursting.  Some Douglas-fir seedlings after their rest  i n April did not start a new growth. On the Swordfern site unburned control blocks, 92 per cent of a l l seedlings did not commence second growth.  Three severely burned blocks and  one moderately burned block each had one slow seedling with average size (25 and 8 per cent). On the Moss site, 16 per cent of seedlings on severely burned blocks and control blocks, and 25 per cent on moderately burned blocks had slow seedlings.  Here the severely burned group was the worst. Nearly a l l seedlings on Salal site blocks started a second growth  except 8 per cent on the severely burned and unburned blocks.  These were  both of below average growth. On the average, 22 per cent of a l l the 108 Douglas-fir seedlings did not burst for the stimulated second growth, with the highest value on the Swordfern site (41 per cent), and the lowest on the Salal (5 per cent). Figure 19 presents the average height of the three seedlings on each block.  Plates XXII to XXIV show examples of discoloration caused by  FIGURE 19.  HEIGHT OF FORTEEN - MONTH - OLD SEEDLINGS AFTER SECOND SPRING GROWTH, JUNE 20 1961. AVERAGES  AS BEFORE. SEE CHART OF SYMBOLS.  - 61  nutritional deficiency. Despite the reduced growth rate of the best growing seedlings (e.g. on severely burned Swordfern blocks), the over-all sequence of productivity by treatment did not change.  The sequence of height values approached the  final pattern of productivity i n a l l respects. The f i n a l order of decreasing productivity developed for a l l three species was as follows: Swordfern site: Moss site: Salal site:  severe - moderate - unburned unburned - moderate - severe moderate - unburned - severe  Size and Weight of Harvested Seedlings, July, 1961 By the f i r s t week i n July, 1961, a l l seedlings gradually turned to a resting stage.  Douglas-fir and hemlock developed buds on a l l their growing  tips and redcedar formed i t s densely scaled pseudo-buds. Figures 20 and 21 present the average size of shoot and root for the three seedlings of each block.  Tables X, XV, and Figures 22, 23 show the  fresh and dry weight of the two parts and the whole plant.  The moisture con-  tent and the shoot/root ratio were calculated from these values.  Plates XXV  to XXX present concluding pictures of the experiment. The productivity of each s o i l block i s expressed as the total ovendry weight of the three harvested seedlings from each block.  The computed  total for each group gives the total weight of twelve seedlings on the four replicas.  Both fres"h and dry weight values showed a uniform sequence with  the height. Statistical comparison was made on final results of production for a l l combinations of variants, by both the size of seedlings and weight of  ROOTS ON REMOVED SEEDLINGS,  JULY 8,1961.  to f o l l o w  page  61  to follow page 61  FIGURE 20.3.  SALAL  SITE - LENGTH OF SHOOTS AND ROOTS  ON REMOVED SEEDLINGS, JULY 8,1961.  to follow page 6  SWORDFERN SITE  D  60  SMU  H-C SMU SMU  M O S S SITE  D  SMU  H  C  SMU SMU  SALAL SITE  D  SMU  H 'C  SMU SMU  .50 '40  J  x 30 o  :  . UJ x  20 .10  SHOOT o ROOT 10 20 30 40 _: o  •r 50 60 70 80 _I UJ  90  ;  FIGURE 21.  GROUP AVERAGES OF SHOOT - AND ROOT - LENGTHS BY TWELVE SEEDLINGS IN EACH SYMBOLS.  VARIANT . SEE CHART OF  o o —  o FIGURE  22.1.  SWORDFERN  SITE -  SEEDLINGS REMOVED  TOTAL DRY SHOOT - AND ROOT - WEIGHTS OF THREE FROM EACH BLOCK. THE TETRAMEROUS  NOTE WEIGHT OF TWELVE SEEDLINGS  FROM  FOUR BLOCKS.  COLUMNS DE-  ~o Q ID  MOSS  SI TE  -  TOTAL DRY SHOOT - AND ROOT - WEIGHTS OF REMOVED  SEEDLINGS. SEE PREVIOUS FIGURE.  o o o  FIGURE 22.3.  SALAL  SITE  SEEDLINGS. SEE  -  TOTAL  DRY SHOOT  PREVIOUS FIGURE-  AND ROOT - WEIGHTS OF REMOVED  TJ  D  IQ  A  CO  to f o l l o w  SWORDFERN SITE  D  SMU  H  C  SMU SMU  I  MOSS SITE  D  SMU  H  C  SMU SMU  page  SALAL SITE  D  SMU  H  C  SMU SMU  160 _ 140 J 120, J 100 J co  80 _  < cc o  60 o  40  UJ  »_:20 o o  X COQ  O §20 40  "  60 J  FIGURE  23  SUMMARY FOR  OF SITE -AVERAGES (FROM  SHOOT - AND ROOT - WEIGHTS.,  TABLES 22-1,2,3)  to f o l l o w  SW ST  D H C  D  M ST H G  page  61  SL ST D.JH  C  75 50 J 25 j  UNBURNED BLOCKS FOREST PLOTS  j  80  COMPARISON OF SIZE AND WEIGHT OF SEEDLINGS FROM UNBURNED CONTROL BLOCKS AREA.  AND OF NATURAL SEEDLINGS IN THE SAMPLED  EACH COLUMN REPRESENTS TWELVE SEEDLINGS.  - 62 crop on blocks (Appendix II and Table XXXII). The total dry weight of the seedling crop best represents the results of treatments.  In most cases the tests of significance based on stem  height agree with those based on weight.  Only on the Moss and Salal sites  did hemlock and redcedar have divergent values i n the levels of significance when treatments were compared by height and by weight. Statistical evaluation showed the following differences for the crop of dry material on each site and for each species by the differences i n treatment (Figure 27): 1. Swordfern site.  The production on both severely and moderately  burned blocks was highly significantly larger than that on unburned control blocks.  There was no significant difference between the production of two  burning rates, moderately burned blocks being close to those severely burned. A l l three species had similar results i n the s t a t i s t i c a l analysis. 2.  Moss site.  The production on both severely and moderately burned  blocks was highly significantly smaller than that on unburned control blocks with Douglas-fir, and significantly smaller with western hemlock.  There was  no significant difference between the production of the two burning rates, severely burned being the lower. ference.  Western redcedar had no significant dif-  Its values, however, showed the same sequence as the other two  species. 3. Salal site.  The production of moderately burned blocks was sig-  nificantly higher than that on the severely burned blocks with both Douglasf i r and western hemlock. ference.  Western redcedar had a highly significant dif-  There was no significant difference between the production on un-  burned and burned blocks, the unburned blocks being between the two burned variants.  - 63 The water content of plants was expressed as percentage of dry matter and presented for the groups i n Table XI. The data was not instructive because of the various moisture content i n blocks at the time of harvesting. Especially water content i n roots was extremely various. There was some indication that Douglas-fir and hemlock had lower water content than redcedar. No significant consistency was shown i n the water content by treatment, though the severely burned variant had the highest averages. Generally roots contained twice as much water than aerial organs with Douglas-fir and western hemlock; and more than twice as much with western redcedar. The total dry production i n grams and the water content for each species averaged as follows: dry weight Douglas-fir western hemlock western redcedar  water content  water per cent of dry weight  2042.68  3779.14  2139.02  3 8 3 5 . 4 4  180  1753.18  4 4 2 1 . 1 2  2 5 1  5934.88  12035.70  203  Average  1 8 5  The average seedling weight for Douglas-fir was 18.9 g.; for hemlock, 19.7 g.J for redcedar, 16.2 g.; and the average for a l l three species, 18.3 g. The three kinds of shoot/root ratio are compared i n Table XII. On the Swordfern site, the smallest seedlings have the highest values; on the Moss site the tallest seedlings have the highest values. they are on unburned blocks.  In both cases  On Salal blocks again the best seedlings had  the highest values; i n this case on moderately burned blocks.  The range of values of shoot/root ratio is very wide and irregular, as follows:  Shoot/root ratio by length  by fresh weight  by dry weight  Douglas-fir western hemlock western redcedar  0.41, 0.56, 0.27,  0.93 0.94 0.70  1.04, 1.64 1.41, 2.09 1*71. 2-54  2.04, 2.58 2.65, 3.41 1.4?, 3-75  Total  0.27.  0.94  1.04.  1.49.  2.54  3.75  Based on data by dry weight, the shoot/root ratio had generally highest values on unburned blocks and lowest values on severely burned blocks, regardless of the productivity rate.  This fact i s shown on Figures 22 and 23  also, where the proportion of roots to aerial organs appears highest i n unburned group and lowest on severely burned groups.  Generally Douglas-fir  showed the smallest S/R ratios, which indicates that i t needed the largest root system as compared to i t s aerial organs.  Hemlock was the opposite i n  this experiment. Phases of Seedling Growth The growth periods distinguished i n this study refer to phases started by bud bursting and ending by formation of a new bud (Table XVI). 1.  Douglas-fir seed was sown on April 9, I960.  April 13 and was completed by April 20.  Germination began on  I n i t i a l growth was finished by the  end of June for 60 per cent of the seedlings on unburned Swordfern site blocks (33, 37, 40). By the middle of July a l l seedlings were dormant for one or two weeks after which they burst again into a summer growth (Lammas growth).  The summer growth on large seedlings continued u n t i l the end of  August, when gradually up to September 10 a l l the largest seedlings formed buds.  From August 18 to September 23 a moderate amount of a r t i f i c i a l light  to follow p a g e 64  50  SEVERELY BURNED  DOUGLAS-FIR 40  1  30  20  MODERATELY BURNED 10  UNBURNED-CONTROL  0_  SEVERELY BURNED  WESTERN HEMLOCK 40  j  2  O  30  x  2  LU X  MODERATELY BURNED  20 10  UNBURNED-CONTROL  0_  WESTERN REDC :DAR 40  J  SEVERELY BURNED 30  1 MODERATELY BURNED  20 10  j  UNBURNED-CONTROL MONTH PERIOD  N INITIAL  SUMMER-  M REST  1961  M  STIMULATION SPRING  FIGURE 25.1. SWORDFERN SITE. PERIODIC GROWTH OF SEEDLINGS IN THE ..EXPERIMENT.  ' to follow page 64 UNBURNED-CONTROL  50 MODERATELY  BURNED;  40 : -30 1 SEVERELY  20 J  io  BURNED  i  oJ, WESTERN  HEMllOCK  UNBURNED-CONTROL, MODERATELY B  -40 2  ° 30 i  j—  SEVERELY  o 20  BURNED  Ui X  10  d  o. WESTERN  REDCEDAR  UNBURNED-CONTROL  40 30  ;  20  j  MODERATELY B  FIGURE 25.2. MOSS SITE. PERIODIC GROWTH OF PERIMENT.  SEEDLINGS IN THE EX  to follow page 64  5  0  "J  40  1  .30  :  DOUGLAS-FIR  MODERATELY BURNED  UNBURNED-CONTROL  .20 SEVERELY  10  BURNED  0_ MODERATELY BURNED  WESTERN HEMLOCK 40  J  UNBURNED-CONT  2  o 30  o 20  SEVERELY BURNED  10  MODERATELY BURNED  WESTERN REDCEDAR 40  1  UNBURNED-CON1  30 20  SEVERELY BURNED 10 1 N  MONTH PERIOD  INITIAL  FIGURE 25.3.  SALAL  SUMMER SITE. PERIODIC  PERIMENT.  REST  1961  M STIMULATION  M |J SPRING  GROWTH OF SEEDLINGS IN TE EX'  to follow page 64  MODERATELY  BURNEC  UNBURNED-CONTROL  FIGURE  26.  AVERAGE FOR  EACH  OF  PERIODIC SITE-  GROWTH  OF  THE THREE  SPECIES  R G U R E  27.  RELATIVE EACH  DRY  WEIGHT  PRODUCTION  COLUMN REPRESENTS  SITE D E N O T E S  WEIGHT  TOTAL  OF TWELVE  DRY  FOR  EACH  WEIGHT  SPECIES OF  IN  TWELVE  NATURAL SEEDLINGS  FROM  EACH  TREATMENT ON  SEED LINGS, [FOURTH EACH  SAMPLED  ALL ROWINTACH  AREA.  - 65 was added, with the result that 35 per cent of the largest seedlings on the severely burned Swordfern blocks (5, l ) and 70 per cent of the largest seedlings on the four unburned Moss blocks grew throughout September.  Sixty per  cent of the smallest seedlings on unburned Swordfern blocks (33, 37, 40) also continued growth i n September, but by the end of December a l l seedlings were dormant. Douglas-fir seedlings burst last of the three species i n the seventh week of a r t i f i c i a l light i n the last third of March.  (The a r t i f i c i a l light was  on from February the 9th u n t i l May 5, for 85 days.).  By the middle of A p r i l ,  1961, a l l seedlings; except those on unburned Swordfern blocks and except one on unburned Salal block (49), developed terminal buds which soon burst for the second growth period of the second year.  The last growth i n the experiment  ended by the end of June, when a l l seedlings developed terminal buds. Based on the march of growth of Douglas-fir seedlings, the following distinctions developed:  (a) the severely and moderately burned Swordfern  blocks and the unburned Moss blocks supported five growing phases during the sixteen months of the experiment, a l l of which ended with terminal bud formation; (b) the severely and moderately burned blocks of Moss site and a l l three variants of Salal site supported four phases of development, the third late autumn growth of the former group being absent; (c) the unburned Swordfern blocks, supporting the weakest seedlings i n the experiment, showed only three growing phases, two i n the f i r s t year and one i n the second.  On the graphs  of Figures 25-1 and 2 the third phase does not appear i n September and October, I960, i n curves for burned variants on Swordfern and for unburned on Moss site, because there was such a small growth spread over a long period of time that i t could not be shown graphically.  2. Western hemlock seed was sown on April 9, I960, and germinated from April 15 to May 1.  On May 5 a supplementary planting of 3 per cent was added,  but these seedlings were later eliminated by thinnings, so they did not affect the results.  Hemlock was the only species i n which seeds continued to ger-  minate for eight months. The growth of hemlock was continuous u n t i l December, I960. There was reduced growth i n August, but no terminal bud formation at that time. Only the smallest seedlings formed terminal buds on unburned blocks, i n the following proportions:  on the Swordfern site blocks (38, 35), 25 per cent of  a l l seedlings produced terminal buds; Moss site block 20 with one seedling, 5 per cent; and Salal site blocks (35, 31) 45 per cent of seedlings.  These  small seedlings mostly burst for a second growth i n September, except for 15 per cent of the smallest ones on Swordfern (38, 35) and on Salal (41) blocks. Hemlock seedlings responded by the f i f t h week after the onset of a r t i f i c i a l light, bursting a l l terminal buds from March 10 to 20.  The growth  in the second year was continuous u n t i l the end of May when a l l seedlings developed terminal buds. In hemlock seedlings, three phases of growth were recognized during the experiment, but only with two terminal bud formations.  Less than half  of the small seedlings on unburned blocks formed terminal buds between the two growth phases i n the f i r s t year.  The inferior production of hemlock seed-  lings on unburned blocks.in the f i r s t year i s apparent i n Figures 25-1, 2, 3. 3. Western redcedar seed was sown on April 10, I960, and germinated from April 17 to 20.  Because of the low germination, 50 per cent additional plant-  ing was necessary on May 5, to guarantee ten seedlings per block. No  - 67 difference was observed i n the subsequent individual development of original and transplanted seedlings. Three periods of growth were distinct on redcedar seedlings by their height measurements; two i n the f i r s t year, and one i n the second.  Instead  of the usual scale-coated bud, western redcedar develops for i t s resting period only sturdy tips with a dense cluster of needle scales.  Such pseudo-  buds, representing dormancy, developed on a l l seedlings by January, 1961. Few seedlings showed pseudo-buds at the end of August, I960, except those on the severely burned blocks of the Moss site where 5 to 10 per cent of the seedlings had such resting t i p s .  The Salal blocks, where redcedar had the  best height growth, showed an average of 80 per cent with pseudo-buds on September 9, I960.  Furthermore, 80 per cent of seedlings on moderately  burned Salal blocks had such tips, and these seedlings were the tallest for redcedar at that time. Western redcedar seedlings were the f i r s t to break dormancy, as soon as i n the f i r s t week after the illumination, and by February 10 to 20 a l l seedlings had new slender-growing tips.  After a more or less continuous  growth u n t i l June, the resting tips appeared again on most seedlings. 4. Based on average height of seedlings computed for sites and species in each group of treatment, a set of curves of growth was constructed (Figures 25-1, 2, 3 and 26).  The curves show four periods of growth with a  three-month resting period i n winter.  The first-year spring growth and  summer growth correspond to the usual seasonal periodicity of growth. These two periods were divided i n most seedlings by a bud which remained for a one- to two-week period. Breaking of the dormancy pushed forward spring bursting to February  - 68 and created an a r t i f i c i a l period of growth until about the end of April when Douglas-fir developed terminal buds, resting for a week or so.  Hemlock and  redcedar grew uninterruptedly until the end of June when they entered into a resting state that concluded the experiment. The curves represent a uniform effect of treatment within each site for a l l species.  This consistency within each site suggested the construc-  tion of a summary graph (Figure 26). On the Swordfern site, the height growth was always lowest on unburned blocks for a l l species.  The growth was highest on the severely burned  blocks and mediocre on moderately burned blocks.  Only redcedar had the best  growth on moderately burned blocks u n t i l the middle of the summer of I960 (Figure 25-1). On the Moss site, Douglas-fir and redcedar showed the following order: burned.  highest, unburned; mediocre, moderately burned; lowest, severely This sequence was shown by hemlock also i n the second year.  Hemlock  had i n the f i r s t year lowest growth on unburned blocks* (Figure 25-2). The Salal site showed the least consistent trend, where only the moderately burned blocks consistently showed the highest height growth.  The  severely burned blocks surpassed the unburned blocks during the f i r s t summer with Douglas-fir and redcedar.  Hemlock had the lowest results with unburned  blocks u n t i l the period of stimulated growth (Figure 25-3).  Severely burned  blocks dropped their growth with hemlock at the spring of the second year, as i n the Moss site. The integrated growth of a l l species for each site showed a consistent order of growth, except on the Salal site where the severely burned blocks had higher values than the moderately burned blocks u n t i l the spring  - 69 of the second year (Figure 2 6 ) . Changes of Sites by Modified Conditions At the conclusion of the experiment i n June, 1961, ninety-four second-year natural seedlings were l i f t e d from the vicinity of sample ditches (Plate - XVII).  The seedlings were measured and weighed i n a uniform fashion  to those i n the experiment (Tables XIII, XIV). The gravimetric values were computed for twelve seedlings to get comparable values to those i n the experiment.  Their comparison to experimental results i s presented i n Table XV  and Figure 24. Comparisons of seedling production i n the field and on unburned blocks i n the greenhouse showed an increase i n dry weight due to the greenhouse conditions.  While the increase with the Swordfern site averaged nine  times, i t averaged 483 times with the Moss site. The length of one-year-old wild seedlings i n this collection was larger than those reported i n literature, but equal to those i n the experiment.  Franklin (I96l) reported an average of 40 mm. length for Douglas-fir  (range - 20 to 85), and 18 mm. for western hemlock (range - 10 to 25). Table XIII shows for Douglas-fir an average of 48 mm. (range - 44 to 60), and for hemlock 31 mm. (range - 21 to 43). The shoot/root ratio by dry weight fluctuated between 1.84 and 3.39, being as inconsistent as those i n the experiment.  The highest values  were shown by redcedar (3*71, 6.31, 3.39) and the lowest ones by Douglas-fir (1.84, 2.23, 1.85). In nature, Douglas-fir forms proportionally the smallest aerial matter to the root, and redcedar the largest.  The latter does not  need such a large root system to develop a large crown i n a seedling.  - 70  In the experiment, Douglas-fir revealed the same proportion of root system. Western redcedar developed proportionally larger roots i n the experiment than i n nature, but western hemlock formed smaller roots i n the blocks than i n the forests. Since the unburned control blocks were watered only with d i s t i l l e d water and kept i n the greenhouse, i t i s obvious that only the changes i n the environment could be responsible for the above increased plant production. The following conditions were changed for a l l three sites:  mild  and continuous temperature, moisture and light was introduced to prolong the growing season, and probably an increase i n the organic l i f e i n the s o i l . The high snow cover causing saturation with cold water, and the mid-summer desiccation period were excluded by regular i r r i g a t i o n . In reverse to the above beneficial effects, only the Swordfern site was damaged by disruption of i t s major nutritional supply, the lateral seepage of water.  The Swordfern site enriches i t s s o i l with nutritional  solution from overlying rich organic remains (Krajina).  In the experiment,  on the contrary, instead of a natural continuous enrichment, the watering with d i s t i l l e d water gradually depauperated the s o i l blocks by vertical leaching. The other two sites with richer organic remains i n raw humus could have had an increased decomposition and biological l i f e , and from the presence of nutrients which would normally be carried away by lateral seepage. Especially hemlock on the Moss site benefited from the organic nutrients. Douglas-fir, being more dependent on nitrates than on the f i r s t products of decomposition, had less increase than the other two species. The Swordfern site had the lowest increase of a l l (9 times),  because of i t s loss of lateral seepage, especially for Douglas-fir only 3.4 times.  The loss by lateral seepage was l i k e l y offset by the increased micro-  bial activity and other listed advantages of the greenhouse conditions (Table XV). The new experimental conditions formed new semi-artificial sites, which do not occur i n nature.  "Hydroponic" effects were ceased for the  Swordfern site, and a general increase i n decomposition was introduced which especially enriched the Moss site. This experiment provided evidence that natural sites cannot be taken into a greenhouse without changing them.  It was also seen that the  initiated changes would proceed i n each case i n a special direction. Chemical Soil Properties Tables XVII - A,B present s o i l samples used for analysis. samples from 1959 represent average layers of each s o i l type.  Field  There i s no  perfect uniformity between the field s o i l samples and the individual s o i l blocks, nor between the s o i l sample blocks and seedling blocks.  There is a  fair similarity, however, between the samples taken from each block at the commencement and the conclusion of seedling growth i n I960 and 1961 (Plates XIII - XVI). Despite the above difficulties, there was a f a i r consistency i n the productivity of variants for a l l species, and also a f a i r relationship of s o i l properties and their changes to the productive capacity of the corresponding seedling blocks.  The treatment with the largest crop showed best  nutritional potential i n many s o i l properties (Table XXXI and Figure 28). In some cases the quantity of a nutrient was related to the productivity;  - 72  in others the change of some values i n the succeeding years or the deviation which was apparent between the treatments were correlated with differences i n productivity. A l l s o i l samples were analyzed i n two replications from May 9 to July 7, 1961. In addition, selected seedling blocks of average productivity were examined for pH values from each combination.  For the final evaluation,  the value of the upper surface layer and the average of the whole system were used (Table XXVI).  For each layer the average of the two results from the  analysis was used, and the block average was computed i n proportion to the thickness of each layer. Soil pH Soil pH values are presented i n Tables XVIII - A,B,C.  The field  values (1959) averaged 5.18 for the Swordfern site, 4.68 for the Moss site, and 3.60 for the Salal s i t e .  There was a remarkable increase downward, which  was especially large i n the Swordfern site (5.55). The general trend i n the s o i l pH, as compared to field values, i s shown for unburned blocks as follows: I960  1959  I.  Swordfern site:  II.  Moss site:  III.  Salal site:  series:  field  surface block  4.60  surface block surfac e block  1  1961 2  1  2  5.30 5.56  4.85 5.48  5.25  5.30  3.45  4.10  4.18  4.25  4.75  3.60 3.60  3.75  4.20  4.00  4.28  5.18  4.68  4.94 3.72  4.75 4.07  5.47  4.99  4.16  5.88  5.26  4.37  There is a change to higher values with time as a result of greenhouse conditions which encouraged decomposition.  Only the Swordfern site  - 73 showed a slight decrease i n the f i r s t series i n 1961. Burning usually also decreased acidity.  On the humus-less Sword-  fern site moderate burning raised these values more than the severe burning in the sample of the f i r s t block series.  On the Moss and Salal sites severe  burning always raised the pH more than on moderate burn. surface were higher than i n the lower layers.  The changes i n the  Only the Salal site on i t s  severely burned block surface had a decrease of -.10. The above results provide further evidence that f i r e increases s o i l pH, and that moderate burn results i n a higher increase than severe, i n soils without organic accumulation.  The ashing of organic matter and the decomposi-  tion of s o i l minerals by heat can reduce acidity (Lutz, 1956; Forest Soil  Comm., 1957). Tarrant (1953 and 1954) stated that heat i n the range of 600° to  900°F (300° to 500°C) changes pH, but higher temperatures do not result in further changes.  He found significant differences between the changes of pH  of unburned, slightly burned, and severely burned s o i l s .  The unburned had  an acidity of 4.4, the slightly burned was lowered to 7.1, and the severely burned to 7.2, for both undisturbed forest soils and clear-cut areas i n the Douglas-fir Region.  He noted:  "Highly acid s o i l can better withstand  chemical effects of burning." Uggla (l958^a) i n Sweden reported an increase of 2 to 4 pH values in the F layer, which by three and a half months later had decreased again by 0.6 value.  Six years later, the pH value of the H layer was higher than i n  the F layer. Metz and his co-workers (1961) observed i n North Carolina the following changes of pH values:  from 4.2 to 4.3 and 4.8 i n the upper two-inch  - 74 layer; and from 4.5 to 4.6 and 4.7 i n the two- to four-inch layer.  Beaton  (l959 b) found an increase i n the 0 horizon by 2.4 values. ;  The Ahlgrens (i960) listed twenty-one authors reporting different decreasing changes i n s o i l acidity after f i r e .  They found only five publica-  tions which reported no significant change i n acidity after forest f i r e s . Table XIX gives values of s o i l pH from the 1961 samples of the s o i l blocks and compares them to the corresponding values of the average seedling blocks at the same time. There i s a consistent and highest increase i n s o i l pH with the Douglas-fir blocks especially i n the Moss site (+.94)•  The average with  Douglas-fir was a 0.60 increase, versus 0.15 increase for the other two species. Plotting s o i l pH against burning rate, the highest increases by root effect are shown on severely burned surfaces and the lowest on the moderately burned ones.  The relationship i s consistent for the block  averages only with the Salal s i t e .  From the unburned blocks, Swordfern pro-  duced the highest average pH increase, despite the smallest seedling growth there.  On the Moss site, on the contrary, the most productive unburned  blocks showed the lowest increase i n pH, due to seedling roots. In relation to mild conditions i n temperature and s o i l moisture, Waksman asserted (1936) that CO,, production i n the s o i l atmosphere increased with the increase of temperature up to 32°G (90°F). ship of changes i n pH and  Straight-line relation-  (oxidation - reduction potential) was recently  emphasized also by Starkey (1959). The increase i n s o i l pH by burning, by greenhouse effect and by the presence of plant roots was a result of various changes such as increased  - 75 decomposition of s o i l minerals, the ashing of organic remains, and increased bacterial l i f e (Lutz, 1956).  In this experiment the amount of ash was i n s i g -  nificant i n comparison with natural conditions, where large masses of wood material are incinerated. Wilde (1958) stressed the chelating effect of organic anions produced by root excretion (e.g. carbonic acid) and sloughings of epidermal tissues.  Increased activity i n s o i l was assumed by Starkey (1959), who also  stated that the changes i n pH and  may be influenced by organic matter  originating from roots and other microbial products, called the rhizosphere effect. Cation Exchange Capacity Cation exchange capacity (T) i s reported i n Tables XX and XXVI. The changes by time and the deviations by burning rate are shown in Tables XXVIIIand XXIX.  The values generally decreased with time, with the exception  of a slight increase on Swordfern site unburned block (+1.48), and a large increase (+6.32) on the severely burned Moss site.  The changes i n cation ex-  change capacity were inversely related to pH values and to the productivity. The largest decreases on the severely burned Swordfern site block (-3.42) and on the unburned Moss block (-2.90) were accompanied, i n both cases, with highest productivity; low production was shown with a pronounced increase on unburned Swordfern (+1.48) and on severely burned Moss blocks (+6.32). The same consistency was valid for the Salal blocks (best - 3-75, lowest - 13*07)* The lowest values of cation exchange capacity were found with the eluviated layer (Ae), especially i n the Moss site (8.78 me/100 g.), and the highest starting values (76.00 me/100 g.) were i n the Moss site, both i n the f i e l d sample.  - 76 The moderate burning always resulted i n a decrease of the cation exchange capacity i f compared to those of unburned blocks i n both years. Severely burned blocks, however, were not consistent i n this respect, showing values greater than the unburned blocks, e.g. Swordfern site i n I960 and Salal site surface i n 1961. Tarrant (1956,b) asserted that light burning had no appreciable effect on base exchange capacity, but severe burning strongly reduced i t . Wilde (1958) stated that base exchange capacity is closely related to the content of ligninlike substances.  Raw humus has a base exchange capacity  from 40 to 100 m.e. per 100 g.j mull humus seldom more than 30; and that of the pure organic matter may exceed 200 m.e. per 100 g.  This fact implies  that any destruction of organic matter w i l l result i n lower base exchange capacity.  Lutz and Chandler (1946), referring to Robinson (1936), pointed  out that organic colloids have a base exchange capacity of about 250 to 450; whereas inorganic colloids have only 16.4 to 110,2 m.e. per 100 g.  Tryon  (1948) stated that hardwood charcoal increases, but coniferous charcoal decreases, the base exchange capacity. Lutz and Chandler (1946) stressed the direct correlation between the fineness of clay particles and the cation exchange capacity and believed that broken oxygen bonds may play a role i n i t s changes.  We can conclude  that excessive heat probably so changed the fineness of clay particles that the change resulted i n a decrease of exchange capacity.  Tarrant and Wright  (1955) observed larger height growth of Douglas-fir seedlings after burning on clay loam s o i l than on sandy clay loam; both being larger than the growth on unburned s o i l .  The authors did not find explanation for the differences.  Perhaps the change of cation exchange capacity, related to clay content,  - 77 was responsible. Major Exchangeable Cations and Their Saturation From the basic cations such as hydrogen, calcium, magnesium, potas++  -H-  +  sium, sodium, aluminum and iron, the three metals - Ca , Mg , K - were studied i n this experiment (B), and expressed i n m.e. per 100 grams of s o i l (T).  Base saturation for these three cations was expressed, I [  g  _  B  x  _  | | _^  Exchangeable cations of Ca Mg K  T  x  cation exchange capacity  '  and presented i n Tables XXI, XXII and XXVI. There i s no consistency i n the changes of the three detected nutrients; a general trend with their computed values, however, can be seen.  The  sum of the cations of three nutrients increased with time i n the Swordfern site sample, and decreased i n the other two site samples for both the surface and block values.  This difference can be explained by the more effective  burning i n the mineral layer of Swordfern site.  The mineral horizons of the  two other soils were only slightly affected by burning, because of the presence of a protecting organic accumulation. There was no consistent relation found between the amounts of exchangeable cations plotted against the burning rate.  These were somewhat  higher on the most productive unburned Moss variant and on the moderately burned Salal variant than on other samples or i n the corresponding f i e l d samples.  Swordfern site had the highest values i n the field sample, followed  by the low-productive unburned variant. The saturation of the three elements had a direct bearing on product i v i t y , and a direct parallelism with s o i l pH. Its marked changes by both rate of burning and time followed i n many cases the productivity (Tables  XXVIII and XXIX). The increase of base saturation of calcium, magnesium and potassium was highest on the severely burned Swordfern block and on unburned Moss block; both the most productive variants in their group.  This was true i n the  second year with the surface of the Swordfern and Moss sites; and i n both years (i960 and 196l) with both sites for their entire blocks. saturation with Salal site was detected on the surface i n 1961.  The highest For the en-  tire block i t was equal in both years. Within each treatment (Table XXXI), an increased saturation accompanied highest production on severely burned Swordfern and unburned Moss site blocks.  The lowest saturation was also indicative of lowest production, e.g.  severely burned Moss and Salal site blocks. The concentration of calcium and potassium i s generally believed to increase after fire (Ahlgrens, I 9 6 0 ) , due to the remaining ash.  Pickering  (1910) found increased solubility of salts i n s o i l affected by heat lower than 100°C. elements.  Magnesium has not been studied well i n comparison to other In this experiment there was less increase observed i n these three  bases, because of the absence of considerable ash supply.  The total amount of  bases (B) generally was decreased by burning (Table XXVI), except i n the surface layers of the Salal site blocks where i t was increased by the burning. In this experiment the increased saturation of the three metal cations was due to the strongly reduced base exchange capacity, which was more easily saturated by even a smaller amount of bases than their original higher exchange capacity. Overstreet and Dean (1953) quoted Jenny and Ayres, who i n 1939 attempted to correlate the availability of cations of potassium, sodium and  calcium with their equivalent percentage i n the exchange complex of the s o i l , that i s , with the degree of saturation.  This procedure resulted i n more  satisfactory correlations than the earlier attempts when the availability of an ion was correlated with i t s concentration i n the exchange complex. Phosphorus The available phosphorus, expressed i n p.p.m., i s presented i n Tables XXIII and XXVIj and i t s changes i n Table XXX.  Its values generally  increased with time, except on the severely burned Salal block where i t decreased remarkably (-20 p.p.m.) i n the block profile.  On the surface, how-  ever, decrease was shown not only i n Salal blocks, but also on the two burned Moss blocks and moderately burned Swordfern block. The changes with time and burning rate showed the following relationships to the productivity (Table XXXI).  On the Swordfern site the  largest increase by the severe burning (166.6 per cent) was associated with the highest productivity, and the lowest value of 3 p.p.m. with the lowest productivity.  On the Moss site i n the change with time the largest increase  on the surface i n Moss block was associated with the highest productivity, +12.9 per cent.  In the block value the lack of any increase was accompanied  by the lowest crop on the severely burned block.  In the deviation by burn-  ing, the maximal difference of severely burned blocks resulted i n the lowest productivity (-5 p.p.m.).  On Salal blocks maximal change was recorded with  time on the moderately burned, most productive block, and by the rate of burning, the highest and lowest values also followed the same sequence i n productivity. The above results show that the changes of available phosphorus by treatment and time have, i n most cases, direct correlation to the s o i l pH  - 80 and  the production of the corresponding seedling blocks. It i s generally thought that phosphorus content i s increased after  a forest f i r e .  Isaac and Hopkins (1937) could not find any increase, nor did  Fowells and Stephenson (1933). Lutz (1934 and 1956), on the contrary, found an increase i n New Jersey and Alaska but observed no increase in the Pitch Pine Region.  Similarly, Vlamis et a l . (1955) found a marked increase of  phosphorus i n ponderosa pine sandy loam, but no significant change i n loam. LeBlanc (1956) could not find any change i n phosphorus content i n Quebec spruce s o i l s .  Tarrant (1956,b), however, reported a general increase of the  acid soluble F^Ojj ^  r o m a  H burned areas.  Kivekas (1939), Tryon (1948), Lunt  (1951), Austin and Baisinger (1955), Uggla (1958b) a l l report an increase of this important element.  Beaton (1959ib) found insoluble calcium compounds  which decreased the availability of phosphorus.  The Forest Soil Committee of  the Douglas-fir Region (1957) reported improved availability of phosphorus by increase of s o i l alkalinity. Organic Matter and Nitrogen Both the organic matter and nitrogen revealed an i n i t i a l decrease from their f i e l d values and the burned blocks from their values on the unburned variants.  Only surface layer of the Salal site blocks had an i n i t i a l  higher content of organic matter (Tables XXIV, XXV and XXVI).  Organic matter  per cent usually decreased by time, except on unburned and moderately burned Swordfern blocks.  Severe burn resulted i n heavy loss of organic matter, even  in the second year. Neither the per cent values of organic matter nor of nitrogen showed f u l l y consistent correlation to the productivity of the corresponding variants.  Only the highest contents on the severely burned Swordfern and on  - 81 the unburned Moss were correlated with the highest production of these variants. The ratio of the per cent organic matter to the per cent nitrogen did not show a consistent relationship to the productivity except again on the Swordfern site.  Severe burn on the Swordfern site resulted, i n 1961, i n  the largest decrease of this ratio associated with high production, and the highest increase on the severely burned Moss site did the reverse.  Nitrogen  did not appear to be a c r i t i c a l factor of the seedling development i n this experiment, except on the control unburned Swordfern blocks versus the severely burned variants of the same site. The change of nitrogen concentration on unburned blocks and i t s relation to the f i e l d conditions with nitrogen were noticeable i n this experiment. The content of nitrogen i n June, I960, was about 50 per cent lower i n a l l sites than i n the field samples i n 1959.  The blocks increased  nitrogen content during I960 at the surface i n a l l sites and i n the entire block profile of the Swordfern site (Table XXVI, Figure 28).  Unburned con-  t r o l variants showed higher increase i n nitrogen content than burned variants, especially on their surface layers. The above facts refer to an increased n i t r i f i c a t i o n which was here associated with mild greenhouse microclimatological conditions and regular adequate irrigation. The nitrogen transformation was not recorded i n this experiment, but the measurements of total nitrogen, the trend of i t s changes i n time, the increased s o i l pH, i t s ratio to the amount of organic matter, the symptoms of nitrogen deficiency on foliage, the dry matter production as  - 82 related to the aforementioned, and the changes i n vegetation offered some data comparative with the findings reported i n literature. Waksman (1936), using several references, stated that mild temperature up to about 32°C (90°F) promotes CCv, production i n the s o i l atmosphere by raising bacterial l i f e .  Waksman presents a table (p. 39) i n which he  shows increased nitrogen liberation i n a two-month-long incubation i n different humus types.  Moss material i s especially resistant to decomposition i n  nature."*" In this experiment the increase of s o i l pH over the c r i t i c a l value of 4 supports an indication of accelerated decomposition, caused by burning and the greenhouse effect. Increased n i t r i f i c a t i o n after forest fire was observed by a large number of workers.  Sushkina (1933) i n Russia, Fowells and Stephenson (1933)  and Tarrant (1956;,c) i n North America, Kivekas (1939) i n Finland, and Uggla (1957) i n Sweden, amongst many others, experimentally proved this fact. Hesselman (1916) observed i n Sweden an increased n i t r i f i c a t i o n , denitrification and nitrate reduction after forest f i r e s .  Svenhufruid (1929) proved that 25  per cent of NH^ produced i n burning of peat can be absorbed by the s o i l . Barnette and Hester (1930) found generally an increase of nitrogen.  On the  other hand, they estimated for i t an annual loss of about 27 l b . per acre, in New Jersey.  Heyward and Barnette (1934) discovered a 14 per cent increase  of nitrogen to a depth of four and six inches.  Lutz (1934) reported a slight  loss i n New Jersey; Osborn (1931) reported loss of nitrogen i n Africa i n the clayey and loamy upper two-inch layer; but Greene (1935) found one and a half ^Nemec, A.  1951. Personal communication i n Prague.  - 83  times more nitrogen i n the upper six-inch layer after fire i n the Mississippi longleaf pine Region.  Finn (1934) performed an experiment i n boxes, i n which  the covering organic material was burned. after the burn.  He found a reduction of nitrogen  Hesselman (1937) observed a release of volatile nitrogen.  Kivekas (1939) found an increase of amino-acid nitrogen to protein and amide nitrogen.  The total nitrogen proved to be reduced, but not to a c r i t i c a l  level to plants.  Isaac and Hopkins (1937) could not find any significant  change i n nitrogen in the Douglas-fir Region, nor did Chapman (1942) i n the West Mississippi Region. Lutz and Chandler (1946)> dealing with the problem of available nitrogen, pointed out that the immediate loss of nitrogen after fire does not mean;necessarily a decrease i n available nitrogen.  (They recorded an  original average of 0.1 to .15 per cent of nitrogen in the six-inch surface layer of a brown s o i l and 0.05 to 0.20 per cent i n gray-brown podzolic s o i l ) . Garren (1943) observed increase of nitrogen after fires on Southeast, as did Lunt (1951) i n the Northeast White Pine Zone.  Rideout (1949) detected an  increase i n ammonia and a loss of nitrates by leaching associated with severe burning. Austin and Baisinger (1955) observed 67 per cent loss of nitrogen i n the 12-inch top-soil layer, 75 per cent of which was recovered in two years. heavy humus.  Tamm (1950) stated that fire stimulates nitrification on Duchaufour (1954) suggested to burn the superficial humus layers  and sow immediately to reap the benefit of increased s o i l activity and to prevent leaching.  Metz et a l . (1961) experimentally proved that organic  matter i n the mineral s o i l w i l l increase after the f i r e .  They observed i n  North Carolina an increase with nitrogen, phosphorus, potassium, calcium, magnesium and s o i l pH i n the surface four inches.  Wright and Tarrant (1957)  - 84 observed increased microbiological activity i n the severely burned s o i l with a large population of bacteria and actinomycetes. Charcoal, Eluviated Layer and Concretions The charcoal remains, the Ae layer, and concretionary formations did not form sufficient continuous layers i n the blocks for chemical analysis. Field samples were collected i n 1959 and were analyzed i n 1961 (Table XXVII). 1. Charcoal remains from the forest fire had chemical properties similar to the overlying surface layer, with pH and cation exchange capacity; but their saturation of Ca, Mg and K ions was higher i n the Swordfern site (33.4) and much lower i n the Salal site than that of the overlying layer. In the Swordfern site saturation of charcoal was about 50 per cent higher than that of the surface layer.  Nitrogen content i n the organic matter was  strikingly smaller i n charcoal than i n the Ah layer, especially i n the Swordfern type, with a ratio of 53 to 551. Content of phosphorus i s about 70 p.p.m. i n the upper layer i n the Moss and Salal sites; charcoal i n both these sites contained 49 p.p.m.  In the Swordfern site charcoal had 32 p.p.m.,  whereas the surface layer had no detectable free phosphorus content. Of the earliest workers on this problem, Hesselman (1916), Fritz  (1930), and KivekSs (1939) believed that charcoal i n the s o i l favoured bacterial l i f e .  Salisbury (1925) observed that charcoal increased nitrate and  carbonate content of the s o i l and reduced acidity.  Tryon (1948) studied the  effect of charcoal i n forest soils and reported a change i n moisture balance, increase i n nitrogen content and a decrease i n the base exchange capacity with coniferous charcoal.  He did not accept, however, the beneficial effect  of charcoal on bacterial l i f e .  Swenson (1939) and Tryon (1948) also a t t r i -  buted a significant role to charcoal i n the moisture balance of the upper s o i l .  - 85  Davis (1959) also believed i n the beneficial presence of charcoal after f i r e . Beaton (l959„-b) found that charcoal may absorb phosphate ions. Charcoal i s probably a useful nutritional source i n the Swordfern site.  On the Moss and Salal sites, however, where base saturation of char-  coal i s as low as 5 and 6 per cent for the three cations, i t has less nutritional value. 2.  The eluviated Ae layer had lower pH values than the surface layer  and the charcoal i n the Swordfern and Salal sites.  The Moss site, however,  showed an eluviated material with higher pH than both overlying layers.  The  sequence of the pH value was as follows i n a nearly uniformly decreasing order:  Swordfern - Moss - Salal, which i s consistent with the similar  sequence of pH for the entire used s o i l profile. Cation exchange capacity of the eluviated material is always only a fraction of that of the overlying layers. per cent, was shown i n the Swordfern site.  The smallest decrease, about 10o The studied three mineral cations  were present i n a greatly decreased proportion i n the eluviated layer forming low saturation i n the Swordfern and Salal sites, but increased i n the Moss site, where the cation exchange capacity was extremely low.  The content of  nitrogen i n the eluviated material i s far below that of the surface layer. Phosphorus dropped below the values of the upper layers with the Salal and Moss sites and was strikingly low i n the Moss site, 20 p.p.m. 3.  Concretionary material from the Swordfern B layer showed chemical  properties very similar to the proper B layer, being slightly lower i n saturation of the three cations and i n phosphorus content.  to follow page 85  UJ  CL +3  LO  Z <  LU U CC LU  a.  T B S 0  N P  ION EXGH. CAPACITY CATIONS OF Ca.Mg.K SATURATION OF SAME ORGANIC MATTER NITROGEN ' PHOSPHORUS  FIGURE 28.1a. SWORDFERN CHANGES OF ;  MATTER  DRY WEIGHT OF TWELVE SEEDLINGS 1960 1961  B 0  N  PW  1 9 59  SITE - AVERAGE,ENTIRE BLOCK SOME CHEMICAL PROPERTIES IN.THE SOIL SAMPLES AND DRY  PRODUCTION OF THE CORRESPONDING SEEDLING BLOCKS.  to follow page 85  FIGURE 28.1b . SWORDFERN CHANGES OF MATTER  SITE - AVERAGE FOR ONE INCH SURFACE LAYER SOME CHEMICAL PROPERTIES IN THE SOIL SAMPLES AND DRY  PRODUCTION OF THE CORRESPONDING SEEDLING BLOCKS  to follow page 85  FIGURE 28.2a. M O S S SITE - AVERAGE FOR ENTIRE BLOCK CHANGES OF SOME MATTER  CHEMICAL PROPERTIES IN THE SOIL SAMPLES AND DRY  PRODUCTION OF THE-COR RESPONDING SEEDLING BLOCKS.  to f o l l o w  page  85  o o  UJ —'  f y -  U °  c_> cr UJ  CATION EXCH.CAPACITY CATIONS OF Ca.Mg.K SATURATION OF SAME ORGANIC MATTER NITROGEN PHOSPHORUS  W- DRY WEIGHT OF TWELVE SEEDLINGS  B  1960  0  1961  N  PW  1 9 59  FIGURE 28.2b. MOSS SITE - AVERAGE FOR ONE INCH SURFACE LAYER CHANGES OF SOME CHEMICAL PROPERTIES IN THE SOIL SAMPLES AND DRY MATTER PRODUCTION OF THE CORRESPONDING SEEDLING BLOCKS.  qo  to follow page 85  FIGURE 28.3a.  SALAL SITE - AVERAGE FOR EN TfRE BLOCK CHANGES OF SOME CHEMICAL PROPERTIES IN THE SOIL SAMPLES DRY MATTER PRODUCTION OF THE CORRESPONDING SEEDLING BLOCKS  AND  to follow page 85  cc  UJ  co n  a. z UJ  ^  _J °  52  UJ  o cr  UJ  a.  T - CATION EXCH. CAPACITY B - CATIONS OF Ca.Mg.K S - SATURATION OF SAME 0 - ORGANIC MATTER N - NITROGEN P - PHOSPHORUS  W - DRY WEIGHT OF TWELVE SEEDLINGS  1 1  B 0  1960 1961  N  i 959  FIGURE 28.3b. SALAL SITE - AVERAGE FOR ONE INCH SURFACE LAYER CHANGES OF SOME CHEMICAL  PROPERTIES IN THE SOIL SAMPLES  DRY MATTER PRODUCTION OF THE CORRESPONDING SEEDLING  AND  BLOCKS  - 86  Effect of Chemical S o i l Properties on Dry Matter Production Table XXVI presents the chemical properties of s o i l sample blocks for the surface layer and the average for the whole profile in three subsequent years.  In Tables XXVIII, XXIX and XXX deviations between the unburned  control blocks and their burned variants are shown for each year, and the changes are computed for each treatment from I960 to 1961. The deviations by treatment and the changes by time are expressed i n percentage. Table XXXI shows those selected data from the above-mentioned tables which are directly correlated to the productivity of the corresponding seedling blocks.  The selected highest concentration of a nutrient and/or i t s  increase was associated with highest productivity, and the lowest concentration and/or i t s decrease was correlated to the lowest productivity. The following chemical s o i l properties and their changes showed direct correlation to the productivity of the variant. 1.  In the Swordfern site the highest production of the severely burned  variants was associated with a high value of s o i l pH in 1961 for the block average, the highest base saturation of the three cations i n the block for I960 and i n the surface layer for 1961, and the highest concentration of phosphorus generally.  The lowest organic matter per nitrogen ratio was  generally characteristic  (^).  The unburned control variants had the lowest production i n the Swordfern site.  This treatment resulted i n the lowest pH for the block i n  1961, a low base saturation for the block in I960, and the lowest concentration of phosphorus for the block in 1961, indicating the absence of lateral leaching.  Organic matter per nitrogen ratio for the block was high i n 1961.  - 87 Productivity of the moderately burned variants of the Swordfern site was close to that of the severely burned variants.  Results are consistent with  the generally highest pH values, high base saturation for the block i n 1961, and high phosphorus concentration for the block i n I960. The deviation of values of burned variants from values of the unburned control variants also shows some parallels.  In the most productive  severely burned variant, base saturation had the greatest increase in time for the surface layer and greatest deviation from the unburned specimen for the block in I960 and for the surface i n 1961. The decrease i n organic matter per nitrogen ratio was general.  The increase of deviation from unburned type for  phosphorus was generally highest. The lowest production on unburned variants was indicated by an extreme decrease of base saturation by time and increase of organic matter per nitrogen ratio for the block.  In the Swordfern site nitrogen obviously had a  limiting role i n plant production during the experiment. On the severely bumed Swordfern blocks was produced the highest crop for a l l species.  Similar acceleration of plant growth by heat effect  was reported by many authors:  Pickering, 1910; Seaver and Clark, 1912;  Wilson, 19H; Hensel, 1923; Shirley, 1932; Greene, 1935; Tarrant and Wright, 1955; and Lutz, 1956. This experiment corroborated the findings, reported by Tamm (1950), that burning benefits mineral soils with higher concentration of nutrients better than poor soils.  Here the s o i l of the Swordfern site was more  benefited by severe burning than that of the Moss or Salal s i t e . 2. In the Moss site, unburned variants showed the highest productivity. The highest pH for the block i n I960, the highest base saturation for the  -88 block i n I960 and for the surface i n 1961, and the lowest organic matter per nitrogen ratio for the surface i n I960 are probably responsible.  The severe-  l y burned variant, on the contrary, had the lowest base saturation for the block, generally the highest organic matter per nitrogen ratio, and the lowest phosphorus concentration for the block i n 1961. The deviations of values showed consistency with the production for severely burned variants, where the pH, organic matter per nitrogen ratio and phosphorus declined i n I960, and where the base saturation for 1961 showed the largest decrease along with a decrease of phosphorus i n the block average. The increase of chemical values by time was highest for the unburned variant with base saturation and phosphorus generally.  The severely burned  variant showed the greatest decrease i n both base saturation and phosphorus concentration i n I960 for the surface layer. The moderately burned variant, which had mediocre productivity on the corresponding blocks, produced by burning marked positive deviations i n phosphorus content and nitrogen ratio, and their s o i l pH i n I960 dropped for the block average. On the Moss site, base saturation of the three cations appeared to be the major 1i mi ting factor, especially at the beginning of plant growth i n I960.  3.  On the Salal site blocks, moderately burned variants had the highest  productivity and the severely burned blocks had the lowest.  Table XXXI - C  shows the most favourable conditions on the moderately burned variant, for a l l three groups of data, except nitrogen which was not decisive i n this entirely organic type of s o i l .  - 89 The s e v e r e l y burned v a r i a n t , c o r r e s p o n d i n g  t o the l o w e s t produc-  t i v i t y , had the l o w e s t i n i t i a l pH and low base s a t u r a t i o n f o r the b l o c k i n 1961.  The n i t r o g e n r a t i o was  from 1960  unfavourable  t o 1961 were a l s o most u n f a v o u r a b l e  o r g a n i c m a t t e r per n i t r o g e n r a t i o . for  i n the s u r f a c e i n 1961.  the b l o c k average i n  Changes  f o r b o t h base s a t u r a t i o n and  B u r n i n g somewhat r a i s e d base s a t u r a t i o n  1961,  The unburned v a r i a n t improved i t s s a t u r a t i o n and n i t r o g e n r e l a t i o n ships w i t h time.  F o r t h i s reason s e v e r e l y burned and unburned v a r i a n t s  changed t h e i r p l a c e s i n second y e a r In  ( F i g u r e 25-3).  the S a l a l s i t e , base s a t u r a t i o n o f the t h r e e d e t e c t e d c a t i o n s  and the d e c r e a s e o f a c i d i t y were r e s p o n s i b l e f o r the h i g h p r o d u c t i o n . moderate b u r n i n g r a t e o f t h i s experiment was  The  s u i t a b l e t o produce the most  f a v o u r a b l e changes because i t r e d u c e d the e x c e s s i v e a c c u m u l a t i o n s  of organic  m a t t e r w i t h o u t the extremes o f the s e v e r e b u r n i n g r a t e . D i s c u s s i o n of F i n a l R e s u l t s . D u r i n g the whole experiment i t became e v i d e n t t h a t a l l t h r e e m o d i f i e d s i t e s responded t o f i r e i n d i f f e r e n t ways. the  I t remains t o d i s c u s s  reasons. The S w o r d f e r n s i t e , d e p r i v e d of i t s seepage w a t e r , by w h i c h i t  becomes the most p r o d u c t i v e s i t e o f the C o a s t a l w e s t e r n hemlock zone, b e n e f i t e d by b u r n i n g w h i c h induces r a p i d m i n e r a l i z a t i o n s u p p l y i n g e l e m e n t s , n o r m a l l y brought h e r e by seepage w a t e r .  Nitrogen f i x i n g organisms, present  i n t h i s s i t e ( K r a j i n a , personal communication), r e a d i l y supply n i t r o g e n compounds burned out by f i r e . corresponded  The  decreased  c a t i o n exchange c a p a c i t y  t o an i n c r e a s e o f c a t i o n s a t u r a t i o n s t r o n g l y r e l a t e d t o  - 89a p l a n t growth.  T h e r e f o r e , t h e unburned c o n t r o l b l o c k s d e v e l o p e d the  s h o r t e s t p l a n t s , whereas  the burned b l o c k s produced t a l l e r p l a n t s .  Thus,  f i r e causes the l e a s t damage t o t h i s m o d i f i e d s i t e , and i t became even b e n e f i c i a l , a t l e a s t f o r t h e f i r s t two y e a r s . still  However, i t s h o u l d be  t e s t e d i n s i t e s where seepage w a t e r remains i n a c t i o n . The Moss s i t e , w h i c h i s w i t h o u t seepage w a t e r a l s o i n n a t u r e ,  b e n e f i t e d i n the greenhouse by r a p i d d e c o m p o s i t i o n o f raw humus.  This  f a s t d e c o m p o s i t i o n a c t e d b e s t i n unburned c o n t r o l b l o c k s where the humus i s r e l a t i v e l y t h i c k and u n d e r l a i n by deep g l a c i a l d r i f t s o i l , istic  for this s i t e .  character-  T h i s f u l l a c t i o n of r a p i d d e c o m p o s i t i o n under t h e  greenhouse environment w h i c h s u p p l i e d r e q u i r e d n i t r o g e n compounds and o t h e r n u t r i e n t s was impeded by b u r n i n g w h i c h d e c r e a s e d the t h i c k n e s s o f the humus.  I n m o d e r a t e l y and e s p e c i a l l y s e v e r e l y burned b l o c k s s h o r t a g e  o f n i t r o g e n s u p p l y causes t h e p l a n t s t o grow l e s s . s e r i o u s damage t o t h i s  Thus f i r e causes  site.  The S a l a l s i t e , c h a r a c t e r i z e d by a t h i c k raw humus h o r i z o n d e v e l o p e d on s h a l l o w o u t c r o p s o i l s , b e n e f i t s from a moderate b u r n a t l e a s t f o r the f i r s t two y e a r s a f t e r the b u r n .  T h i s p a r t i a l b u r n i n g o f raw  humus r e l e a s e s m i n e r a l s t h a t a c t as a f e r t i l i z e r and e n r i c h the n u t r i e n t s u p p l y from t h e remainder o f the humus l a y e r .  When a l l t h e humus i s  burned, t h e r e i s l e f t v e r y l i t t l e n i t r o g e n and o t h e r n u t r i e n t s u p p l y ; thus t r e e growth i s g r e a t l y impeded.  I n unburned c o n t r o l b l o c k s growth  p o t e n t i a l s r e m a i n t h e b e s t , a l t h o u g h they cannot be demonstrated i n the two y e a r e x p e r i m e n t .  I n the S a l a l s i t e moderate b u r n i n g i s b e n e f i c i a l  f o r a two y e a r growth, whereas s e v e r e b u r n i n g i s most d e s t r u c t i v e f o r t h e habitat.  - 90 CHAPTER FOUR - SUMMARY AND CONCLUSIONS This thesis describes an experiment i n which, after a controlled burning of original s o i l blocks, seedling growth was correlated to the burning  and to the chemical changes i n corresponding s o i l sample blocks. The surface of 84 s o i l blocks, collected from three different sites  of the Coastal Western Hemlock Zone, was burned at two intensities i n the laboratory i n March, I960. and Salal s i t e .  The three sites were:  Swordfern site, Moss site  Forty-two unburned control blocks were also added for com-  parison. Four replicas of each combination of three sites and three treatments were seeded i n A p r i l , I960, with Douglas-fir, western hemlock, or western redcedar.  The blocks supporting seedlings and those reserved for  s o i l analysis were regularly irrigated with d i s t i l l e d water.  Seedlings from  50 seed on each seedling block were gradually thinned to three plants. Breaking of dormancy hastened growth i n the winter of 1960-61. The germination, growth and the changes i n accompanied vegetation were periodically recorded. 1961,  At the conclusion of the experiment i n June,  final size and the dry weight of seedlings were studied on each block  to determine treatment differences.  Relationships to s o i l chemism were de-  termined from s o i l samples taken i n 1959 from the area of block collection, and i n June of i960 and 196l from unseeded s o i l sample blocks. Effect of Burning 1.  To imitate slash burning a heat of about 1800°F for 35 minutes was  accepted for severe burn and about 1250°F for 15 minutes for moderate burn. These rates were applied at the surface of s o i l blocks irrigated with an  equivalent of one inch of precipitation before burning. It was observed that different rates of burning could produce similar heat effects on different soils.  The severity of burning could not  always be related to the destruction of organic remnants.  Soils with a thin  organic layer, or without such layer, can lose a l l organic material from the surface at the slightest burn.  On the contrary, on soils with heavy organic  accumulation the most severe burn w i l l not destroy a l l raw humus. Burning can be distinguished into light, moderate and severe i n two ways.  A useful indicator for the grade of burning for humus-less soils is  the change of the mineral s o i l surface.  The degree of destruction on the  other hand i s a good indicator for soils with heavy organic accumulation. The only safe determinant of any burning process, however, i s the temperature and the duration. 2.  The use of a natural-gas burner and recording by means of thermo-  couple elements at three different levels i n the burned blocks were satisfactory methods for the controlled repetitions of two burning rates. 3.  The recorded temperatures indicated that the mineral s o i l was  more severely affected i n the bare Swordfern site than i n the ether two "organic soils".  Two to three inches of the Swordfern site were strongly  affected by severe burning (500 to 700°F).  On the Moss site only the upper  one-inch mineral layer was affected by severe burning.  In the Salal site,  mineral s o i l was never reached by an excessive higher temperature. 4.  The experiment showed that an insulating sweating zone was formed  i n the heated s o i l .  Evidence was found that the loss of latent heat i n the  s o i l moisture during vaporization decreased s o i l temperature below the sweating zone by as much as 5°F during the f i r s t five to ten minutes of  - 92 burning, i n 29 per cent of a l l cases.  It was also observed i n the shallow  Salal blocks that the thermo-dynamic effect of vaporization exerted a downward force on the water. 5.  In addition to the ash and charcoal, a third product, coke, was also  produced on the organic surface. On the mineral s o i l surface, aggregates which never covered more than 20 per cent of the block surface were formed, but they never formed a harmful coherent layer. When the productivity of sample blocks was plotted against the corresponding burning rates, destruction and remains, a uniform consistency was found within each site for a l l three species.  Severe burn produced  slightly more ash and moderate burn produced somewhat more charcoal i n comparison with each other. Changes i n Accompanied Vegetation 1.  Algae appeared on 59 per cent of Salal blocks and 7 per cent of  Swordfern and Moss blocks in May, regardless of the treatment. 2.  Fungi occupied only burned blocks i n the f i r s t year and i n the  second year invaded the unburned blocks to a lesser extent.  In February,  1961, 4 6 per cent of burned blocks and 9 per cent of unburned blocks s t i l l supported fungi. Eumycetes were established, however, i n December, I960, i n larger proportion on unburned blocks (28 per cent) than on burned blocks ( l l per cent). In the f i r s t year a l l three sites were equally infested with fungal flora.  In December, the Swordfern site had the highest and Salal site the  lowest number of fungi on burned blocks.  In February, 1961, the sequence  - 93 was reverse. 3.  The burned surfaces were sooner invaded by new mosses than those  supporting old dying mosses.  There was no noticeable difference  otherwise,  in the invasion of unburned or burned surfaces. 4.  Pteridium aquilinum survived severe burning and flushed from a deep  rhizome. 5.  Burned blocks were mostly invaded by dicotyledons among the woody  plants, such as Alnus rubra, Populus trichocarpa, and Salix scouleriana. Establishment of Seedlings 1.  A germination test on moist pure ash from slash produced evidence  that the germination capacity of Douglas-fir was increased by +2.6 per cent, hemlock was reduced by -48.6 per cent and redcedar by -82.2 per cent. Probably the chemical effect of concentrated ash lye on the seed coat was responsible for the result. 2.  No consistent difference i n germination was observed on blocks as  a result of burning, and no general correlation of germination was found with results to the f i n a l production.  Only the severely burned Swordfern site  blocks already showed their final superiority with both Douglas-fir and redcedar i n both germination and survival. Severe and moderate burning generally resulted i n somewhat better results in germination with Douglas-fir and hemlock than the unburned variants.  Redcedar had somewhat lower results on burned surface. The evenness of the seedbed and the adequate position of seed i n a  moist medium seemed to be more important than the material of the ground. 3.  In size, colour and vigour of germinants, no difference was  observable during the f i r s t month.  - 94 No effect of the reported s o i l sterilization by heat was obvious on  4.  burned blocks versus unburned control.  On the contrary, Douglas-fir germin-  ants on May 5 had much higher proportion of defective specimens by infection on burned variants than on unburned blocks. off occurred on the burned blocks.  Less than one per cent damping-  Hemlock and redcedar germinants were a l l  sound. In one-month-old plants 20 to 29 per cent of each species were defective regardless of the treatment.  The presence of fungi on burned blocks  showed an early infection. Root penetration of one-month-old Douglas-fir seedlings was deeper  5.  in unburned blocks than on burned ones, with both sites - Swordfern and Moss. Hemlock and redcedar, on the contrary, penetrated deeper i n burned blocks than i n unburned control variants, for both mentioned sites. The establishment of seedlings after one month of growth, i n terms  6.  of per cent of plants to the standard germination, showed highest average (54) with severely burned blocks.  The moderately burned and the control  variants averaged nearly an equal value (46.5 and 45.5).  The individual  values, however, were inconsistently spread over a wide range. Seedling Growth The three sites employed i n this experiment produced three different  1.  rates of growth, which were consistent for each site with a l l three species for both seedling size and dry plant production. The growth i n size and weight at the end of a two-year growing period was as follows (Figures 19 to 23, and Table XXXII): a.  Swordfern site had highest production on severely burned blocks,  - 95  close to this on moderately burned and highly significantly lowest on unburned control sample blocks i n both size and weight. b.  Moss site had highly significantly higher production i n both size  and weight on unburned control blocks than.on burned blocks with Douglas-fir, and the same relation by weight on a significant level with western hemlock. Western redcedar followed the same sequence with treatment, though without significant differences by weight. c.  ,  Salal site produced highest crop on moderately burned sample blocks,  mediocre on unburned control and lowest on severely burned blocks.  The dif-  ference in size and weight between the moderately burned and severely burned variants was significant for Douglas-fir and hemlock, and highly significant for redcedar.  The unburned variant was not significantly different from the  other two treatments by weight. The poor height growth of hemlock on unburned blocks i n the f i r s t year growth was due to i t s particular habit for developing branches rather than height growth i n the f i r s t year.  Plotting the number and rank of  branches, the sequence of variants shows identical trend as that of the height variants with the other two species. In this experiment the heat effect of severe burning was beneficial on the almost bare Swordfern site and harmful on the other two sites with organic accumulation.  Moderate burning gave the highest results on the  Salal site where i t only reduced and activated the thick raw humus. The experiment gave evidence to the findings of many authors that high temperature improves the nutritional capacity of mineral s o i l . This experiment produced evidence to support the belief that burn i s more harmful on poor soils than on rich s o i l (Tamm,  1950).  Here the  - 96 Swordfern site s o i l was improved by burning and the Moss site was deteriorated. The experiment corroborated the statement that severe fire is extremely harmful for purely organic s o i l . 2.  The differences i n the rate of growth i n relation to the treatment  were also obvious i n the case of Douglas-fir by a different number of phases of growth.  Douglas-fir showed five distinct growing phases on a l l blocks of  the burned Swordfern site, on unburned Moss blocks and on the moderately burned Salal site. fern site.  It showed only three phases on the unburned control Sword-  In a l l other cases four phases were observed.  consequent with the final grade of production.  The correlation is  The development of Lammas  growth had a slight correlation with the treatment on Douglas-fir where the unburned variants produced a higher proportion of such formations than the burned samples, regardless of the quality of growth. Hemlock and redcedar grew uniformly i n three growing phases.  1  Hem-  lock produced the least Lammas growth (5 per cent), whereas redcedar showed Lammas growth mostly on the best growing seedlings regardless of treatment. Bud dormancy and i t s response to breaking were correlated to the species but not to the treatment. 3. basis.  The shoot/root ratio (S/R) showed some consistency on a weight That ratio was higher on unburned variants than on burned blocks,  regardless of the growth. 4.  Water content of the harvested seedlings was somewhat higher i n  seedlings from severely burned blocks than i n the other two variants. 5.  A remarkable qualitative feature was shown i n the discoloration  of seedlings during the experiment.  The changes i n colour were l i k e l y  caused by nutritional deficiency and were inconsistent with the size of  - 97 seedlings. The f i r s t chlorotic Douglas-fir seedlings were observed i n July, I960, on some of the unburned Swordfern site and severely burned Salal site blocks.  There were, however, a few pale seedlings found among the best pro-  ducing severely burned Swordfern site and moderately burned Salal site blocks as well. Hemlock had at the same time a high proportion of chlorotic seedlings on a l l unburned blocks, especially on the Swordfern site. Redcedar had much purplish discoloration on a l l severely burned Swordfern site and Moss site blocks, but none or very l i t t l e on the unburned controls.  The Salal site supported a small number of seedlings with discol-  oration, a l l of which were on unburned variants.  At the early stage of the  experiment, nitrogen deficiency was probably the reason for discoloration. During the winter dormancy a general purple tint of a l l redcedar seedlings was conspicuous, when n i t r i f i c a t i o n l i k e l y slewed down. At the commencement of the second-year growth, after the breaking the dormancy, single cases of deficiency were shown on Douglas-fir seedlings, mostly on unburned Swordfern and severely burned Moss site blocks.  Hemlock  seedlings were generally pale on burned Moss and Salal site blocks. The "Magnesium bar" emerged only i n one case with hemlock on unburned Salal site i n February, 1961. Douglas-fir and redcedar were mostly affected by discoloration of their old leaves, which refers to a deficiency in mobile nutrients such as nitrogen, potassium, phosphorus and magnesium.  Hemlock often had discolora-  tion also on young organs referring to deficiency i n mobile nutrients such as calcium.  - 98 Chemical Soil Properties and Productivity The changes of chemical s o i l properties after burning were immediate  1.  changes and continuous chain reactions, which were detectable u n t i l the end of the experiment. The effect of heat acted i n two ways:  f i r s t , i t destroyed organic  material, initiated physico-chemical processes i n the raw humus and left ashes behind; secondly, i t changed the mineral s o i l both physically and chemically, and introduced profound pedogenic processes.  The amount of ash  was low i n this experiment because of the lack of slash material. 2.  The experiment suggested that the main beneficial effect i s not the  ash production but the chemical and biological changes which are initiated by the heat i n the mineral and organic s o i l . The destruction of organic accumulation appeared to be harmful; but i f i t removed only part of the accumulation, then rather beneficial.  The  effect of heat on mineral s o i l had generally beneficial effects for s o i l chemism probably by the improved solubility of salts and by accelerated nitrification.  The direct effect of heat did not influence layers below  about 4 inches i n the severe burn and below about 2 inches i n the moderate burn. The combination of the effect of burning upon organic accumulation  3.  and on the mineral s o i l resulted i n the following chemical changes in the three sites. a.  The Swordfern site suffered l i t t l e by the destruction of i t s i n -  significant unincorporated organic material, but i t s mineral s o i l was strongly affected by heat.  This site was the richest i n nutritional value,  although by removal i t was depauperated by the loss of lateral seepage.  The fire here acted beneficially, increasing s o i l chemical properties related to productivity such as pH, base content, saturation, phosphorus and nitrogen content. b.  The Moss site lost i n severe burning a l l of i t s accumulated nutri-  ents by the destruction of raw humus, mainly nitrogen without beneficial effect of heat upon i t s poor mineral s o i l .  sufficient  On the unburned  samples an accelerated pedogenic process was induced by consistently mild conditions i n the greenhouse.  As a result, the nutritional capacity of un-  burned control samples, expressed mainly by base saturation, surpassed the capacity of burned blocks. c.  On the Salal site, burning destroyed part of the raw humus.  In the  extreme case of the Salal site, very l i t t l e or none of the mineral s o i l was present.  Severe burning destroyed too much of the humus, the only substance  supporting plants.  Moderate burn left a sufficient proportion of the raw  humus for available nutrients, raised base saturation and introduced accelerated pedogenic processes i n the remaining parts. be the most successful.  This variant proved to  The excessive raw humus of the unburned control  blocks could not yet enter into a proper process of n i t r i f i c a t i o n and decomposition. 4.  There was no remarkable deficiency i n the organic matter and in  nitrogen, except on the unburned Swordfern site blocks.  The destruction by  burning was soon more than offset by an increased n i t r i f i c a t i o n . Temporary deficiencies with hemlock and redcedar were recovered i n the second year. 5.  The experiment corroborated the positive effect of burning on  s o i l pH. 6.  The major factor i n chemical changes was shown i n the decrease of  - 100 cation exchange capacity which was inversely correlated with the productivity for each site.  It was not associated with the intensity of burn but rather  to the initiated increased pH and decomposition, 7.  The concentration of the three studied metallic cations (CaMgK) was  not related to the nutritional value of s o i l .  It became determinative i n  combination with the cation exchange capacity, which controlled base saturation, probably the major factor of plant production. 8.  The degree of saturation of the three mineral cations increased  with severely burned Swordfern and unburned Moss blocks which had the highest production.  The same saturation showed the lowest values on the worst un-  burned Swordfern, and severely burned Moss and Salal blocks.  This correla-  tion supports findings concerning the limiting capacity of the degree of base saturation. 9.  Phosphorus concentration was increased by burning on the Swordfern  (167 per cent) and Salal sites.  On the Moss site the severely burned, less  productive variant had the lowest value (3 p.p.m.). 10.  The charcoal samples from field collection showed that i t s chemical  properties are related to the overlying organic layer.  The presence of char-  coal seems to be useful not only for i t s high water-holding capacity but also for i t s nutritional value, especially for the most dry Swordfern site. Additional Observations In the experiment some results, which were not directly related to the subject matter, were used for basic information or comparison. 1.  The three sites used i n the experiment proved to be different i n  many respects and reacted differently to the uniform treatments.  This fact  corroborates the necessity of site classification accepted i n other studies of the Department of Biology and Botany of U. B. C . , and points to a demand of different silvicultural treatments by forest management.  The importance  of lateral seepage i n the Swordfern site and the chief nutritional supply i n the raw humus on the Moss site were evident i n this experiment. 2.  Strong effects of greenhouse conditions combined with changes  caused by the removal of s o i l blocks from the natural environment resulted i n the formation of new a r t i f i c i a l sites, regardless of subsequent treatments.  The Swordfern site was depauperated of i t s main source of nutrition,  the lateral seepage:  the Moss and Salal sites were, on the contrary, sup-  ported by an accelerated decomposition of their inactive organic remains. Soil pH was increased by the greenhouse effect by a value of 0.7. 3.  S o i l pH was consistently raised by the chelating effect of seed-  ling roots.  Douglas-fir had the most prominent effect with an average of  0,6 pH value of increase, and both hemlock and redcedar by 0.15. The rhizosphere effect was highest for a l l species on the Moss site,  especially  for Douglas-fir with a value of increase of 0,94 pH. 4.  Earthworms were found i n the Salal site i n mineral s o i l on the  surface of the bedrock, at a low s o i l pH of 4.10 to 4.25. 5.  Seed stratification for 93 days increased Douglas-fir germination  from 36 per cent to 90 per cent.  Western hemlock had an i n i t i a l germina-  tive capacity of 75 per cent, which decreased by stratification to 68 per cent.  Without stratification hemlock decreased germinative capacity to  54 per cent.  A few stratified hemlock seeds germinated subsequently for  five months i n some seedling blocks.  The unstratified western redcedar had  a germinative capacity of 78 per cent which dropped, i f not stratified, to  74 per cent and i f stratified, to 28 per cent. 6.  A direct correlation was shown between the different features of  growth, such as height, diameter, needle length, bud size, branching, and the dry matter weight of seedlings.  The height, therefore, was a f a i r l y reliable  characteristic for growth, especially with Douglas-fir and western redcedar. The height of western hemlock seedlings i n the f i r s t year was not as much correlated with their general development as with their branching habit.  The  best hemlock seedlings produced more branches and foliage than t a l l leaders. The formation of Lammas growth was not related to the general rate of seedling development. ing seedlings.  Only redcedar formed more Lammas growth on the best grow-  Thirty-one per cent of Douglas-fir seedlings, five per cent  of hemlock and twenty-three per cent of redcedar produced Lammas growth. Irregular, often spiral or curved stems of Douglas-fir and hemlock seedlings were associated with the most rapidly growing over-nourished specimens. This experiment produced evidence of a successful method of break-  7.  ing dormancy by c h i l l i n g and a r t i f i c i a l light i n a range of 125 to 250 foot candles.  The three species revealed different photo-periodic responses.  Redcedar commenced growth i n the second week of the illumination, hemlock i n the fourth, and Douglas-fir i n the seventh.  The whole period of bursting  covered about seven weeks from February 10 to March 31. 8.  ,  The shoot/root ratio of Douglas-fir seedlings was generally smaller  than with the other two species.  Douglas-fir developed a proportionally  larger root system to i t s aerial organs than the other two species, and western hemlock the smallest. 9.  There was an indication that Douglas-fir had the lowest water  content  (185 per c e n t ) and redcedar  age, water c o n t e n t o f r o o t s was 10.  Only 1.1  the h i g h e s t (251 per c e n t ) .  Western hemlock showed on 4.4  cent o f germinants f o u r c o t y l e d o n s , i n s t e a d o f t h r e e .  f i r from t h i s r e g i o n was  11.  per  A l l 176 redcedar  ger-  The range of the l e n g t h s o f h y p o c o t y l o f Douglas-  h i g h e r than t h a t p r e s e n t e d  F r a n k l i n (1961) measured 15 t o 35 mm.; such d i f f e r e n c e was  organs.  germinants o f D o u g l a s - f i r had more  t h a n the u s u a l f i v e - t o - s e v e n c o t y l e d o n s .  minants had two c o t y l e d o n s .  On the a v e r -  t w i c e as h i g h as t h a t o f the a e r i a l  per cent o f a l l 1236  103  i n the  h e r e 25 t o 38 mm.  was  literature. recorded.  No  found w i t h the o t h e r two s p e c i e s .  In the f i r s t year redcedar  developed  needles w h i c h were u s u a l l y  r e p l a c e d by n e e d l e - s c a l e s i n the second y e a r , except on weak s e e d l i n g s where needles year.  remained.  Branches were a l r e a d y c o v e r e d w i t h s c a l e s i n the f i r s t  I f the l e a d e r t i p was  damaged, n e e d l e - c o v e r e d  branches were produced  from l a t e r a l dormant buds on the stem; t h e s e grew o n l y one Major 1.  year.  Conclusions  The S w o r d f e r n s i t e b e n e f i t e d from b u r n i n g by a c c e l e r a t e d m i n e r a l i -  z a t i o n , w h i c h s u b s t i t u t e d f o r the d e p r i v e d seepage.  F i r e caused the  least  damage t o t h i s h a b i t a t . 2.  The Moss s i t e s u f f e r e d h e a v i l y by b u r n i n g , w h i c h reduced humus,  the main s o u r c e o f n u t r i t i o n . decomposition 3.  The unburned b l o c k s were b e n e f i t e d by  fast  o f humus i n t h e greenhouse.  The S a l a l s i t e ' s t h i c k raw humus b e n e f i t e d from moderate b u r n ,  w h i c h removed p a r t o f the humus and a c t e d as a f e r t i l i z e r on the remainder. Severe b u r n i n g was  most h a r m f u l on t h i s s i t e by the d e s t r u c t i o n o f the  l a r g e p a r t o f humus. 4.  R i c h s o i l s , u s u a l l y w i t h seepage w a t e r , a r e l e s s damaged by  than poor s o i l s w i t h s t r o n g d r a i n a g e . organic matter  I t i s m a i n l y because i n r i c h  fire  soils  i s a t l e a s t p a r t l y i n c o r p o r a t e d i n t o the m i n e r a l h o r i z o n  acts r e a d i l y a f t e r f i r e e s p e c i a l l y f o r n i t r o g e n supply.  and  - 104 BIBLIOGRAPHY Ahlgren, C E . 1959* Some effects of f i r e on forest reproduction i n northeastern Minnesota. Jour. For. 57:194-200. Ahlgren, I.F. and C E . Ahlgren. I960. Ecological effects of forest fires. The Botanical Review, Vol. 26, No. 4:483-533. Allen, G.S. 1953. Slash burning i n the coastal Douglas-fir region of British Columbia. Proceedings of C.I.F. Monthly Meet., Nov., 1953. . 1954. Slash burning - Silvicultural aspects of the problem. B.C. Lumberman, March, 1954:76-84. . 1958. March, 1958.  Slash burning and silviculture. 6 pp.  C.I.F., Vane. Section,  , and W. Bientjes. 1954. Studies on coniferous tree seed at the University of British Columbia. For. Chron. 30:183-196. Alway, F.J. 1938. of jack pine.  Effect of burning the forest floor upon the production I Int. Cong. Soil Sci., Proc. 0 Pap.:5l4-524.  Anon. 1961. Definite progress recorded at Fourth National Forest Fire Research Conference. Woodlands Review, May, 1961:126-3, 154-30. Austin, R.C and D.H. Baisinger. 1955' Some effects of burning on forest soils of western Oregon and Washington. Jour. Forestry 53(4):275-280. Baker, F.S. 1950. Principles of silviculture. Inc., New York, Toronto, London. 4l4 pp.  McGraw-Hill Book Company,  Barnette, R.M. and J.B. Hester. 1930. Effect of burning upon the accumulation of organic matter i n forest s o i l s . Soil Sci. 29:281-284. Beadle, N.C.W. 1940. Temperature during forest fires and i t s effect on the survival of vegetation. Jour. Ecol. 28:180-192. Beaton, J.D. 1959* The influence of burning on the timber range area of Lac Le Jeune, British Columbia. II. Chemical properties. Canadian  Jour. Soil Sci. 39:1-11.  Bennett, W.D. i960. The reduction of the forest f i r e hazard created by logging slash. A literature review. Pulp and Paper Research Institute of Canada, Montreal. 56 pp. Bentley, J.R. and R.L. Fenner. 1958. Some temperatures during burning related to post-fire seedbeds on woodland range. Jour. Forestry  56:737-776.  Biswell, H.H. 1958. Prescribed burning i n Georgia and California compared. Jour. Range Manag., Vol. II, No. 6. School of Forestry, Univ. Calif., Berkeley, Cal. 292-298.  - 105 Burns, P.Y. 1952. Effect of f i r e on soils i n the pine barren region of New Jersey. Yale Univ., School of Forestry, Bull. 57, New Haven, Conn. 50 pp. Byram, G.M. 1958. Some basic thermal processes controlling the effects of f i r e on l i v i n g vegetation. Res. Note No. 114, U.S. Dep't. Agr., For. Serv. 1 p. Candy, R.H. 1951. Reproduction on cut-over and burned-over land i n Canada. Canada, Dep't. Res. 0 Devel., For. Res. Div., Silv. Res. Note 92. 224 pp. Chaiken, L.E. 19^9. The behavior and control of understory hardwoods i n loblolly' pine stands. U.S.F.S. Southeast For. Exp. Sta. Tech. Note 72. 27 pp. Chapman,.H.19^7. Prescribed burning versus public forest f i r e services. Jour. Forestry 45(11):8c4-808. Chrosciewich, Z. 1959« Controlled burning on jack pine sites. Canada, Dep't. North. Aff. # Nat. Res., For. Res. Div., Tech. Note No. 72. 19 pp. Crosbie, H.W. V$hO. Progress and problems of forestry i n the Trent District. For. Chron., Vol. XVI, No. 2:138-148. Daubenmire, R.F. 1936. The "big woods" of Minnesota: i t s structure i n relation to climate, f i r e and soils. Ecol. Monogr. 6:231-268. Davis, K.P. 1959* Forest f i r e ; control and use. Inc., New York, Toronto, London. 58^ pp.  McGraw-Hill Book Company,  Duchaufour, P. 195**-. The effect of burning on the development of humus. Revue forestiere francaise 6(5) Ol *—319* (From the For. Abstract 15). 2  KLpatievsky, M.P., S.P. Runiantsev, and B.K. Yarmelovich. 193^. Methods of slash disposal adapted to forest types. (From U.S. Forest Service Transl. 289). (Cited by Ahlgrens, i960). Finn, R.F. 193^. The leaching of some plant nutrients following burning of forest l i t t e r . Black Rock Forest Paper 1(2):128-13^. (Cited by  Ahlgrens, i960).  Forestry Faculty of U.B.C. 1959. The f i r s t decade of management and research of the U.B.C. Forest, 19^9-1958. U.B.C., Vancouver, B.C. 82 pp. Forest Club, U.B.C. 1959« Forestry handbook for British Columbia. Second edition. The Forest Club of U.B.C, Vancouver 8, B.C. Key to slash burning, p. 5^« Forest Soil Committee of the Douglas-fir region of the Pacific North West. 1957. An introduction to forest soils of the Douglas-fir region. Anderson Hall, Univ. Wash., Seattle. 217 pp.  -  106  Fowells, H.A. and R.S. Stephenson. 1933. Effect of burning on forest soils. Soil Sci. 38:175-181. (Cited by Isaac 0 Howard, 1937). Franklin, Jerry F. 1961. A guide to seedling identification for 25 conifers of the Pacific Northwest. Pac. N.W. Forest and Range Exp. Station. U.S.D.A. Forest Service, Sept. 1961. 65 pp. F r i t z , E. 1930. The role of f i r e i n the redwood region. Jour. Forestry 29:939-950. Garman, E.H. 1955. Regeneration problems and their silvicultural significance i n the coastal forests of British Columbia. Dep't. Lands and For., B.C. For. Serv. 67 pp. Gayle, W.B. and W.W. Gilgan. 1951. The effect of slash burning on germination and primary survival of lodgepole pine and Douglas-fir. U.B.C. For. Club, Res. Note No. 2, Vancouver, B.C. Gibson, J.M. 1958. I. The ages of Douglas-fir. II. The removal of the coastal forest. W.J. Vandusen Foundation — a fund of the Vancouver Foundation. 28 and 24 pp. Greene, S.W. 1935. Effect of annual grass fires on organic matter and other constituents of virgin longleaf pine soils. Jour. Agr. Res. 50:809-822. G r i f f i t h , B.G. i960. Growth of Douglas-fir at the University of British Columbia Research Forest as related to climate and s o i l . U.B.C, Vancouver, B.C. 58 pp. Hansen, H.P. 1942. Post glacial forests along the Alaska Highway i n British Columbia. Amer. Phil. Soc. 94(5):4l6-421. (Cited by Ahlgrens,  I960).  Hartman, A.W. 19^9* Fire as a tool i n southern pine. Agr., Agricultural Yearbook, 1949, pp 517-527.  Trees; U.S. Dep't.  Hawley, B.C. and D.M. Smith. 1954. The practice of silviculture. Sixth edition. John Wiley 0 Sons, Inc., New York. Chapman 0 Hall Ltd., London. 525 PP« Heikinheimo, 0. 1915. Der Einfluss der Brandwirtschaft auf die Walder Finnlands. Kaskiviljelyksen vaikutus suomen metsiin. Acta Forest. Fenn. 4:1-264. (Cited by Ahlgrens, I960). Hensel, R.L. 1923. Effect of burning on vegetation i n Kansas pastures. Jour. Agr. Res. 32:631-644. Hesselmann, H. 1916. Om vara skogsfBryngringsatgarders inverkan pa saltpeterbildningen i marken och dess detydelse fBr barrskogens fbryngring. (English summary i n Jour. Ecol. 7:213). Hesselmann, H. 1937. Uber die AbhSngigkeit der Humusdecke von aller und Zusammenselzung der Bestahde im Nordischen Fichtenwald von Blaubeereichem  - 107 Vaccinium-type und Uber die Einwirkung der Humusdecke auf die Verjttngung und Wachstum des Waldes. Medd. Statens SkogsfBrsoksant 30:529-716. (Cited by Ahlgrens, I960, and 0. Tamm, 1950). Heyward, F . 1937. The effect of frequent fires on profile development of longleaf pine forest s o i l s . Jour. Forestry 35*23-27. . 1938. Soil temperatures during forest fires i n the longleaf pine region. Jour. Forestry 36:478-4-91. , and R.M. Barnette. 1934. The effect of frequent fires on the chemical composition of forest soils in the longleaf pine region. Univ. Florida, Agr. Exp. Sta., Tech. B u l l . 265. Holbrook, S.H. 1943. Burning an empire. The story of american forest fires. (Foreword by Col. W.B. Greeley). The MacMillan Company, New York. 229 pp. Hosking, J . S . 1938. Ignition at low temperatures of organic matter i n s o i l s . Jour. Agr. S c i . 28: 393-400. Isaac, L . A . 1943. Reproductive habits of Douglas-fir. Pac. N.W.F.R.E.S., U.S. Dep't. Agr. Ch. Lathrop For. Found., Washington, D.C. Isaac, L . A . and H.G. Hopkins. 1937. The forest s o i l of the Douglas-fir region and changes wrought upon i t by logging and slash burning. Ecology 18-2:264-279. Brooklyn, New York. Jacques, F . H . 19^7. L'agriculture des noirs du Cameroun, une forme particuliere de l'ecobuage. Agron. Trop. 2(3/4) :180-182. (Cited  by Ahlgrens, i960).  Jenny, H. and A.D. Ayres. 1939. S o i l Science, 48:44-3. (Cited by Overstreet and Dean, 1953). Kelley, C C . and R.H. Spilsbury. 1939« Soil survey of the Lower Fraser Valley. B.C. Dep't. Agr., Co-op. Exp. Farms Serv., Dom. Dep't. Agr., Ottawa, Tech. Bull. 20, Publ. 650. 67 pp. Kivekas, J . 1939. Kaskiviljelyksen vaikutus erSisUn maan ominaisuuksiin. Comm., Inst. Forest. Fenn. 27(2):l-44. (Cited by Ahlgrens, i960). Krajina, V . J . 1958. Ecological requirements of Douglas-fir, western hemlock, Sitka spruce and western red cedar. Misc. Univ. Publ., U . B . C , Vancouver, B.C. 24 pp. . 1959. Bioclimatic zones i n British Columbia. U . B . C Bot. Series, No. 1, Vancouver, B.C. 47 pp. Kramer, P . J . 1949. Plant and s o i l relationships. McGraw-Hill Book Company, Inc., New York, Toronto, London. 347 pp. LeBlanc, H. 1954. A new approach to the northern spruce regeneration problem. Forestry Chron. 30(4):372-379«  - 108 Lesko, Gy.L. 1961. Ecological study of soils i n the Coastal Western Hemlock Zone. Unpublished M.Sc. thesis, Dep't. Biol, and Bot., U.B.C, Vancouver, B.C. Lotti, T. 1956. Growing loblolly pine i n the South Atlantic States. U.S.D.A. Farmers Bui. 2097. 33 pp. Lotti, T. and Culley, E.D. 1951. Loblolly pine, maintaining this species as a sub-climax type i n the Southeastern U.S. Unasylva 5(3):107-113. Lovejoy, P.S. 1920. Effect of forest fires upon s o i l i n the northern Lake States. Mich. Acad. Sci., Proc. 22:9-20. Lunt, H.A. 1951• Liming and twenty years of l i t t e r raking and burning under red and white pine. Soil Sci. Soc. Amer., Proc. 15:381-390. Lutz, H.J. 1934. .Ecological relationships i n the pitch pine plains of southern New Jersey. Yale Univ., School of Forestry, Bull. 38. . 1956. Ecological effects of forest fires i n the Interior of Alaska. U.S. Dep't. Agr., Tech. Bull. No. 1133. 121 pp. , and E.F. Chandler, Jr. 19^6. Forest soils. Inc., New York. 514 pp.  John Wiley 0 Sons,  Maissurow, D.K. 19^1. The role of f i r e i n the perpetuation of virgin forests of northern Wisconsin. Jour. Forestry 39(2):201-207. Metz, L.J., T. L o t t i , and R.A. KLawitter. 1961. Some effects of prescribed burning on coastal plain forest s o i l . For. Serv., S.E. For. Exp. Sta., Asheville, N.Car.,.Sta. Pap. No. 133. 10 pp. Morris, V/.G. 1958. Influence of slash burning on regeneration, other plant cover and f i r e hazard i n the Douglas-fir region. Pac. N.W.F.E.E.S., U.S. Dep't. Agr., For Serv., Res. Paper 29. 49 pp. Mueller-Dombois, D. 1959* The Douglas-fir forest associations on Vancouver Island i n their i n i t i a l stages of secondary succession. Unpublished Ph.D. thesis, Dep't. Biol, and Bot., U.B.C, Vancouver, B.C. MUller, K.M. 1929* Aufbau, Wuchs, und VerjUngung der SUdosteuropaischen Urwalder. Hanover, M. and H. Schaper. (Cited by Ahlgrens, i960). Muri, G. 1955. The effect of simulated slash burning on germination, primary survival and top-root ratios of Engelmann spruce and alpine f i r . For. Club., U.B.C., Vancouver, B.C. 7 pp. Murison, W.F. i960. Macronutrient deficiency and i t s effect on coniferous growth. Unpublished Ph.D. thesis, Dep't. Biol, and Bot., U.B.C, Vancouver, B.C. National Soil Survey Committee of Canada, i960. Report of the meeting of the N.S.S.C, 22 to 27 Feb., i960. Ontario Agricultural College, Guelph, Ontario. 42 pp.  - 109 Orloci, L. 1961. Forest types of the coastal Western Hemlock Zone. Unpublished Master's thesis, Dep't. Biol. and Bot., U.B.C., Vancouver, B.C. Osborn, J.B. 1931. Some physical properties of wattle s o i l i n Natal. So. Afr. Jour. Sci. 28:207-221. (Cited by Ahlgrens, i960). Overstreet, R. and L.A. Dean. 1953. The Availability of Soil Anions. Chapter 4, 79-105 pp. (Truog, E.:Mineral Nutrition of Plants.) Univ. Wisconsin Press. Pacific Northwest Forest and Range Experiment Station. 1957* Annual Report. For. Serv., March, 1958. Portland, Oregon. 82 pp. Pearse, P.H. 1958. A study of the effects of s o i l compaction on the early development of seedlings of Douglas-fir and western hemlock. U.B.C. For. Club, Res. Comm. Note No. 16, Vancouver, B.C. 7 pp. Pickering, S.U. 1910. Studies of the changes occurring i n heated soils. Jour. Agr. S c i . 3:258-276. (Cited by Rideout, 1949, and Ahlgrens, I960). Rideout, E.F. 1949. A study of slash burning and i t s effect upon a British Columbia s o i l . Unpublished Master's thesis, Dep't. Agronomy, U.B.C, Vancouver, B.C. Salisbury, E.J.  1925.  The vegetation of the forest Wyre. Jour. Ecology  13:314-321. (Cited by Burns, 1952).  Sampson, A.W. 19^. Effect of chaparral burning on s o i l erosion and on s o i l moisture relations. Ecology 25(2):191-195« Schmidt, R.L. 1957* The s i l v i c s and plant geography of the genus Abies in the coastal forests of B.C. Tech. Publ. 1, 46. Dep't. Lands and For., B.C. For. Serv., Victoria, B.C. 33 pp. Seaver, F.J. and E.D. Clark. 1912. Biochemical studies on soils subjected to dry heat. Biochem. Bull. 1:413-427. (Cited by Ahlgrens, i960). Shantz, H.L. 194?. The use of f i r e as a tool i n the management of the brush ranges of California. Calif. Dep't. Nat. Resources, Div. of Forestry. 156 pp. Shirley, H.L. 1932. Does light burning stimulate aspen suckers? Forestry 29(4):524-525; 30(4):419-420.  Jour.  Show, S.B. and E.J. Kotok. 1924. The role of f i r e i n the California pine forests. U.S. Dep't. Agr., Bull. No. 1294. Washington, D.C 80 pp. Sloan, G. McG. 1957. The forest resources of British Columbia, 1956. Public Inquiries Act, Vol. 1 # 2, Queen's Printer, Victoria, B.C. 888 pp.  - 110 Sreenivasan, A. and E.N. Aurangabadkar. 1940. Effect of f i r e heating on the properties of black cotton s o i l i n comparison with those of grey and humus-heated soils. Soil Sci. 50:449-462. Starkey, -B.L. 1959. Microorganisms of the Ehizosphere. Recent Advance in Botany. Botanical Congress i n Montreal, 1959* Vol. I: 601-604. Stobbe, P.C. 1940. -Land classification.  119-127.  For. Chron., Vol. XVI, No. 2:  Suchkina, N.N. 1933. Nitrification of forest soils with reference to composition of stands, cutting and f i r e . Izvestia Akademii Nauk  S.S.S.R.:111-159.  Sttchting, H. 1929. Die Bekampfung des Humus der Waldbbden. Zeitschr. Forst. Jagdwesen 61:349-363. (Cited by Chrosciewich, 1959). Svenhufruid, E.G. 1929. Suon polltoviljekyksen s e l v i t t e l i j U . Suom. Suovilj. Yhd. julkaisija 10. Helsinki. (Cited by Ahlgrens, I960). Swenson, G.W. 1939. Base exchange capacity and moisture equivalent relationships of charcoal i n forest s o i l s . Unpublished Master's thesis, Yale Univ., School of Forestry. (Cited by Ahlgrens, I960). Tamm, 0. 1950. Northern coniferous forest soils. The Scrivener Press, Oxford. 253 pp.  (Transl. M.L. Anderson).  Tarrant, E.F. 1949. Douglas-fir site quality and s o i l f e r t i l i t y . Forestry, Vol. 47:716-720.  Jour.  . 1953. Effect of heat on s o i l color and pH of two forest soils. U.S. Dep't. Agr., For. Serv., Res. Note No. 90. 5 PP« . 1954. Effect of slash burning on s o i l pH. U.S. Dep't. Agr., For. Serv., Res. Note No. 102. 5 pp. .  1956 a. Effect of slash burning on some physical s o i l properties.  For. Sci., Vol. 2, No. 1:18-22. . 1956 b. Changes i n some physical s o i l properties after prescribed burn i n young ponderosa pine. Jour. Forestry, Vol. 54:439-441. . 1956 c. Effects of slash burning on some soils of the Douglasf i r region. Soil Sci. Soc. Amer. Proc., Vol. 20, No. 3:4o8-4ll. __________ and E. Wright. 1955* Growth of Douglas-fir seedlings after slash burning. U.S. Dep't. Agr., For. Serv., Res. Note No. 115. 3 pp. Tourney, J.W. and C.T. Korstian. 1947(1956,a). Foundation of silviculture upon an ecological basis. John Wiley 0 Sons, Inc., New York. 486 pp. Transilla, M. 1962. On the influence of prescribed burning on the temperature and humidity conditions of the s o i l . Abstract of address to the Scientific Session of C. Ag. M. -III. Toronto, July 3, 1962. 6 pp.  Truog, E. 1953. Mineral Nutrition of Plants. 469 PP.  Univ. Wisconsin Press.  Tryon, E.H. 1948. Effect of charcoal on certain physical, and biological properties of forest soils. Ecol. Monogr. 18:81-115. (Cited by Beadle, 1940). Uggla, E. 1957. Mark-och luftemperaturer vid. hyggesbranning. (Sartryck ur). Norrlands skogsvardsforbunds tidskrift nr IV:443-500. Uggla, E. 1958 a. Ecological effects of f i r e on north Swedish forests. Almquist and Wiksells Boktryckeri A.B. Uppsala. 18 pp. . 1958 b. Skogsbrandfalt i Muddus national park. geographica Suecica 4l:5-ll6. Uppsala.  Acta Phyto-  Vincent, A.B. 1956. Balsam f i r and white spruce regeneration on the Green River Watershed. Canada, Dep't. North. Aff. # Nat. Res., For. Res. Div., Tech. Note No. 40. 24 pp. Vlamis, S., H.H. Biswell, and A.M. Schultz. 1955* Effects of prescribed burning on s o i l f e r t i l i t y i n second growth ponderosa pine. Jour. Forestry 53(12):905-909. Waksman, S.A. 1936. Humus Origin, Chemical Composition and Importance i n Nature. The Williams $ Wilkins Comp. Baltimore. 494 pp. Waksman, S.A. and R.L. Starkey. 1931. The s o i l and the microbe. Wiley # Son, New York. (Cited by Lutz-Chandler, 19**6).  John  Weaver, H. 1952. A preliminary report on prescribed burning i n virgin ponderosa pine. Jour. Forestry 50(9):662-667. . 1955. Fire as an enemy, friend, and tool i n forest management. Jour. Forestry 53(7):499-504. Wenger, K.F. and Trousdell, K.B. 1957* Natural regeneration of loblolly pine i n the South Atlantic Coastal Plain. U.S.D.A. Prod. Res. Rpt. 13, 78 pp. Wilde, S.A. 1958. Forest soils. 537 pp.  The Ronald Press Comp., New York.  Wilson, G.W. 19l4. Studies of plant growth i n heated s o i l . Bull. 3(l0):202-209. (Cited by Ahlgrens, I960).  Biochem.  Worley, F.P. 1933. Forest fires i n relation to s o i l f e r t i l i t y . (London) 131:787-788. (Cited by Ahlgrens, i960).  Nature  Wright, E. and R.F. Tarrant. 1957. Microbiological s o i l properties after logging and slash burning. U.S. Dep't. Agr., For. Serv., Res. Note No. 157. 5 PP.  APPENDIX I  Tables I - XXXII  - 113 Table I . C h a r a c t e r i s t i c s of the three places of sample block c o l l e c t i o n . After G r i f f i t h (i960).  Name and Number of S i t e i n the Present Study-  Number of Permanent Sample Plots by U.B.C. - Forestry Faculty Number of P l o t s , used by Lesko-Orloci  Elevation - feet Aspect Slope - per cent Topography  S i t e Index - Douglas-fir - feet Aver. Age - Douglas-fir - 1951 Basal Area - sq. f t . Aver. Height - Douglas-fir Dom. Codom. - feet - 1951  Swordfern  Moss  Salal  I  II  III  S-8  S-3 E-65  S-l E-67 690 '  sw 13  Low slope  180 ( 1 7 7 ) ^ 76.1  1100 SE 8 Central slope 140 76.5  470.1  430.2  156.3  122.5  210 60 60  200 227 187 614  1360 S 25 Ridge top  80 ( 9 4 ) ^ 61.8 186.4 65.4  Number of Trees per Acre Douglas-fir western hemlock western redcedar Total  330  570  180  330  1080  Basal Area i n Square Feet Douglas-fir western hemlock western redcedar Total  424.7 38.4  7.0  470.1  301.2 104.9 24.I 430.2  120.2 38.6  27.6 186.4  Composition by B.A. - per cent Douglas-fir western hemlock western redcedar Total  l/  90.4 8.1 1.5 100.0  Quoted from studies by Lesko and O r l o c i  70.0 24.4  5.6  100.0  (l96l).  64.5 20.7 14.8 100.0  Morphology of soils i n sample collection ditches. 1  II  II  Table I I . 1  - 114  Concretions  P.C  Stoniness  Slope  Soil Group  Aspect  Site  Horizons and Layers  0  B B3 Ach Ah e humic organ- miner- char- eluvBrown lellow ic al coal iated A  II - Moss  I - Swordfern  c  gleyed W Acid Brown Wooded Soils, .4.38  10 15  80$  1 10  Orthic W 0-5 10 100$ (under Humic moss) Podzol,  3.31  H Eluv. Hn) Acid  1,6  SE  20 0 100$  2  80$  2-6  I l  20$  80$  1  5  15+  25$  90$  80$  8  25$  10 75$  5,2 2,15 10,20+  25$  30$  1,2 8  2,5  CO Litho1  H  sol,  5.32  1,8  100$ dark  brown  CE)  M M  2  B  3  diameter-inches  ^-occurrence; range--inches  100$  B  -  2,3  reddish brown  2,5  -  yellowish gray I  2 -  yellowish friable or compacted  -  - 115 Table III.  Permanent numbers of seedling blocks and s o i l blocks. Purpose of sample blocks  Burning rate  Douglasfir seeding  Western hemlock seeding  Western redcedar seeding  Soil analysis (not seeded)  I -- Swordfern site: Severely burned  13  11 1  19 12  10 3  7 14  6 21  20  2  Moderately burned  18  22 8  24 9  23  25  27  16  15  28  17  Unburned control  37 33  40  29  41 38  30  39 42  31  34  32  5  35  4  26  36  II - Moss site:  30  9 4  8 6  1 27  5 28  10 11  7  3  Moderately burned  15 38  22 37  18 29  16 14  25 17  23 26  19  24  Unburned control  36  32 12  20 21  41 33  34  31 13  39  35  Severely burned  2  42  40  III - Salal site: Severely burned  2 ' 5  1 9  3 7  13  14 11  8 10  6  12  4  Moderately burned  27  18  20  23  25 22  16 17  28 26  21 19  15  24  Unburned control  29  36 37  38 31  35 41  32  39 33  42  40  30  Total number Grand total  36  36 seedling blocks - 108  34  36  18 s o i l blocks  - 116  Table IV. Highest temperature during the burning. Degrees of temperature Fahrenheit (Centigrade)  Observation <u  Investigator  Place  Year  I  H fe  CO  CO  2 3  .  § &  §N  O  cd  Below the surface inches 1  2  120 (49)  60 (16)  217 (100)  185 (80)  1924  850 (454)  Elpatievsky, Russia M. P. et a l  1934  1382  Isaac, L . A. & Pacific H. C. Hopkins Northwest  1937  Heyward, F.  Longleafpine Region, U. S. A.  1938  274 (135)  Beadle, N.C.W. New South Wales, Australia  1940  482 245 (250) (118)  Uggla, E.  1957  (750)  i ® og co  6  u  a  a  86  (30)  608 1841 (1000) (320)  2100 (1150)  1000  (540)  30  140 (60)  131 (55)  104 (40)  95 (35)  59 (15)  45  1150  Bentley and Fenner severe burn  California  Bentley and Fenner slight burn  California  Present study simulated severe burn  U.B.C. 1800 1959 2000 (1100) (985) Laboratory (Vancouver)  1958  4  -P CQ  -  CQ  Hoffmann, J. V.Pacific Northwest  Sweden  3  CO  $  (620) 1958  250 (120)  Present study U.B.C. 1959 simulated Laboratory moderate burn (Vancouver)  1250 (675)  780 (416)  200 (93)  35  170 (77)  60 (16)  15  - 117 Table V.  Burning c h a r a c t e r i s t i c s . Temperature  Burning  No.  maximum  S i t e and Use time (min.)  grade  average  at surface  Depth of block  maximum at depth 2" 4"  before the burn  1 1 4 4 4  1 1 4 4 4  1 1 4 4 4 1 1 4 4 4 1 1 4 4 4 1 1  Sw.j Dg.-f. w. h. w.rc. Average S o i l anal. Reserve Sw.j Dg.-f. w.h. w.rc. Average S o i l anal. Reserve Moss; Dg.-f. w.h. w.rc. Average S o i l anal. Reserve Moss; Dg.-f. w.h. w.rc. Average S o i l anal. Reserve Sala l ; Dg.-f. w.h. w.rc. Average S o i l anal. Reserve Sala l ; Dg.-f. w.h. w.rc. Average S o i l anal. Reserve  30 30 30 30 30 30 15  15  15 15 15 15 35 40 35 35  40  40 15 15 15 15 15 15 35 40 40 35  40 40 15  severe  it it ti  severe n moderate n  it  n moderate n severe n  n tt severe  tt  moderate  tt ti II  moderate II  severe II  it I!  severe n moderate  15 15 15  tt tt it it  15  II  15  1705 1720 1785 1730 1770  1950 1095 1208 1290 1198 900 1500 1858 1862 1875 1865 1630 1970 1510 1620 1550 1560 1250 1560 1805  1560 1552 1675 1596 1740 1920  1007  1100 1149 1085 630 1300 1812  1762 1825 1800 1500 1850 1340  1445  1442 1409 1160 1490 1715  578 178 210 322 150 190 121 112 111  115 250 _  248 868 IO45  720  1420 160 208 200  320  242 110 230 1285  90 [ 12.75 .75 77 13.00 1.00 105 13.00 .75 13.00 .75 ?1 70 I 12.25 1.00 13.50 .50 62 12.50 .75 61 12.75 .75 62 12.50 .75 62 12.50 .75 65 12.25 1.00 11.50 .50 175 12.75 1.50 145 12.50 1.50 164 12.75 2.00 161 12.75 1.50 200 [ 12.75 1.75 150 12.75 2.00 65 [ 12.50 1.50 66 12.50 1.50 86 12.00 1.50 72 12.50 1.50 70 12.25 1.25 190 11.75 1.75 6.25 2.50 185 —  —  1802 1720 1775 1930 1660 1060  1705 1320 412 1602 1320 530) 5022 1308 342 1840 1610 970  1510  340 442  210 180 60  1070 887 1005 1060 1350  1010 810 930  228  61  950 1320  140 270 100 260  the burn  inches  Fahrenheit degrees 4 4 4  loss  after  70 64 70 150  5.75 5.75 6.00 6.50 6.00 5.00 4.75 5.00 5.00 5.25 5.50  12.00 12.00 12.25 12.25  11.25  13.00 11.75 12.00 11.75 11.75 11.25 11.00  11.25  11.00 10.75 11.25 11.00 10.75 11.00 11.00 10.50 11.00 11,00 10.00 3.75  2.25 2.50 2.50  3.50  2.50  3.50  1.25 1.50 1.50  3.50  2.50  1.50  1.50 2.00  3.25 3.50 4.00  3.50 3.50 3.50 3.75 3.50  - 118 Productivity of blocks plotted against the rate of burning and r e mains on surface. Blocks are arranged i n decreasing order of productivity i n each group.  r-i  0) CO CO CO  1 H  rt  O f-. O -P  •ri  CD P ft)  f-.  CO T3 O  Mos  CO-*  spoxg  CO  .  r-iO  IBOOJ'Bqo qsv ujng  XBOoaBLio  trol  Conord  (0  u  CO  o  CO IH  CO CO CO  -4  CO  ri  Jjooia  P- V\ OJ CO  CO O H N  -4  CO H OJ CO  II Cvl CO CO  CO OJ OJ CO  oi  2f  -4  cs  CO  O  -4  usv  CO  -4 CO -4  Oi O i  ^ooig  CO O l CO C OJ H  uang JTOoig  -4 OJ CO  *r-i r-i CS  ri  CM CO  LO  CO  O  CO tO - T CO CO CO  r-i CO  O N  ri  -4 -4 CO -4 CO -4  -4 OI rH  OI  CM  Tl s O  Xi to  IO  CO CQ CO CO  u  o  CQ co  O  c  CO C OJs -4 -4 CO LO Oi  CO  -4  -4 CO CO  J3  -4 CO  Ol  COO  OO i i OCO N  -4-  -4 CO  •8 55 •rl  - -P  r!  O  o CH  O O  -4 O l CO-4 O - s O  o fl o  &  O  CO O G CO  Tl  -4  -P  O Ct) CO  CO  -4 -4  HO l  • p >J  CQ  CM s O CO  -4 O l  CO  •cj +3  Xi  CO  CO CO CO H  CO  T3  OH  OI  H  O CO  •H  CO  l > - s O s O ~4 O l H OJ  CM O i  CQ  ct) 0)  •ri O •ri  CO r—j CM r-lCS  O l CO  c •ri  O  II oi CO H  5  c  o  LO  -4 H  -4"  fl°  0  V  r-i r-i  O  CO CO  H  -4 CO -4  -4 CO OJ  t  -4 ~4 -4-  X  CO  o U  CO  U -P CO to u  XI  CD  •P  CO  S  u  r-i r-i rir-i II r-i r-i r-i r-i r-i r-iCS r-i r-ir-iCS r-i r-iCS r-i  CO  CO  CM  CO CO CO CO  -4 OI CO  CO s O O OJ  r—1  -4 -4  uang  leooaBiici  Ol  X co  Ol  Oi  uoxq.BiaH  LT\  S CM  O i CM H CM  CO C— O N CO CO O i CO  CO  O l CO CO -4" CO  X co  r-i  o  r-i r-i  O _  g to 3 ' LO  O sl OCO -4 LO CO ! >  -4 CO CO -4  r-i  o  r-i r-i  H  CO  -p » v  -P  -4  uoxq-Bisy  Yeoojreiio  H  O  CO  -4 CO  O N  N  cs  II -4 -4  I  o  co  CM  •H  r-i Ol  -4 H Q CO CO -4  II  -4  spots  r-i r-i  IO  XI CM O l S to . o  CQ O  -4 CO i-j O r-i H  cS  OJ CO H CO CO  CO rH CM  CO  OI CO O l O i CO O l CO  CM CO  co co -4- co  XBooJceqc  r-i  +3 i r \  CO  -4 CO H CM  -4 C - CO CO  CM  ri  CO  OI  -4 CO  OJ CO CO CO  CO  > CO  ri  r-H  uoxq.'Biaa  Burning  •  cs  CQ  rH O l O l O i  -d- OJ H co  uang  ?  CO  H OJ  O  •H - P -P  -4 Os sOI O CO CO  O l OJ H  CO CO CO -4  o o  Xi to o  OI CO CO -4 CO OI CO  N O  usy u\ing  >  CO •p  LO O l  r-i r-i r-i t—i r-i m -4 -4 -4  s O O l CM O l CO CO - T H  jpoig  gCO  CO O l O i OJ  uoxq.BXSH  -P CQ CO -P  -4 O i  -4 CM CO H  O N  jpoxg  qsv  CO  -4" -4  H  CO  H CO  CM O s -4 CO CO CO CO CO  ri r-i II r-i * r-i r-i r-i r-i r-i r-i co co r-i co r-i C— i—j r-i r-i  UOT^'BT.SH O  -4  CM CO  Jiooig  u  CO CO  CQ  t>  uoxq.«x H  CO  iv-3 l  -4-4  s  CO  CO -P  -4 H  -4COH Ol  fir  H H  usv uang  Douglas-  CQ  H  Ol  Ol rH  cedar  H  CQ  i—1  uoxq.'e-raH  •  <D -P  CO IO CO CO CO  red-  Salal H  xi o  c-  OI CO CO CO  uoxq.-BTSH yeooaHtrn  t CO  N O  western  CO  o  hemlock  CO -p  O S  jpoxg  r-i  OJ  uoxrrex^H  western  ite  Con-  trol  Table V I .  •H CQ  ^  So"  CQ CO -P  I CO  CQ l>»  S  -P  I CO '!> fl  CO -p fl •H fn CO  CO  o o  &  I  >» +5  !> - H O -P 0 O  TS « * CO  II  ^ r-i Tl 1  Cfl O  CO  H O X I  •d V5 • a ^ X! 3  M  o  too CP <£}  cS co  - 119 Table VII.  Month  March April MayJune July August September October November December Sub-total  Water used for irrigation and precipitation at the sample area Amount of watering in experiment  Actual precipitation in the forests inches of precipitation  Averages in the forests for 12 years  I960:  I960:  2.00 1.00 5.25 4.00 3.75 3.00 3.50 3.75 3.75 7.00  6.67 6.58 8.46 3.13 7.03 3.33 10.98 9.02 7.02  9.80 5.62 3.50 4.72 2.81 3.10 4.17 9.04 11.34 14.43  37.00  62.22  68.53.  1261:  1961:  -  1946 to 1957  7.50 7.00 7.00 4.75 1.75  20.10 23.12 9.86 6.37 5.64  12.22 10.58 9.80 5.62 3.50  Sub-total  28.00  65.09  41.72  TOTAL  65.00  127.31  110.25  January February March April May  Notes:  Field data of precipitation are taken from records of the Meteorological Station at the Administration Building, Haney Research Forest. Averages for 12 years represent data for the same region, from the period 1946 - 1957.  Table V I I I .  Adjusted per cent germination on groups of four blocks, Hay, I960. S  M  u Mean  Species burning rate I. Douglas-fir western hemlock western redcedar Mean  100 69 52 78  92 84 32 69 " II.  Douglas-fir western hemlock western redcedar Mean  88 78 41 69  Total mean  90 68 32 63  94 77 39 70  92 31 29 51  92 55 36 61  Moss site  97 57 37 64 III.  Douglas-fir western hemlock western redcedar Mean  Swordfern site  Salal site  95 98 27 73  86 84 32 67  49 70 32 50  77 84 30 63  73  67  55  65  -  121  Table IX. Average values of seedling development on each group of twentyseedlings, December 30, I960.  Severely burned blocks Species  •  H  B  D  1 1 L  I  Moderately burned blocks H  B,  I. D H C  1 265 »  256 162  11 16 9  4.0 3.2 2.5  40 —  10  205 228 147  S 204 241 1 50  8 16 4  3.2 3.1 1.1  -  20  9 15 8  III. D H C  1 136  1 1  181 153  Legend:  4 11 8  2.0 2.3 2.6  55  213 298 283  B  D  L  3.5 3.0 2.1  5  82 73 65  1 6 4  1.5 1.4 1.4  75 10 5  15 10 10  352 233 154  14 15 8  4.5 3.3 2.2  65 1°  150 167 158  5 11 8  2.3 2.4 2.7  40 30 35  20  Moss s i t e 10 15 7  233 251 126  H  L  Swordfern s i t e  II. D H C  D  Unburned blocks  10 18 11  3.4 3.3 2.0  -  Salal site 3.2 3.6 3.6  -5 80  H - height, cm.; B - no. of primary branches; D - stem diameter, mm.; L - per cent of seedlings with lammas growth.  - 122 Table X.  Fresh weight of twelve seedlings on each group, July 8, 1961.  Moderately burned blocks  Severely burned blocks S  R  P  S/R  P  R  S  | | S/R|  Unburned blocks  S  R  P  S/R  grams I. D H C  Swordfern site  318.40 194.50 512.90 1.64 217.75 171.60 389.35 1.25 288.72 159.25 447.97 1.79 264.87 149.37 414.24 1.73 177.60 230.63 408.23 0.77 159.95 172.55 332.50 0.92 II.  31.38 23.34' 54.72 1.32 56.87 27.15 84.02 2.09 53.70 21.15 74.85 2.54  Moss site  D [154.39 112.80 267.19 1.371211.60 153.35 364.95 1.38 J417.77 201.00 618.77 1.28 H 1174.90 114.03 288.93 1.53 185.40 111.11 296.51 1.67 422.04 187.72 609.76 2.25 C 1 76.20 94.05 170.25 0.81I165.48 212.43 377.91 0.78 222.95 245.47 468.42 0.91 III. D H C  Salal site  70.98 68.10 139.08 1.04 192.05 118.50 310.55 1.621147.35 106.05 253.40 1.39 94.43 66.58 161.01 1.41 268.02 134.35 402.37 2.00[187.55 95.32 282.87 1.97 97.75 137.97 235.72 0.71 316.00 321.90 637.90 0.988215.70 173.67 389.37 1.24  Legend:  S - aerial part; R - root; P - plant.  - 123 Table XI. Water content of seedlings expressed as per cent of dry matter. Computed from the weight of twelve seedlings i n each group. Variant  Severely burned  Douglas-fir: -p  o  •p  o o  CO  -P  I Site ' II " III » Total I Site II " III » Total I Site II " III " Total  Moderately burned  Unburned control  Per cent 242 292 382  281 307  263  150 155 22k 150 179 200 213 190  281 138 145 149 144 185 194 190 187  291 304 379  268 297 267  142 136  128 143  298 228  m  258  107  155 15-2 148 156* 172 203. 178  western hemlock: •p  o o « -p  o o  CO  •£  c  I Site II « III » Total I Site II » III » Total I Site II » III " Total  m  m  141 181 182  210 185  287  m  133 171  184  166 170  305 245 298 265 149 156 167  152  184  . 178  198  184  western redcedar: •+*'  o o  -p w  Co O rj -P  cd  I Site II » III » Total I Site II » III " Total I Site II » III " Total  420 443 464  367 451  267 393 393 148 157  259 264  393 170 146 160 15_9 246 258  280  245  156 158  162 159  282  222  237  410  184  167 174 244 254 241  OtEd  oao  O  o o o • •• V*) VJl VJl  o o o  O O O • • • -p- CO CO VJl - 0 O  00 O N  O H • •  • • • IV)  o  ON  -j  00  H H -p-  VJl VO  -0  H H H  CD  o  —-3  N O  _  CD  H O  CD  cr  O H H • • • - O  cr CD  VJI  O H H • « •  H •  P  Species  CC O  >i H  o «<|  O N  H CD  o o  P  H M M • o • - 3 O N IV) O VJl O N  H IV) IV) • • • VJl NO IV) -<] VO .p-  O O  O O O • • • •p- NO ON O O  H H  o o o  O H H • • •  If  • -J  O  • a CO 00  O-O  H  O IV) H • • • vO O ON  00  ow  H H M CO  P. P  -J  ONVJO  CO -0 00  VJI  co ca  co  00  H  O H H • • » NO - 0 IV) ro vo  VJI  H-  c+ CO  • •• 00 VO  ON  • • • NJ-^M NO  IV)  J>  O N  00  H -J  o p-  c+ H-  co o cr X o  H  f ft CD  o p. CD •1 a* P> H c+ o CD o  t«r ^ CO  co H M M • • •  p CD  ON  VJI  • c+  CD P-  • ••  VO  cr o  C§ o c+ CtCT  co cr  -P-  H M M • • • £ - -3 H vO.p-.p-  O)  Hc+  CD  CD  a.  CD H C*S  cr  Hi  CO CD CD  <+ a-  H  cr  • co P p. 4 _ <! cr CD «<S co  C*" P . CD  p. o  s: Ci CD  o o o  • •00 •  VJl s O  M f - H  H H H • • • M  -p-  vO VO - J NO  IV) IV)  •  •  M •  IV) NO VO V J J -O H  o o o  • • » VJI  CO vO  N O VJl V O  O IV) H • • • N O  H H  IV) IV) VJI  o>  •  VO |V) • a  •P-  VO IV)  —3 O —3  o o o • ••  M -vi  VJl  M •  M H • • O VO NO M  VJl •P-  O N  c.m I H-  cr  •P*"  H  ' - N  00 NO  o H  cr M • • • -O .p- VJl VJl H 00 VO VO  M •P-  - 125 Table X I I I .  Size of two-year-old wild seedlings from the sample areas, June 2, 1961. Length og  Species  u  Stem  S/R U -ri CD H raRoot f i r s t second CD whole range tio CD year year S3 CQ  £} XI  mm.  Douglas-fir, on open western hemlock western redcedar Total  8 67.37 46.12  34.50  80.62  10 86.2  44.8  29.6  74.4  western hemlock  10 47.7  21.5  23.6  45.1  Total  —  3  CO O O H Q CQ CO CD > CO CO  s rd  1.19 1.00 17.87  87  0  1.58 1.50 27.36  43  4  1.40 1.00 15.00  14  2  1.22 0.40  0 1  —  —  44.6  52, 84 40, 54 37, 55  0.86 0.50 16.50  0 0  0.95 0.25 13.70  0 0  1.00 0.25  0 0  60, 85 32, 70 35, 75  1.06 0.55  20.9  0 0  0.84 0.37  11.6-  0 0  -  0 0  —  25  III.  Salal site  Douglas-fir  10 65.1  43.5  25.4  68.9  western hemlock  10 42.9  27.6  23.3  50.9  western redcedar  10 37.4  Total  CO  Moss site  Douglas-fir  5 44.6  CO CO  -p &  O CO CO  c +5 CD C P,  CO CO CO H  mm.  70, ?5 14 83.10 59.43 72.07 131.50 90, 180 7 61.00 43.00 42.43 85.43 65, 100 10 62.40 20.13 30.87 51.00 42, 67 39 II.  western redcedar  -P  SI  Swordfern site  I. Douglas-fir, shaded  co  0  co si •rJ " M  30  —  —  53.7  0.70 0.30  - 126 Table XIV.  Weight of twelve wild seedlings and their water content from the sample areas, June 2, 1961. Fresh weight  Species  Shoot  Root  Dry weight  Plant S/R  Shoot  grams  Water content  Root Plant S/R grams  P«sr cent  Swordfern site  I.  Douglas-fir, 1.934 .600 2.534 3.221 .788 .427 1.216 1.84 shaded Douglas-fir, 14.418 2.298 L6.716 6.28[4.588 1.580 6.168 2.91 on open western hem- 4.183 .617 4.800 6.7811.467 .509 1.976 2.89 lock western red- 1.020 .210 1.230 4.861 .445 .142 .587 3.71 cedar II. Douglas-fir western hemlock western redcedar  1.044 .594  .264 .108  .408  .048  1.134  .438  .756  .150  145  40  110  272  45  171  185  21  143  129  48  110  107 150  18 48  79 126  68  25  64  .899 1.851 .94 .524 2.82 168  39 23  75 122  .22  67  Moss site  1.308 3.95 | .505 .224 .729 .702 5.50 .238 .073 .311 .456 8.50  III. Douglas-fir western hemlock western redcedar  Shoot Root Plant  1.572 2.59  .243  .038  .281 6.31  Salal site .583  .962 .204 1.166 4.72 .359 .906 5.03 .419  .316 .165  .123 .542 3.39  81  - 127 Table XV.  Dry weight of twelve seedlings from unburned sample blocks and from the f i e l d .  Site, Species  Unburned block  Field grams  Increase in dry weight (factor)  Swordfern site: Douglas-fir western hemlock western redcedar Sub-total  3.4  20.98 29.56 27.36  6.17 1.98 O.59  15.0 46.0  77.90  8.74  9.0  Moss site: Douglas-fir western hemlock western redcedar  228.20 219.26  0.73 0.31  136.27  0,28  368 710 487  Sub-to t a l  583.73  1.32  483  83.67 94.95  93 182  Salal site: Douglas-fir western hemlock western redcedar  109,83  0.90 0.52 O.54  Sub-total  288.45  1.96  H7  333  7.80 2.81  43 122 194 79  367  By species: Douglas-fir western hemlock western redcedar TOTAL  344 273  1.41  950  12.02  -  128  2 CO  u  Douglas-fir  CO !> CO CO  CD  •p  B CO  Tl  g  H  o U  o o CO  western hemlock  u CO CO CO  -p  nJ U  CO  T3  o  a  r-i O  U  •P  a  o o  CD  western redcedar  U  £ CO CQ CO  -P  «  CO  i H O  -P C  o  O  Burning index  Permanent no.  Index of development o Height growth o o H O N  N O  > • •H IT L 3 >>  cn  H  I  3 4 5 11 1 i 4 3 2,3 2 5 2 4 13 4 1 3,2 3 1 1 1 Grcsup 8 2 3 4 22 4 4,3 1 18 2 3,4 3 1 1 2 17 2 Grc5UP 3 2 2 37 1 29 1 33 3 3 40 4 4 Grc3UP 2 3 1 1 3 4 2 2 2 10 1 12 3 3 19 3 4 4 Grc3UP 3 2,3 2 25 4 3 2 1 1 9 24 4 3 3 1 23 2 4 2 Grc3UP 2 1 1 41 2 30 4 3 38 2 4 35 3 Gr<5UP 1 1 21 1 2 4 3 14 2 3 4 1 7 3 2 1 6 4 1 2 Grcpup 1 1 1 27 o 2 3 16 *— 4 4 26 3 3 2 4 4 2 1 Grc>up 2 1 39 1 31 4 42 3 3 36 4 2 Gr<3Up 3 3 1  N O  o CO Q  § CM  •  7  2 1 4 3 1 2 1 4 3 2  1 2 3 4 1 3 4 2 1 2 1 2 3 4 3 1 2 3 4 1 1 2 4 3 2 1 2 3 4 3 1 2 3 4 1 1 2 4 3 2 1 2 3 4 3  2 3 4 3 1 2 3 4 1 2 1  3 4 2 1 2 3 4 3 1 2 3 4 1 1 2 4 3 2 2 1 3 4 3  o  o  O N  N O O N  H  N O  N O  H  to CO  o  N O O  H • •p o  o  U  8  1  Per cent of seedlings with resting apex  .  H  o  CD  9  10  11  12  1 2 3 4 1 3 4 1 2 2 1 2 3 4 3  100 100 100 100 100 100 100 100 100 100 40 100 100 100  100 60 100 100 ?0 100 100 100 100 100 60 0 0 0  100  15  1  2 3 4 1 (100)  0  1  2 4 3 2 (100) 0 1 0 2 50 3 70 4 3 1 (40) 2 0 0 3 0 4 1 (10) 0 1 0 3 0 2 4 (20) 2 1 (20) 2 0 0 3 0 4 3 (5)  0 0 0 20 40 15  80  100 100 95  100 80  100 100 ?5 100 100 100 80  ?5 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100  0 (100)  H  H  N O O N  N O O N  H  •  H 0)  u  14 100 100 66 100 100 100 100 100 90 100 66 100 33 100 100 100 100 100 75 100 100 100 100 100 0 100 100 100 100 100 0 100 100 100 100 100 0 100 100 100 100 100 0 100  Per cent of Dale seedlings  1  a  u  Growth phase, number  1  Burning rate  Species  Table XVI. Seasonal changes on blocks. In Column 3 blocks are arranged i n decreasing order of production. Index I denotes highest values, 4 the lowest. A. Swordfern site:  £?  15  16  17  16  o  N O  O N  H  o  N O O N  .  H  o  CO  0  0  0 0 0 25 25 10  0  0  0  0 40 40 40 40 40 60 60 60 60  0  0  0  0  0 (100)  0 (100) 60 30 30 30 30 0 (100) 30  0 (100)  (100)  0  0  0  H N O O N  H H •H  0 0 15 0 0  0 0 0 0 15 5 25 25 25 25 25 25 25 25 25 25  5  5  3  3  3  0 25 25 25 25 25 25 25 25 25  3  25  3  very dark  3  3  - 129 Table XVI. Continued.  1  2  CD  CO  i  5  6  7  8  9  2 4 9 30  2 3 1 4'  37 15 22 38  4 2 1 3  1 2 4 3 3 4 3 1 2 2 1 4 2 3 1 4 3 2 1 1 2 3 4 1 2 2 3 4 1  1 1 4 2 2 3 3 4 3 ~3 l 2 4 1 2 4 3 3 2 2 1 1 3 3 2 2 4 4 1 1 1 1 3 2 4 4 2 3 2 2 1 1 2 2 4 4 3 3 1 1 4 4 1 1 2 2 3 3 3 3 3 1 1 2 2 3 4 4 3 3 1 1 2 2 3 3 4 4 2 2 1 1 2 2 3 3 4 4 1 1  2 1 3 4 3 1 2 3 4 2 1 2 3 4 1 1 2 3 4 3 1 2 3 4 2 1 2 3 4 1 1 2 3 4 3 1 2 3 4 2 1 2 3 4 1  1 100 100 2 100 100 3 100 100 4 100 100 3 100 100 1 100 100 2 100 60 4 100 100 3 100 100 2 100 90 1 100 80 2 100 80 3 100 100 4 100 80 1 100 85 2 1 4 3 3 (100) 0 1 2 4 3. 2 2(100) 0 1 20 2 0 0 3 0 4 1 0 5 1 2 3 4 0 0 3 1 (40) 2 0 0 3 4 0 2 (10) 0 1 (40j 2 0 0 3 4 0 1 Jio) 0  -  Group  — —  Grc up  |a  8 6 27 1  4 2 3 1  18 -p 29 16 S 14 CO  3 1 2 4  20 41 21 33  --  5 CO 10 u 28 % 11 CO  2 3 4 1  25 23 17 26  1 2 3 4  34 31 -P c 40 o 13 o  --  CO  u CO > CO  co  Group  CO  Group  o u -p c o o  CO  CO  -p CO  u  CO  —  —  Group  Group  Group  o  u  10  4  36 o 32 u 42 o 12 o  Moss site:  3  Group  -P cd U  B.  —  Group  ?  1 2 3 4 3 1 2 3 4 2 4 2 3 4 1  11  •  12  0  0 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100  (100)  (100)  (ioo)  13 14 15 16  100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 0 100 100 100 100 100 0 100 100 100 100 100 0 100  66 66 100 100 85 100 66 100 66 85 100 100 100 100 100  15 0 15 0 0 10 0 0 0 15 0 5 0 0 15 0 0 15 50 0 50 0 50 15 50 10 50 50 50 50 50 0 50 30 30 30 30 30 0 80 80 80 80 0 (100) 80 0 40 40 40 40 0 (100) 40 0 25 25 25 25 0 (100) 25 0  17 15 0 0 0 5  0  0 25 25 25 25 25 100 100 100 100 100  0  0 25 25 25 25 25  0  18  130 Table XVI. Continued. C. 1  2  0  u  u  •H <H  1  10 CO H $ O  a  CD > CD CQ CD P CO ri CD Tf  i  H O  c-. a o o  -P  CD  western hemlock  U  CD > CD CQ CD -P CO  U  CD XS  i  H O  fn  -P C  o o CD  western redcedar  U  CD > CD CO CD -P CO  U  CD Xi  i  H  |  o o  Salal site:  4  5  6  7  8  9  10  9 3 5 2 1 4 2 1 Grcu p 18 4 3 27 20 1 2 23 Grou p 29 30 36 37 Grou p 4 4 7 2 13 3 1 3 Grou p 1 25 4 22 16 2 17 3 Grou p 38 35 31 41 Grou p 14 4 3 8 1 11 2 10 Grou p 19 4 26 2 21 3 28 1 Grou p  4 1 3 2 1 1 2 4 3 2 4 2 2 1 3 4 1' 2 3 1 3 1 2 4 3 3 4 2 1 2 1 2 3 4 3 4 2 3 1 2  1 2 3 4 2 2 1 3 4 1 1 2 4 3 3 2 1 3 4 2 2 1 3 4 1 1 2 3 4 3 4 2 1 3 2 4 3 2 1 1  1 2 3 4 3 2 1 3 4 1 1 3 4 2 2 2 1 3 4 2 1 2 3 4 1 1 2 3 4 3 1 2 3 4 3 3 4 1 2 1  1 2 3 4 3 2 1 3 4 1 1 3 4 2 2 2 1 3 4 3 1 2 3 4 1 1 2 3 4 2 1 2 3 4 3 1 3 2 4 1  1 2 3 4 3 2 1 3 4 1 1 2 3 4 2 1 2 3 4 3 1 2 3 4 1 1 2 4 3 2 1 2 3 4 3 1 3 2 4 1  100 100 100 100 100 100 100 100 100 100 100 100 100 100 100  5 20 0 40 60 30  (100)  0  (100) 0 40 40 100  0  32 39 34 33 Gro  1 2 3 4 1  1 2 3 4  1 2 3 4 2  1 2 3 4 2  1 (80) 2 (20) 3 (20) 4 (40) 2 - W  3  J  11  ^  0 20  0  12  13  14  15  16  17  18  100 100 100 100 100 100 80 100 100 ?5 80 100 60 40 60 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100  100 100 100 100 100 100 100 100 100 100 100 100 100 100 100  100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100  0 0 0 40 10  15 0 0 0 5  0  4  0  0  0  4  0 100 100 100 100 100 0 0 0 0 15 0 0 5 0 0 0 30 0 10 0 15 0 15 30 0 (100) 0 15 0 15 15 15 0 (100) 0 10  0 100 100 100 100 100 100 100 100 100 100  (100) (60) (60)  (55) (60) (80) (80) (100) (80)  0 (100)  0 (100)  0 (100)  0 (100)  0 0 0 0 15 5  5 5 5 5  0  0 100 100 100 100 100  very dark  0  if  3  3  3  3  3  - 131 Field s o i l samples from the collecting ditches, August, 1959.  Label mark  | p  Table XVII - A.  Occurrence Thickness or on the diameter area  Horizon or selection  per cent I.  Colour  particles to 1.98  Consistency  ML  inches  per cent  Swordfern site—Gleyed acid brown wooded s o i l , 4.38(1960)  Aspect - South; Micro aspect - West Slope - Lower, 10$; Micro slope - 15 per cent; Stoniness - 20 per cent  2 3 4  0 & Ah—shallow 0 & Ah—deep A charcoal Ae Bhfcc  70 30  5a 5b  Bhfc Bfc  70 30  la lb  II.  80  20 90  2 5  £ to.|  1/8  10+  dark brown brown dark gray light gray dark brown  5 to 3 reddish brown 1 to 6 yellowish red  friable friable lumpy, powdery loose loose with concretions cemented cemented  76.8  73.7 100.0  89.5  65.5  72.6 62.6  Moss site—Orthic humic podzol, 3.31(1958)  Aspect - Southwest; Micro aspect - West Slope - Central, 15$; Micro slope - 5 per cent; Stoniness - 10 per cent  6 7  8 9 10a 10b  0 & Ah A charcoal Ae Bhfcc Bhfc Bfc III.  100 25 25 90 80 20  1' to 6 1/8 to i 1/8 to | 2 to 10 2 to 6 2 to 5  dark brown fibrous dark gray lumpy, powdery light lo ose brown friable yellowish red cemented yellowish gray cemented  100.0 100.0  91.4  66.4  60.6 57.6  Salal site—Eluviated acid lithosol, 5.32(1958)  Aspect - Southwest; Micro aspect - Southwest Slope - Ridge top, 25$; Micro slope - 25 per cent; Stoniness - none  13 14 15 16 17 NOTE:  0  A charcoal Ae Bh—common type Bh—deep type  100 75 25 30 10  2 to 8 \ to $ 1/B to h 1/8 to I 10+  black dark gray gray dark brown brown  sticky lumpy, powdery loose loose loose  100.0 100.0 91.7 90.6 90.3  Micro aspect and micro slope refer to the factual position of sample ditches. General topography i s presented i n Table I and s o i l morphology i n Table I I .  - 132 Table XVII - B.  Analyzed samples of s o i l blocks extracted i n June, I960, and July, 1961. (first series).  Label mark  Burning Horizon rate or and Layer selec- producBlock tion tivity I960 1961 I. 20 15 34  Thickness Colour inches Swordfern site  0, Ah severe X Bh X X Bhfcc 0,Ah,Ae moderate Bhfcc XX  1 2 3 1 2  5 6 7 5 6  1 2 3  5 0, Ah 6 Bh 7 Bhfcc  unburned X  II. 7  1 2 3  5 Ah, Ae 6 Bh 7 Bhfcc  19  1 2 3 1 2 3 4  5 6 7 5 6 7 8  39  Ah, Ae Bh Bhfcc 0, Ah Ah, Ae Bh Bhfcc  severe X moderate XX unburned X X X  III.  1.25 dark brown 4.00 6.00 4.00 7.25  reddish brown yellowish brown dark brown yellowish brown  1.50 dark brown 3.00 brown 8.00 yellowish red  1.00 dark brown 3.00 reddish brown 7.00 yellowish red  loose firm with concretions 1.00 dark brown loose 2.00 yellowish red firm 8.00 brown firm 2.00 dark brown loose 2.00 grayish brown loose 4.00 reddish brown firm 5.00 yellowish brown with concretions  80.3 68.2 61.9 69.1 62.0 83.2 69.7 ^ 57.7  94.4 76.5 64.3 96.3 90.4 60.0 89.0 67.0 57.8 49.7  Salal site  1  5 0  severe  1.00 black  15  2 1  6 0, Ah 5 0  X moderate  3.00 black 1.50 brown  42  2 1  6 0, Ah 5 0  X X X unburned  2.25 black 3.00 brown  2  6 0, Ah  NOTE:  loose friable weak cemented loose with concretions loose friable with concretions  Moss site  6  XX  Fine particles to Consistency 1.98 mm. per cent  3.50 brown  organic laininated sticky organic laminated sticky organic fibrous sticky  100.0 96.2 100.0 97.9 100.0 90.0  Decreasing number of asterisks denotes decreasing final productivity in the experiment.  - 133 Table XVII - C.  (second series) Fine  Label mark Layer  Block  July, 1961.  I960 1961  Burning Horizon rate or and selec- production tivity  Thickness  1 2 1 2 3 1 2 3  28  32  5 6 5 6 7 5 6 7  1 2 3 1 2 3 1 2 3 4  24 35  5 6 7 5 6 7 5 6 7 8  Ah, Ae severe 2.50 dark brown Bh x x 10.50 yellowish red Ah, Ae moderate 4.00 dark brown Bh X X 3.00 yellowish br. Bfcc 4.00 yellowish red unburned 0, Ah 1.00 dark brown Bh X 3.50 brown Bhfcc 8.00 yellowish br.  severe X  X X  X  X  l  NOTE:  5 6 5 6 5 6  X  0 severe 0, Ah moderate 0  Ah  0  Ah  X  X  X  X X  78.6 59.7 78.0 68.8 68.2 86.3 62.4 62.7  dark brown reddish brown yellowish red dark brown reddish brown yellowish red dark brown brown yellowish red yellowish br.  loose firm with concretions loose, organic firm with concretions loose loose firm with concretions  92.0 76.0 59.6 100.0 64.1 59.4 93.7 61.2 58.4 74.8  organic laminated sticky organic laminated sticky organic laminated sticky  100.0 100.0 100.0 100.0 100.0 100.0  Salal site  1.00 2.50 1.50 2.00 unburned 2.00 4.00 X  loose weak cemented loose friable with concretions loose loose with concretions  Moss site  1.00 5.00 4.75 moderate 1.25 0 Ah, Bh 2.00 Bhfcc 6.50 0, Ae unburned 1.25 Ae, Ah 3.50 Bh 4.00 Bhfcc 3.50  0, Ah Ae, Bh Bhfcc  III.  12 - 1 2 1 24 2 40 1 2  per cent  Swordfern site  II.  3  Consistency  inches  I.  2  Colour  particles to 1.98 mm.  brown black brown black brown black  Decreasing number of asterisks denotes decreasing f i n a l productivity i n the experiment.  - 134 Table XVIII - A. pH values of field samples, collected from the soil block ditches i n August, 1959. (measurements i n July, 196l).  Horizon or layer Symbol  Character  Swordfern site Label pH mark  Moss site Label mark  pH  Salal site Label mark  pH  0, Ah  Common upper layer  la  4.6O  0, Ah  Deep,  exceptional  lb  5.10  Achl  Selected charcoal  2  4.70  7  3.45  14  3.75  Ae  Selected podzol  3  4.35  8  4.05  15  3.70  Bhfcc  Common enriched layer  4  5.3O  9  1*25  Bhfc  Selected brown lumps  5a  5.40  Bfc  Selected yellow lumps  5b  5.55  Bh  Very shallow mineral layer  16  4.10  Bht  Deep mineral s o i l on bedrock  17  4.25  Average for the horizon (from underlined values) Range of values  5.18  4.35,5.30  6  3-45  13  3.60  1  4.68  3.45,5.05  3.60  Table XVIII - B.  S o i l pH values of s o i l sample blocks i n June, I960 and 1961. (Example)  (measurements i n J u l y , 196l),  m  Second Series  Burning rate  e of .ivity  F i r s t Series  a  co ty CO CO  1961 sample  I960 sample  a  Label Depth mark (in.) o 3  pH  u  Label Depth mark (in.)  pH  1961 sample  Change in pH  Label mark  Depth (in.)  32,5 6  3.50  1.00  5.30 5.76  8.00 12.50  6.00 5.88  4.00 3.00 4.00 11.00  5.70 5.73  +.33  2.50  6.00 5.84 5.87  +.14  pH  PH  I. Unburned  I960, sample Change in pH Label Depth pH mark (in.)  34,1 2  X  3  34  1.50  3.00 8.00  12.50  5.30  34,5 1.50 5.60 6 3.00 5.60 7 8.00 12.50 5.56 34  Swordfern s i t e  5.25 5.25 5.85  5.47  -.05  -.35  +.25 -.09  32,1 2  32  3  1.00  3.50  4.85  8.00  5.30 5.64  12.50  5.48  32  4.00 3.00 4.00 11.00  5.32 5.48  28,5  5.41 5.40  7  2.50  5.86  7  +.45 +.46 +.36 +.40  (fie! .d valu 35.18)  Moderate  Severe  X  X  X  X  X  15,1 4.00 2 7.25 11.25 15 20,1 2 20  Average  3  1.25  4.00 6.00 11.25  5.90  5.55 5.67 4.80 4.80 5.10  4.96  5.40  15,5  6  15 20,5  4.00 7.25  6.20  11.25  5.91  1.25  6 4.00 7 6.00 20 11.25  +.30 +.20 +.24  28,1 2  5.20  +.40  5.65  +.85 +.50 +.61  2,1 2 2  5.75  5.60  5.57  28  3  10.50 13.00  5.65  Decreasing number of the asterisk refers to decreasing p r o d u c t i v i t y .  5.45 5.53 5.47  6 28  2,5 6 2  10.50 13.00  5.68 5.80  5.83  +.38 +.20 +.39  +.39 +.34  - 136 Table XVIII - C. pH values of some seedling blocks of average productivity, July 6, 1961. (measurements i n July, 1961). Blocks with Blocks with western redeedar western hemlock Burning Label Label Label pH pH pH rate mark mark mark (depth: Sur- Cen(depth: Sur- Cen(depth: Sur- CenBlock Block Block inches) face tre inches) la.ee, tre jinches,), tre Blocks with  f  X  Moderate XX  Severe  29  6.05 6.22  6.21  17  6.18 6.00  6.01  1  6.20 5.80  (12.50) (11.25)-  X X X (12.50)  Total  30  18.05  Av.  5.81 5.90  5.89  9 5.85 5.76 (12.75)  5.77  5.68 5.80 12 (12.00)  5.79  (12.50)  5.83  II. Unburned  (13.00)  4.71 5.90  5.81  Moderate  22 5.37 6.20 (11.00)  6.12  5.96 6.15  6.13  X X X  XX  Severe X  Total  9  (11.00)  Av.  XX  30 (5.00)  5.72  14 6.15 5.65 (11.75)  5.69  (11.00)  17.08 5.69  Moss site  5.03  40 4.17 5.52 (13.00)  5.42  4.62 5.60  5.52  5.38 5.63 17 (11.00)  5.61  1 5.40 5.42 (10.50)  5.42  28 5.15 5.60 (11.25)  5,56  29  (12.50)  6.02  5.32  5.53  4.22 4.30 4.28 31 (4.50)  3.90 4.25 4.17 34 (4.50)  16 4.36 4.27 (4.25)  (3.50)  4.40 4.65 4.60  Severe  5.56 4.75 5 (4.75)  4.92  Av.  6.12 5.68  16  16.59  4.86  Total  5.28 5.70 5.67 31 (12.50)  15.97  20 4.73 4.93 (3.00)  X  ,  18.06  Moderate  X X X  e  4.15 5.10 41 (13.50)  III. Unburned  ,  17.45 5.81  6.02  42  c  Swordfern site  I. Unburned  a  14.38 4.79  Salal site  4.29  4.80 4.42 4.50 7 (4.25)  13.07 4.35  21  3.82 4.28  4.15  11 4.95 4.36 (4.25)  4.49 12.81 4.27  NOTE: The surface sample was collected from one inch upper layer and the central one from the mixture of the remainder. The average for block was comnuted accord-  Deviation of s o i l pH i n seedling blocks from values of corresponding s o i l blocks; (measurements taken July 196l).  1  2  (1959)  4.60  S o i l sp. b l . 5.25 6.20 5.20  (1961)  x  Average  x x  Total  XX  III S a l a l Site Severely burned  Moderate, burned  X  Surface Layer F i e l d sp.  Average  XX  x  Total  x x  II Moss Site Unburned control  x  Moderate, burned  Average  x x  Total  XX  Unburned control  X  Severely burned  Sequence  Moderate, burned  Sample  Unburned control  I Swordfern Site  Severely burned  Table XIX.  X  4  3 3.60  3.45 5-55  4.25  5.10  4.50  4.62  4.00 4.60 4.35  4.32  6.14  4.71 5.37 4.15 4.62 4.17 5.38  5.96  5.35 4.72 4.90  4.73 5.56 4.22 4.36 4.80 3.90 3.82 4.96  4.90  Seedl. b l . Douglas-fir W. Hemlock W. Redcedar  6.05 6.18 6.20 5.81 5.85 5.68 5.25 6.12 6.15  5.78 5.84  5.40  5.15  4.40  4.46  4.23  Deviation  + .13 + .21 + .74 + . 2 4 + .22 - . 2 4 + .45 + .43 + .14 -AO -.78 +.6X - r 2 7 -,09  + .46  + .27 +1.46 +2.19 + .73 -.10 - . 4 8 + .90 + .32 + .11 -.08 + .28 + .65 + .85 + .28  + .40  W. Redcedar  -.02+1.00 +1.?8 + .59 + .56 -.35 + .48 + .69 + .23 0 -.08 + .95 + .87 + . 2 9  Average  + .45 -.15 + .81  + .09 + .02 +1.00  + .17 -30 + .42  Douglas-fir W. Hemlock  + .80  + .37  + .37  + .10  Table XIX. Continued. Block Average 1  2  F i e l d sp. 5.18 (1959) S o i l sp. b l . 5.47 5.91 5-57 (1961)  4  3 3.60  4.68 5.65  4.99  5.08 5.17  5.08  4.16 4.53 4.23  4.31  6.02  4.60 4.86 4.92  4.79  Seedl. b l . Douglas-fir  6.21 6.G1 5.83  6.02  5.81  6.12 6.13  W. Hemlock  5.89 5.77 5.79  5.81  5.03  . 5.525.^2  5.32  4.28 4.29 4.50  4.35  W. Redcedar  5.67 5.72 5.69  5.69  5.42  5.61 5.56  5.53  4.17 4.15 4.49  4.27  Deviation Douglas-fir  +.74 +.10 + .25 +1.09 + .36  + .82 +1.04 + .96 +2.82+.94  + .44 + .33 + .69 f l . 4 6 + .49  W. Hemlock  + .42 -.13 + .22  + .51 + .17  + .04  + .44 + .25  + .73 +.24  + .12 -.24 + .27 + .15 + .05  W. Redcedar  +.20 -.19 + .12  + .13 + .0.4:  + .4?  + .53 + .39  +1.35 +.45  + .01 -.38 + .26 -.11 -.04  Average  + .45 -.07 + .20  + .43  + .67 + .53  f.54  + .19  + .19 -.10 + .41  + .17  00  - 139 Table XX - Determination of cation exchange capacity. (Example) F i e l d samples i n 1959; analysis i n May 196l Amount of s o i l - 20 grams. NaOH - 0.1184 Normalities of reagents: . H S04 - O.I98O S o i l sample Mark Site  Burning rate  NaOH used to NaOH H S04 equival. titrate to C o l . 2 excess acid 2  Layer  c c .  2  1 Ah,  shallow  lb  Ah,  deep  2  Charcoal  3  A  la  I  none  e Bhfcc  4  Concretion  5a 5b 6  11  II  none  0  8  Podzol  9  Bhfcc  13 14 15  III  none  0 Charcoal Ae  16  Bh,  17  Bht,  NOTE:  shallow deep  - - factor 0 . 5 9 2  4  3  50 50 25 25 50 50 25 25 25 25 35 25 25  84.40 84.40 42.20 42.20 84.40 84.40 42.20 42.20 42.20 42.20 59.08 42.20 57.25  80 80 25 25 25 25  135.04 135:. 04'. 42.20 42.20 42.20 42.20  70 60 25 25 25 25 25 25  118.16 101.28 42.20 42.20 42.20 42.20 42.20 42.20  Cat. ex. cap. m. equivalent per per 20 g. 100 g. not adjusted adjusted to Col. ( 3 ) norm. minus ( 4 ) ( 5 ) x . 5 9 2 6 5 67.65 67.90 39.70 39.00 39.20 40.75 20.60 21.20 31.70 32.70 45.88 3H.80 30.95  40.05 40.20 23.50 23.09 23.20 24.12 12.19 12.55 18.77 19.36 27.16 20.60 19.78  6.95 7.35 26.70 28.00 10.15 9.85  128.09 128.69 15.50 14.20 32.05 32.35  75.83 76.18 9.18 8.41 18.97 19.15  5.70 4.30 18.25 19.15 1.15 0.90 23.90 23.95  112.46 96.98 23.95 23.05 41.05 41.30 18.30 18.25  66.58 5 7 . 41 14.18 13.65 24.30 24.45 IO.83 10.80  16.75 16.50 2.50 3.20 45.20 43.65 21.60 • 21.00 10.50 9.50 13.20 7.^0 26.30  1  i s the product of the equation -  f = 5 x 0.1184 = 0.592  (normality of NaOH and adjustment to 1 0 0 grams)  Table XXI.  Magnesium and calcium determination. (Example) S o i l block samples i n 1 9 6 1 ; analysis i n June 1 9 6 1 Amount of s o i l analyzed: 2 0 grams Normality of EDTA solution - 0 . 0 0 8 2  S o i l sample Mark Site  Burning 'rate  EDTA  Layer  Aliquot  Mg*Ca  c .c. 1 34,5  I  U  0 + Ah  Bh Bhfcc  34,6 34,7  M  15,5  Ah + Ae Bhfcc  15,6  S  20,5 20,6  Bh  20,7  Bhfcc  39,5  II  U  5  6  4.58  5 5 5 5  9.39 8.69 3.36 O.98  7.00 6.87 2.81 0.62 0.44 3.62 3.31 0.75 O.69 8.62 7.25 2.06 1.60 0.94 0.81  2.39 1.82 0.55 O.36  4.24 1.64 0.48 2.02 1.94 0.53  39,7  Bh  0.42'.  39,8  Bhfcc  0.32 0.44  19,5 19,6  Bh  19,7  Bhfcc S  0.88 0.96 0.72 0.56 0.63  0.52  Ah-+' Ae  7,6  Bh  7,7  Bhfcc  0.33  Mg+Ca =  ;i  5 5 5 5 5 5 5 5 5 5 5 5 5 5 10 10 10 10 10 10 5 5 10 10 5 5 10 10 10 10  0.40  1.13 0.96 0.38  7,5  .  2.20 2.12 0.32 0.30  Ah + Ae  Ah + Ae  m.e. per 1 0 0 g. 4  39,6  M  0.46 0.40  4.14 3.98 1.08 O.98  9.14 8.32  2.40 2.30 1.15 1.10 4.51 4.35 0.66  0.62 0.44 0.32 0.45  0.41 ?0.90 0.98 1.47 1.15 0.51 0.43 2.32 1.98 0.39 0.47 ? .33  ?  .40  O.OO767 x 2 5 0 x 5 x EDTA used  Aliquot  or for  (4)-(5)  Col.  3  4.06 1.17 1.12 0.56 0.54  0 + Ah  Mg  2  0.48 4.46  Ah  oa from Table XXII  0.0082 -  (x)  0.52  .. O.67 0.33 0.29 0.52 1.07 0.34 0.70 0.21 0.29  3.69 3.62 0.12 0.12 0.44 0.31 0.31 0.31 1.12 1.12 0.62 0.62 0.50 0.44 1.81  0.82 0.73 0.54 0.50 0.00 0.00  1.75 0.37 0.37 0.31 0.31  0.23? 0.02 0.10 0.00 0.10  9 . 5 8 7 5 EDTA Aliquot 1 0 . 2 5 EDTA Aliquot  0.14 0.10 • 0.22  0.14 O.85 0.53 0.00 0.00 0.51  -  Table XXII.  S o i l sample BurnMark Site ing rate  Calcium  Layer  1  34,1  I  U  0  + Ah  Bhfcc M'  1 5 , 1  Ah + Ae  1 5 , 2  S  2 0 , 1  Bhfcc Ah  2 0 , 2  Bh 2 0 , 3  3 9 , 1  Bhfcc II  U  0  + Ah  Ah + Ae  3 9 , 2  Bh  3 9 , 3 3 9 , 4  1 9 , 1  M  Bhfcc "Ah + Ae  1 9 , 2  Bh 1 9 , 3  7 , 1  Bhfcc S  Ah + Ae  7 , 2  Bh 7 , 3  Reading Millivolts on scale  Graph value p .p .m.  2  Bh  3 4 , 2  34,3  141  Calcium and potassium determination. (Example) S o i l block samples i n i 9 6 0 (Perkin Elmer Fl.Phm; i n t e r n a l standard method) Determination i n May 1 9 6 l .  Bhfcc  Potassium m. e./ 1 0 0 g. Col. 3 x 1.25 4  3  Reading Millivolts on scale  Graph value p.p.m.  5  6  m. e./ 1 0 0 g. Col. 3 x 1.25 7  5 2 . 8  5 . 0  6 . 2 5  3 . 3  0 . 1 5  0 . 1 9  5 6 . 5  5 . 3  6 . 6 2  3 . 3  0 . 1 5  0 . 1 9  1 5 . 2  1 . 3  1 . 6 2  2 . 3  0 . 1 3  0 . 1 6  1 5 . 2  1 . 3  1 . 6 2  2 . 0  0 . 1 0  0 . 1 3  2 . 0  0 . 2  0 . 2 5  1 . 2  0 . 0 5  0 . 0 6  1 . 6 0  2 . 0 0  1 . 9  0.10  0 . 1 2 *  1 . 5 5  1 . 9 4  2 . 6  0 . 1 2  0 . 1 5 * 0 . 1 0 *  1 9 . 5 1 9 . 0  • •  8 . 2  0 . 7 0  0 . 8 7  1 . 8  0 . 0 8  7 . 5  0 . 6 0  0 . 7 5  1 . 9  0 . 1 0  0 . 1 2 *  5 2 . 6  4 . 7 5  5 . 9 4  3 . 4  0 . 1 5  0 . 1 9 *  55.4  5 . 0 0  6 . 2 5  3 . 3  0 . 1 5  0 . 1 9 *  1 2 . 8  1 . 1 5  1.'44  3 . 2  0 . 1 5  0 . 1 9  1 0 . 4  0 . 9 0  1 . 1 3  1 . 4  0 . 0 5  0 . 0 7  3 . 1  0 . 2 8  0 . 3 5  2 . 1  0 . 1 0  0 . 1 2  3 . 0  0 . 2 7  0 . 3 5  3 . 2  0 . 1 5  0 . 1 9  2 5 . 0  2 . 2 5  2 . 8 1  8 . 8  0 . 5 0  0 . 6 0  0 . 6 0  0 . 7 5 *  2 9 . 5  2 . 5 0  3 . 1 2  1 3 ".'0  1 . 3  0 . 1 5  0 . 1 9  2 . 5  0 . 1 2  0 . 1 5  1 ; 4  0 . 1 5  0 . 1 9  2 . 3  0 . 1 2  0 . 1 3  0 . 7  0 . 0 5  0 . 0 6  2 . 5  0 . 1 3  0 . 1 6  0  0  0  1 . 7  0 . 1 0  0 . 1 2  0  0  0  0.4  t  t  2 1 . 4  1 . 7 5  , 2 . 1 9  4.2  0 . 2 2  0 . 2 7 *  2 3 . 5 .  2 . 0 5  2 . 5 6  3 . 7  0 . 1 8  0 . 2 2 * 0 . 1 5 *  6 . 6  0 . 5 0  0 . 6 2  2 . 5  0 . 1 2  5 . 1  0.40  0 . 5 0  2 . 9  0 . 1 5  0 . 1 9 *  3 . 4  0 . 3 0  0 . 3 7  2 . 4  0 . 1 2  0 . 1 5 *  3 . 5  0 . 3 0  0 . 3 7  3 . 2  0 . 1 8  0 . 2 2 *  1 9 . 6  1 . 7 5  2 . 1 9  2 . 1  0 . 1 0  0 . 1 3  2 1 . 4  1 . 8 5  2 . 3 1  3 - 3  0 . 1 5  0 . 1 9  2 . 8  0 . 2 5  0 . 3 1  1 . 6  0 . 0 2  0 . 0 3  3 . 3  0 . 3 0  0 . 3 7  2 . 4  0 . 1 2  0 . 1 5  0  0  0  3 . 0  0 . 1 5  0.19  0  0  0  2 . 0  0 . 1 0  0 . 1 3  * Determination i n June with samples i n I96I.  .  - 142  Table XXIII.  Phosphorus determination. (Example) Field samples i n 1959; determination i n June Soil sample weight = 5 grams Photometer reading  Soil sample Mark Site  Burning rate  Layer m. volts  1 la  I  none  Ah, shallow  lb  Ah, deep  2  Charcoal  3  Podzol Ae Bhfcc  4  Concretion Bhfc  5 6  II  none  0  7  Charcoal  8  Podzol Ae Bhfcc  9  13 III  none  Graph value  0  14  Charcoal  15 16  Podzol Ae Bh, shallow  17  Bht, deep  1961,  Phosphorus content Col. (3) x  10  p.p.m.  2  3  4  67 68 99 100 76 74  94 93  4.4 4.4 0.2 0 3.2 3.4 2.4 2.2 1.2 1.1 .8 .8  44 44 2 0 32 34 24 22 12 12 8 8  46 4B 63 63 86 84 94 95  7.2 6.8 4.9 4.9 1.9 2.1 0.7 0.7  72 68  44 46 68  7.4 7.2 4.4 5.6 3.2 3.4  74 72 44 56 32 34  81 83  90 91  58 75 74 11 11 22 23  15.5  15.5  10.7 10.3  49 49  19 21 7 7  155 155 107 103  Table XXIV.  Organic matter determination. . (Example) S o i l block samples i n I960; analysis, June 196l  S o i l sample BurnMark Site ing rate  Equivalent  Layer  Soil weight  Used 2  Per  V  T - t Col. 2 7 7 H 0 to (4)titrate (5) the Col.(3) excess  ICCr 0 2  o  F  2  S  V  F  S  7H 0  - 143  2  Col.  (6)xf  to  2  cent  organic matter for the sample  cc. 1 34,1  I  2  U  0 + Ah  34,2  Bh  34,3  Bhfcc M  15,1  Ah + Ae Bhfcc  15,2  S  20,1 20,2  Ah Bh Bhfcc  20,3 39,1  II  U  0 + Ah  39,2  Ah + Ae  39,3  Bh  39,4  Bhfcc  19,1  M  Ah + Ae  19,2  Bh  19,3  Bhfcc  7,1  S  Ah + Ae Bh  7,2  Bhfcc  7,3  4  3  5  6 . 1.90 1.60 2.20 2.50 10.90 8.50 6.90. 7.20 13.60 12.80 16.00 16.40 17.10 13.20 13.20  13.29 11.95 7.70 8.70 3.81 2.97 4.80 5.20 4.75 4.45 11.70 5.72 5.96 4.60 4.60  5.10 4.30 2.50 2.70 9.70  17.84 15.04  0.05 0.05. 0.10 0.10 1.00 1.00 0.50 0.50 1.00 1.00 0.50 1.00 1.00 1.00 1.00  10 10 10 10 10^ 10 10 10 10 10 10 10 10 101' 10  19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80  ' 17.90 18.20  0.10 0.10 0.10 0.10 0.50 0.50 0.50 0.50 0.10 0.10 0.10 0.10 0.50 0.50 0.10 0.10 0.10 0.10 0.50 0.30  10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10  19.80 19.80 19.80 19.80 19.80 19.80 19.70 19.70 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80 19.80  14.70  17.60 17.30 8.90 11.30 12.90 12.60 6.20 7.00 3.80  3.40 2.70 6.60 6.60 15.50 17.30 17.10 10.10  9.40  10.40  11.00 13.10 16.60 16.90 19.10 18.90 10.60 10.20 16.30 15.60 17.60  8.70 6.60 3.20 2.90 0.70 0.90 9.20 9.60 3.50 4.20 2.20  12.30 13.20  7.50 6.60  17.40  7  8.75 9.44 6.79 7.27 6.08 4.62 11.19 10.15  2.45  3.15 6.44 6.72  12.24 14.69  2.40  Equations: % Organic matter  M i l l i l i t r e of N - i ^ C ^ O x O.69 sample grams  of K^C^Oy; % Organic matter = (19.8 - used c c . ) x 0.69 x .505 g. C o l . 7 factor for 1 gr. s o i l = 19.8 - used c c x 0.69 s o i l = 19«8 - used c c x I.38 0. 0.1 g r . s o i l = I9.8 - used c c x 6.90 if  10 cc,  O.OS  o-r.  sri-i 1 ' —  1 Q . ft _  user)  r- . i~  -v "IX  7.70  8.40  5.25 4.62  Table XXV.  Soil sample Mark Site  Burning rate  Layer  1 34,3  I  U  0 0 Ah  34,6  Bh  34,7  Bhfcc M  13,5  Ah 0 Ae Bhfcc  15,6 S  20,5  Ah  20,6  Bh  20,7  Bhfcc  39,5  II  U  0 0 Ah  39,6  Ah 0 Ae  39,7  Bh  39,8  Bhfcc  19,5  M  Ah 0 Ae  19,6  Bh  19,7  Bhfcc  7,5  - 144  Nitrogen determination. (Example) Soil block samples i n 1961; analysis June 1961. Normalities of reagents: E^SO^ - 0.2&78, NaOH - 0.1278  S  Ah 0 Ae  7,6  Bh  7,7  Bhfcc  Soil weight  NaOH equiv. (0.2878) to Col. (3)  H S04 ?  NaOH used to titrate excess acid  Col. (4)(5)  Col. (6)x factor % N  cc.  g. 2  3  4  5  1 1 5 5 5 5 5 5 5 5 5 5 5 5 5 5  10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10  22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50  19.60 19.65 18.30 17.00 20.70 20.65 16.90 17.40 20.15 20.65 l4.4o 13.50 17.50 18.50 18.50 18.50  5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5  10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10  22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50 22.50  13.20 9.30 0.33 12.30 10.20 0.36 20.65 1.85 0.06 20.35 1.15 0.04 20.15 2.35 0.08 19.85 2.65 0.09 20.40 2.10 0.07 19.85 2.65 0.09 21.10 1.40 O.05 21.15 1.35 0.05 20.80 1.70 0.06 21.30 1.20 0.04 18.40 4.10 0.15 2.80 0.10 19.70 4.45 0.16 18.05 18.00 4.50 0.16 5.00 0.18 17.50 18.20 4.30 0.15 18.40 4.10 0.15 3.00 0.11 19.50  6  7  2.90 0.52 2.85 0.51 4.20 0.16 5.00 0.18 1.80 0.06 1.85 0.06 5.60 0.20 5.10 0.18 2.35 0.08 I.85 0.06 8.10 0.51 9.00 0.49 5.00 0.18 4.00 0.14 4.00 0.l4 4.00 0.14  Equation - % N = T - t x (0.1278 x 1.4)/per 1 (for 1 g. soil) = T - t x (0.1278 x 1.4)/per 5 (for 5 g. soil) Factor for 1 g. = O.I7892 x T - t; Factor for 5 g. = 0.03578 x T - t  Sample II  Item  Depth  1 .  2  .  .  Year  3  %  4  pH  5 I.  6  8  •H O  B  •H  •H  0)  to  CQ  r-i  faO id  Si +  (0 (0  ft  + "cd  as milliequival .ent per0 0 100 g . s o i l  7  8  9  10  I960 1961  69.1 5.90 17.28 1.97 6.20 17.38 3.48  Severe; 20,1  ,5  1.25  I960  1961  Change  - . 0 5 +12.66  80.3  11  %  12  0 N  -P  ,_i rt  ft  r\ (0  si  ft  r a t i o ppm 13  l4  15  + .10  4.80 28.47 6.40 5.20 23.72 7.93 + .40 - 4.75  28.2  23  I960 1961  + .30  CD  bO O H  50  1.5  Change  4^ +> r cd «M cd bO cd to O O OU S  a  12.61 0.25 26.3 22.92 0.51 - 8.1 0.52 0.12 2.61 15.1 4.99 0.08 0.59 0.12 4.19 24.1 10.52 0.19 + 9.0 21.1 11.70 0.33 O.85 0.19 7.44 37.6 0.25 8.93 8.75 0.50 0.75  Unburned; 34,1  .5  V  44  76.8 4.60 40.12 9.65 1.52 0.25 11.42 83.2 5.30 24.95 6.43 1.95 0.19 8.58 5.25 37.61 6.93 2.10 O.87 9.90  4.0  t-M« q -p  : ti :  47  1959  Moderate; 1 5 i l  w •* "ho  0.43  2.0  Change  0  •H cd  Swordfern Site  Field, l a  .5  a  iorus  Cation exchange capacity  Exchangeable cations and some other nutrients i n f i e l d samples and s o i l sample blocks. A. SURFACE LAYERS Fine particles up to 1.98 m.m.  Table XXVI.  34.4  +I6.5  20.20  45  - 5 +30 62 16 55 11 -7 -5 35  46  18 62 -52 +16  I  Table XXVI.  Continued. 2  1  3  4  6  5 II.  Field, 6  3.0 1959  Unburned; 39,1  2.0 I960 1961 Change  ,5 Moderate; 19,1  1.0 I960 1961 Change  Severe; 7,1  1.0 I960  ,5  ,5  1961  Change  8  9  11  0  100.0  3.60  13 l 4  15  69.34 1.07 65 16.44 O.30 55 15.21 0.34 45  70  12  Moss Site  2.62 0.41 O.25 3.28 4.31 2.96 0.72 0.62 4.30 12.70 3.66 0.77 0.23 4.66 15.50 + 2.80 2.38 0.57 0.24 3.19 15.60 1.12 0.07 0.12 1.31 11.00 - 4.60 2.25 0.48 0.15 2.88 13.15 I.78 O.36 0.15 2.29 13.10 - 4.46 - 0.05  -10  10.67 0.17 63 2.62 0.05 52 -11 13.46 0.15 90 6.30 0.15 42 -48  31 35 + 4 80 45 -35 61 55 - 6  Salal Site  66.58 6.06 1.66 1.20 100.0 3,. 75 62.87 5.55 1.64 0.79 Unburned; 42,1 4.00 47.73 5.90 1.32 0.27 1961 "••5 Change +.25 -15.14 100.0 4.05 61.57 6.84 3.13 1.15 Moderate; 15,1---• 1.5 I960 1961 4.60 36.56 8.03 2.65 0.37 ,5 Change +.55 -25.01 100.0 4.45 59.81 7.87 2.91 0.81 1.0 I960 Severe; 6,1 1961 4.35 59.27 8.00 2.12 O.50 ,5 Change -.10 - .54 F i e l d , 13  10  3.45 76.00 89.0 4.10 33.77 4.25 30.06 +.15 - 3.71 96.3 4.45 19.44 5.10 11.91 + .65 - 7.53 94.4 4.50 21.84 4.50 17.38  100.0  III.  6.0 1959 3.0 I960  7  8.92 13.3 7.98 12.7 6.49 13.6 + 0.9 11.12 15.20 11.05 29.50 + 5.7 11.59 19.30 10.62 17.90 - 1.4  60.97 O.87 70 82.56 O.30 275 87,26 0.43 203 -72  73 51  19  -32  95.50.-0.27 354 119 62 95.15 0.47 202 •A 51 -57 63.IO O.30 210 95 60.88 O.30 202 61 - 8 -34  I  Table XXVI.  Continued. 2  1  B. ENTIRE SAMPLE BLOCK 3  4  6  5 I.  7  8  9  10  11  12  13  14| 1 5  Swordfern Site  F i e l d sample  12.0 1959  67  5.18 22.57 2.02 1,05 0.09  3.16  1 4 . 0 0 10.33  0.17  60  16  Unburned, 3 4  12.5 I 9 6 0 1961 Change  68  5.56 17.10 1.28 0.49 0.08 5.47 18.58 1.85 0.52 0.25 -.09 +1.A8  I.85 2.62  10.80 14.10 +3.30  5.65 8.05  0.11  51 57 +6  3 8 +5  65  5.67 15.88 1.22 0.28 0.12 5.91 1 4 . 5 5 1.71 0.41 0.11 + .24 -1.33  1.62 2.23  10.20 15.30 + 5.10  4.73 6.38  0.07 0.11  67 68 +1  6 4 -2  66  4.96 17.86 1.35 0.50 0.12 5.57 16.44 1.99 0.13 0.15 + .61 -1.42  1.97 2.27  11.00 13.80 +2.80  5.82 4.92  0.12 0.19  48  8 13 -5  3.81  11.84 20.80  0.33  63 21  0.86 1.16  4.00 6.34 +2.34  8.15 6.32  0.12 0.11  67 7 57 8 -10 +1  8.19 5.83  6.26 5.16  0.09 0.08  69 17 64 1 9 -5 +2  6.55 6.49  0.10 0.13  X  Moderate, 1 5  11.25  XX  Severe, 2 0  X X X  I960  1961 Change  11.25 I960 1961 Change  II. 1959 . • 74  F i e l d sample Unburned, 39  X X X  Moderate, 1 9 XX  Severe, 7  4.68 32.16 0.70 2.96  4.94 21.19 0.50 0.16 0.20 4.99 18.29 0.81 0.22 0.13 + .05 -2.90  11.0 I960 1961 Change  69  4.69 16.96 O.59 0.62 0.18 5.08 14.92 0.55 0.21 0.11 + .39 -2.04  1.39 O.87  70  4.87 11.80 0.30 0.08 0.12 5.17 18.12 0.45 0.08 0.12 + .30 +6.32  0.50 O.65  I960  •  r  F i e l d sample Unburned, 42 Moderate, 15 X  X X  Severe, 6 XX  0.15  61  1961 Change  6.0 1959 6.5 I960 1961 Change 3-/5 I960 1961 Change 4.0 I960 1961 Change  100 95 99 67  III.  26 -22  Moss Site  13.0 I960 1961 Change  11.0  0.14  S a l a l Site  3.60 66.58 3.72 56.13 4.16 49.46 + .44 -6.67 4.05 39.45 4.53 36.70 + .48 -2.75 4.04 46.07 4.23 33.00 + .19 -13.07  3.58 -Q.65  65 49 -16  5 5 0  •  6.06 1.66 1.20 3.77 1.22 O.63 0.25 4.30 0.91 3.40 1.48 O.58 3.94 1.20 0.24  8.92 5.62 5.46  4.12 1.36 0.53 0.23  6.01 3.77  2.91 0.63  -2.36 4.23  5.46  5.38  13.30 60.97 10.00 61.84 11.00 54.57 +1.00 13.80 44.49 14.60 47.31 +0.8C 36.66 11.40 23.79 -1.60  13.00  70 73 21 59 91 28 +70 -31 54 37 0.82 158 0.30 57 fl04 +20 0.32 11 66 0.24 99 46 +88  0.87 0.29 0.60  -20  - 148 Chemical properties of charcoal, A l a y e r , and concretions from the f i e l d i n 1 9 5 9 ? (Analysis i n July I 9 6 I . )  • M i l l i e q u i v a l e n t per 100 g. s o i l  Per cent Per  cent  0  N  Phosphorus  Nitrogen  Organic matter  S + "cd 0  Ratjo ppm  -  Swordfern (Ah layer) 16 Charcoal A Concretion (B layer)  +  Saturation of CaMgK  mm. Label mark . Per cent  Potassium  1.98  Site and item  Magnesium  Fine, particles up to pH  Calcium  Sample  Cation exchange capacity  |  Table XXVII.  2 y  5 4  74  5.10  ' 100 4.70 89 ' 4 . 3 5 73 ' 3 . 5 5 90 , 5.30  23.24 1 . 9 3  3 . 2 9 0.14  23.66 6.68 1 . 0 5 12.37 1.37 0.03 2 0 . 1 9 O.87 0 . 1 2 1 9 . 0 6 0..50 0 . 0 6  12.75  0.24  53  0  7.92 3 3 . 4 16.54 1.51 12.2 2.59 8.36 5.1 0.36 1 . 3 5 O..96 1 . 5 2 7.7 8.71  0.30 0.13 0.12  551 18 63 72  32 23 7 11  4 . 3 69.34 1.07  64  70  296 ' 39  49 20  70  73  6 . 3 5 9 . 5 8 O.36 1 6 5 4.1 3.72 0.07 53  49 34  5.36 23.0  0.19 0.11  0.14  Moss ( 0 layer)  '6'  100  3.45  76.00 2.62 ' 0.43 0.25 3.30  7 8  100 91  3.45 4.05  30.00 3.69 0.15 0.12 8 . 7 9 0 . 2 5 ' 0 . 7 5 0.1'5  4 . 8 35.54 0.12 3.96 1.15 13.0 2.33 0.06  (0 layer)  13  100  3.60  6 6 . 5 8 6 . 0 6 1.66  8.92 13.4  Charcoal A e  14  100 92  3.75 3.70  57.41 13.91  Charcoal A e Salal 1  NOTE;  15  1.20  2.69 0.32 0.55 3.56 0.15 0.26 0.16 0.57  60.97 0.87  \  The surface layers and the B layer are shown for comparison.  Table XXVIII.  C h e m i c a l p r o p e r t i e s o f u n b u r n e d b l o c k s (U) a n d t h e d i f f e r e n c e s f r o m t h e s e t o m o d e r a t e l y ( M ) , a n d s e v e r e l y b u r n e d ( S ) b l o c k s i n i960 a n d 1961. ( D e v i a t i o n by treatment)  Item  Value o f unburned b l o c k s ( U ) , d i f f e r e n c e t o the values o f moderately burned (M), and s e v e r e l y b u r n e d ( S ) b l o c k s Cation Saturation exchange Organic pH of Burcapacity Matter/ C^'Mg^'K ning m.e. p e r Nitrogen rate 100 g. ratio differdiffer- per differdiffer^ per per per ence ence cent ence ence cent cent cent  Site  Surface I.  S e  1.  u e n c e  Positive correlation  layer  Swordfern o Site  o\  vO ON  I I . Moss  Site  o H  H  VO Ov  H  III.  Productivity  Salal Site  o  VO  ON  H H  vO ON  U M S U M S  u M S U M S U M S U M S  (34.4) (5.30) (24.95) +0.60 +11.3 -7.67 -30.7 -19.3 -56.1 -0.50- - 9.4 +3.52 +14.1 -13.3 -38.6 (37.61) (26.3) (5.25) +0.95 +18.0 -20.23 -53.7 - 2.2 - 8.4 -0.05 - 1.0-13.89 -36.9+11.3 +42.9  (50) +12 +24 -15 -30 (45) +10 +22 -27 60  (4.10)  KX jX X| X  Highest N  PCX BC X X  H i g h e s t s a t . and Nitrogen  (12.70) x x (33.77) (55) +0.35 + 8.5-14.33 -33.8 + 2.90 +12.8 + 8 +14, X X Least nitrogen +0.40 + 9.8-11.93 -35.3 - 0.45 + 3.5 +35 +63. X (30.06) x x| H i g h e s t s a t . (15.50) (4.25) (45) 4.50 -29.O + 7 +15- xx| +0.85 +20.0 -19.15 -63.7 x +0.25 + 5.8-12.68 -42.1 - 2.40 -15.4 - 3 - 6 . x  x  (62.87) (3-75) +0.30 + 8.0 1.30 - 2.0 +0.70 +18.6 - 3.06 - 4.8 (4.00) . (47.73) +0.60 +15.0 -11.17 -23.4 +0.35 + 8.7+11.54 +24.1  (12.70) (275) +2.50 +19.6 +79 +28. + 6.60 +51.9 -65 -23. (13.60) (203) +15.90 +116.9 0 0 - 1 .-0. 4.30 +51.6  xx X XX  Highest s a t . X  Table XXVIII  Continued  Entire block I. Swordfern o Site vo O N  H H V O  O N  H  I I . Moss Site o V O  O N  H H V O O N  H  III. Salal Site  o  vo  U"  M S U  M S U M S U M S  u  H  M S  H  M  O N  V O  u  (10.80) (17.10) (51) x + 31.4 XX +G.11 + 2.0- 1.22 - 7.1 - 0.60 - 5.6 +16 + 0.76 + 4.4 + 0.20 + 1.8 - 3 - 5.9 x x Highest sat. -0.60 -10.7 (5.56)  x  (5.47) +0.44 +0.10 (4.94) -0.25 -0.07 (4.99) +0.09 +0.18 (3.72) +0.33 +0.32 (4.16) +0.37  O N  H  +0.07  (18.58) (14.10) (57) + 8.0- 4.03 -16.7 + 1.20 8.5 +11 2.1 r l i _ - 2.14 •11.5 - 0.30 ( 4.00) (67) (21.19) + 4.19 + 2 + 5.0- 4.25 -20.1 +105 + 0.23 2 + 1.4- 9.49 -44.7 + 5.8 ( 6.34) (18.29) (57) + 1.8- 4.37 -23.8 - 0.51 - 80.4+ 7 + 3.6 - 0.17 - 9.2- 2.76 - 43.5- 8 (21) (10.00) (56.13) + 8.8-16.68 -29.7 + 3.80 + 3».0+33 + 8.6-10.06 -17.9 + 3.00 + 30.O-10 (11.00) (91) (49.46) + 8.9-12.76 -25.8 + 3.60 +32.7 +67 + 1.7-16.46 -33.2 0.40 + 3.6 +8  and N  X + 19.2 XX -54.3 x x Highest nitrogen x  x x x  + 3.0 - 3.0  XX X  x x Highest sat, x  + 12.3 XX - 14.0 X Lowest s a t .  XX +157.1 x x Highest sat. - 47.6 x  XX + 73.6 x x Highest s a t . x  + 8.8  and, nitrogen  - 151 Table XXIX.  from i 9 6 0 to 1 9 6 l .  Changes i n chemical characteristics (Change by time)  "t* P m and ning Site rate  Cat. exch. capacity  T  pH  Organic  % satur. of CaMgK  wi 0  p.c.  diff.  p.c.  diff.  p.c.  A  •**  Nitrogen Ratio  m. equ. per 100 g. s o i l diff.  4- 4"  diff.  Productivity  Sequ- Straight p . c . ence correlation  Surface Swordf fern  U  -0.05 -  1.4 +12.66 +50.7 - 8.10 - 2 3 . 5 -  5 - 10.0  X  decreased saturation  M + . 3 0 + 5.1 + .10 + . 1 + 9 . 0 0 +59.6 7 - 10.4 XX S + . 4 0 + 8 . 3 - 4 . 7 5 - 2 5 . 7 + 1 6 . 5 0 + 7 8 . 1 - 17 - 5 0 . 0 x x increased saturation U + . 1 5 + 3 . 6 - 3 . 7 1 - 1 0 . 9 + 2 . 8 0 + 2 2 . 0 - 10 - 1 8 . 1 x x increased saturation M + . 6 5 +14.6 - 7.53 - 3 8 . 7 - 4 . 6 0 - 2 9 . 5 - 1 1 - 1 7 . 5 X X S (3 0 - 4.46 - 2 0 . 4 - 0 . 0 5 - . 0 . 3 8 — 48 — 5 3 . 3 X decreased saturation U + . 2 5 + 6 . 6 . - 1 5 . 1 4 - 2 4 . 0 + . 9 0 + 7 . 1 - 72 - 2 6 . 2 X X increased M + .55 +13.5 - 2 5 . 0 1 - 4 o . 6 + 5 . 7 0 +37.5 - 1 5 1 - 4 2 . 6 5 S X nitrogen .10 - 2.2 X S 8 - 3.8 . 5 4 - 0 . 9 - 1.40 - 7 . 2 x  Moss  Salal  x  X  -  Block Sword- r fern  u  —  .09 -  1.8 + 1.48 + 8 . 6 + 3 . 3 0 +30.5 +  6 + 11.8  X  •  M + .24 +• 4 . 2 - 1 . 3 3 - 8 . 3 + 5.10 + 5 0 . 0 + 1 + 1 . 5 X X s + . 6 1 +12.3 - 1 . 4 2 - 7 . 9 + 2 . 8 0 + 2 5 . 4 - 22 - 4 5 . 8 x x increased nitrogen U + . 0 5 + 1 . 0 - 2 . 9 0 - 1 3 . 6 + 2 . 3 4 + 5 8 . 5 - 10 - 1 4 . 9 x x increased saturation M + • 39 + 8 . 3 - 2 . 0 4 - 1 2 . 0 - 2 . 3 6 - 2 8 . 8 5 - 7.2 X X S + . 3 0 + 6 . 1 + 6 . 3 2 + 53.6 ~:~0.65 - 1 5 . 4 - 16 - 2 4 . 6 X decreased saturation u + .44 +11.8 - 6 . 6 7 - 1 1 . 8 + . 1 . 0 0 + 1 0 . 0 + 7 0 +100.0 X X increased M + .48 +11.8 - 2 . 7 5 - 7 . 0 + 0 . 8 0 + 5 . 8 +104 +192.5 x*x saturation S + .19 + 4.7 - 1 3 . 0 7 - 2 8 . 0 X 1 . 6 0 - 1 2 . 3 + 88 + 8 0 0 . 0 decreased saturation x  Moss  Salal  lqwest saturation  x  Table XXX.  Changes i n phosphorous content as related to pH and the productivity. Moss Site Phosphorus  Swordfern Site Phosphorus >I •  a  pH  Item  »  a  >  ft  0) <D hO O CO  XI O  M  CO ft  •rl  3  4»  +> cr o co 0 co  a  o >» pH ft -rl  6 A.  co a> bo o H ft § h co • xi co o ft © a  > ft  8  S a l a l Site Phorphorus  i > • 3  +> O O •rl  CO  co o >,  3  ^ +> ft -rl  pH  10  H  4*  1  3  a•  i iL  Xi 12  a  +> a* o co 3 (0 •d o  0  CO <t> 60 O  • § u • ft ftO ft  I  CO  •rl  13  Remark to Productivity 14  DIFFERENCE BY BURNING RATE FROM THE UNBURNED CONTROL.  Surface Real value:  u  4.10 31 +0.35 +49 +158.O +0.40 +30 + 96.7  3.75 50 +0.30 +69 +138.O +0.70 +45 + 9.0  Swordfern and S a l a l : Max. i n c r . Max. prod.  Real value:  u  4.25 35 +O.85 +10 + 28.5 ¥0.25 +20 + 57.1  4.00 18 +0.60 +44 +244.4 +0.35 +11 + 61.1  Swordfern and S a l a l : Max. i n c r . Max. prod.  5.30 23 D i f f e r , to • o M +0.60 - 6 - 26.0 OS n tt H S -0.50 +21 + 91.3  D i f f e r , to • ON tt  tt  H  5.25 53 M +0.90 - 4 l - 77.3 S -0.05 + 7 + 13.2  Block D i f f e r , to • ON »i  tt  Real value:  H  H  o D i f f e r , to •vON  tt  tt  5.56 3 M +0.11 + 3+100.0 S -0.60 + 5 +166.6 U  Real value:  X XX  X X X  X 5.47 8 M +0.44 - 4 - 50.O X X S +0.10 + 5 + 62.5X * X  U  4.94  XX x x 3.72 59 7 -0.25 +10 +142.8 X X +0.33 -22 - 37.2 x x -0.07 - 2 - 28.5 X +0.32 + .7+ 11.9X  Swordfern: Max. i n c . - Max. prod. Min. value - min. prod. Moss: Max. deer. Min. prod. 28 x x 4.16 8 Swordfern and XX 4.99 S a l a l : Max. i n c r . +0.09 +11 +137.5 X X +0.37 +29 +103.5 x x Max. prod. +0.18 - 3 - 37.5 X +0.07 +18 + 64.2X Moss: Max. deer. Min. prod. x  x  x  x  1 H  VJI  ro  o  Table XXX.  Continued.  1  2  3  4  5  i {  B.  6  7  8  9  10  11  12  !3  14  CHANGE FROM i960 TO 1961. i  Surface Real value:  Change from I960 to 1961:  43 5.30 23  U -0.05 +30 +130.4 M +0.30 - 5 - 29.4 S +0.40 +16 + 36.3  Block  -  Real value:  Field 3.18 16  u, i960 5.56  Change from I960 to 1961:  3  3.60 73 3.75 50  3.45 70 4.10 31  F i e l d 4.60  u, i960  +0.15 + 4 +12.9 +0.65 -35 -43.7 - 6 - 9.8 0  +0.25 -32 w64.0 +0.55 -57 -47.9 -0.10 -34 -35.7  Moss: Max. i n c . Max prod.  I  i I  4.68 21 4.94 7  3.60 73 3.72 59  U -0.09 + 5 +166.6 X +0.05 + 1 +14.2 x x +0.44 -31 M +0.24 - 2 - 33.3 X X +0.39 + 2 +11.7 X X +0.48 +20 S +0.61 + 5 + 62.5 x^Sc +0.30 X 0 0 +0.19 -20 x  1  -52.5 +54.0 -30.3  XX X X  X  X  Moss: No. i n c . Min. prod. Max. i n c . Max. prod. S a l a l : Max. i n c . Max. prod.  VJO  Table XXXI. Values and per cent changes of chemical s o i l properties which are directly related to the productivity of corresponding seedling blocks. (Asterisks denote productivity by decreasing number). A. Swordfern site. NOTE: Highest productivity i s associated with high value and increase i n pH,in saturation and i n phosphorus content; and with low value of cation exchange capacity and of organic matter per nitrogen ratio; the  Concordant change i n p.c. from I960 to 1961  Trend  Concordant deviation i n p.c. from unburned to burned  Dgl.-fir w.h. w.r.c.  I960  surf, block 1961 surf, block Genera] trend  28.2 14.0  47 60  43 16  to  «  Xi PH  5.90 3 5.67 37.61 6.20 18.58 57 5.91 highhigh low- highest est est +50.70 -23.5 +5.1 +8.60 +12 +4.2 highest  lowest  high  -  -  17.28 15.88 17.38 14.55 lowest  11  12  to  Xi OL,  13  14  15.3 high  high  high  17  37.6  low- highest est  CO  0 u  •  o a X! » o. a. o a, to  «  Xi  18  35  46  48 18  62  26 5.57 16.44 low high- lowhigh est est +8.3 -25.70 +78.1 -50 -7.90 -45.8 +12.3  highest +100  16  11.0  8  13 highest  lowest  +1,8 -36.90 +42.9 -60 +1.50 -11*50 -54  lowest nutritional values  grams grams 21 highly significant 136 30 highly significant 157 27 highly significant 96 d i f f . to both treatments  15  23.72  +59.6 -8.30 +50.0 +1.5 low  pH  «  6  +11.3 -30.70 +2.0 -7.10 +18.0 -53.70 +8.0 -16.70 +8.5  lowest plant production  Total 78  10  9  J§ 1 a, a o a,  Organic matter per nitrogen  40.12 22.57  '  a. a. o a.  s.  Saturation % of Ca"Mg«K'  8  Xi  pH  Cation ex. capacity m.e./lOO g.  7  0 U • o n  Organic matter per nitrogen  6  CO  Saturation % of Ca."Mg"K«  5  Cation ex. capacity m.e./lOO g.  Organic matter per nitrogen  4  1959 surf. 4.60 f i e l d whole 5.18 I960 surf, block 1961 surf, block 5.47 Trend lowest surf, -1.4 block -1.8  Actual concordant values  Dry weight of 12 seedlings of:  3  Saturation % of Ca"Mg"K»  2  1 Actual values  Cation ex. capacity m„e./l00 g.  pH  Severely burned, x x  Moderately burned, xx  Unburned control, x  +91.3 +166.6 +13.2 + 62.5  highest nutritional values near to highest plant production  Total 389  highest plant production grams 184 160  m  Total 458  Table XXXI - Continued.  Chemical s o i l properties versus productivity. B. Moss site.  1 Actual values Actual concordant values  Concordant change i n p.c. from I960 to 1961  2  3  1959 surf. f i e l d whole  6  5  4  76.00 4.31 4.68 32.16 11.84  3.45  I960  surf. block 4 . 9 4 1961 surf. block highTrend est surf. block -13.6 Trend  Concordant devia- I960 tion i n p.c. from 1961 unburned to burned General trend  lowest  Note as before.  7  8  65 63  70  15  14  16  18  17  5  15.50  6.34  -29.5 -28.8  high- highest est  lowest  highest  -29.0 -80.4  5  +53.6  lowest -9.8 0.0  low- highest est  lowest  0.0 +11.7  +158.0 +3 +142.8 -1.4 +15 +12 +137.5  highest nutritional values  highly significant significant highly significant differences to both treatments  3.58 low- highest est  5.83  high- lowest est +22.8 +12.9 +14.6 +14.2 +8.3 +58.5  -5.0  228 219 136  13  90  +64  -28.5 -15.4  -43.5  -37.5  lowest nutritional values near to lowest plant production  highest plant production  Total 583  12  55  grams Dgl.-fir w.h. w.r.c.  11  21  surf. block surf. block  Dry weight of 12 seedlings of:  10  9  lowest plant production  grams  grams  125 104 106  89 102  Total 335  46  Total 237  VJl  Table XXXI - Continued.  Chemical s o i l properties versus productivity. C.  2  1  3  Actual values  1959 surf. f i e l d block  Actual concordant values  I960 1961 Trend  I960 to 1961  surf. block surf. block  Trend  Concordant deviation i n p.c. from unburned to burned Dry weight of 12 seedlings of:  I960 surf. block 1961 surf. block General trend  Total 289  6  7  Note as before. 8  21 59 98 91 low-high est +7.1 +10.0 +100 highest  high  10  9  11  12  13  14  15  16  17  70 73 70 73  3.60 66.58 13.30 3.60 66.58 13.30  surf. +6.6 block +11.8  Concordant change i n p.c. from  Dgl.-fir w.h. w.r.c.  5  4  Salal site.  lowest  119 4.05 39.45 13.80 4.60 36.56 62 29.50 14.60 5.91 14.55 57 highhighlowhighest est est est -2.2 +13.5 -40,60 +37.5 -43 +11.8 +5.8 +54 highlowhigh est est +8.0 +38.0 +8.8 -29.7 +15.0 -23.4 +116.9 +32.7 +8.9 -25.8  0 +244 +103  highest plant production  grams  grams  84 95 110  110 151 189  Total 450  202  highest  high -7.2  -3.8  -12.3 +800  low high- lowest est +138  highest nutritional values near to lowest plant production  59.27  low- high-s est est +24.1 lowest nutritional values lowest plant production  -0.5  grams significant significant highly significant differences to severely burned variants  44  52  61  Total 157  Ov  Table XXXII.  Statistical significance between treatments for average size of each seedling and dry matter production of each block. (See Appendix II.)  Differences between the treatments Site Species  severely burned  severely burned  moderately burned  moderately burned  unburned control  unburned control  Seedling height  Dry weight  Seedling height  N.S. N.S. N.S.  N.S. N.S. N.S.  X X X  N.S. N.S. N.S.  N.S. N.S. N.S.  X  X  X  N.S.  X  X  Dry Seedling weight height  Dry weight  Swordfern site douglas-fir western hemlock western redcedar  X X X  X X X  X  X  X X X  X X X  X X X  X X X  X  X"  X  X  X X X  Moss site douglas-fir western hemlock western redcedar  X X  X  X  N.S.  N.S. N.S.  N.S.  N.S. N.S. N.S.  N.S. N.S. N.S.  N.S. N.S. N.S.  X  X  Salal site douglas-fir western hemlock western redcedar  x  x x  N.S.  X X  X X  X  X  X X  Highly significant at the 0.01 level of probability. Significant at the 0.05 level of probability. No significant difference.  The analysis of variance for height values resulted i n non-significant differences between individual seedlings i n a l l cases except for redcedar on the Salal site.  APPENDIX II Statistical Analyses Example of Analysis of Significance for Stem Heights (cm) of Douglas-fir Individual Seedlings on the Swordfern Site  1. Data for individuals  Block 1  2  3  4  Total  a  59  30  47  50  186  b  56  71  42  34  203  . 4* 48 163 149  46 135  29  171  113  560  Seedlings Severely burned  c Sub-total Moderately burned  a  41  32  42  34  149  b  41  34  26  32  133  c  46 128  46 112  44 112  24 90  160 442  a  19  17  9  9  54  b  16  18  13  6  53  c  1? 54  14 49  8  6  30  21  47 154  345  310  277  224  1156  Sub-total Control  Sub-total TOTAL  Number of individuals in each block Number of units i n each treatment , Number of treatments  46.66  36.83  12.83  3 seedlings 4 blocks 3 burning rates, including the unburned control  - 159 2. Correction factor  C =  = 37120.44  3. Data for blocks and treatments Individual seedling Block  a  b  c  Total  1  119  113  113  345  2  79  123  108  310  3  98  81  98  277  4  ?3 389  72  389  59 378  224 1156  Severe  186  203  171  560  Moderate  149  133  160  442  Control  54 389  53 389  47 378  154 1156  Total  Treatment  Total  4.  Total sum of individuals ss  .  38? + 3 8 j + 378 2  =  2  _  2  6.80  c  5. Total sum of blocks 345 + 310 + 277 + 224 2  S  S  b  l  =  2  2  9 6.  2  C =  882.92  Total sum of treatments  = 560 + 442 + 154 2  2  2  C = 7269.56  - 160 7. Total sum of errors SSer  =  + 47 ) -  (59 + 2  C = 9791.56  2  8. Analysis of variance Source of variation  SS  Individual, ISS  6.80  2  3.40  0.058  882.92  3  294.31  5.048  Treatment, TrSS  7269.56  2  3634.78  6.235  Error, ESS  1632.28 9791.56  28  58.30  Block, TSS  Total  df  MS  F N.S.  **  35  At .01 level of probability F equals 5-45 At .05 level of probability F equals 3.34 9.  t-test Standard error of estimate, Se  = /58.30 = 7.635  Se 7 635 Standard error of treatment, S— = — = \ * • % = 4-408 /n Standard error of difference, S-r = S— x / n - l = S— x ' d x " x  v  Sj = 4.408 x 1.414 = 6.232 Per cent level difference between means for 28 degrees of freedom  t.01 x S- = 2.763 x 6.232 = 17.22 * * t.05 x S-j =  2.048 x 6.232 =  12.76  *  Comparison of treatments:  severe to control  46.66 - 36.83 = 9.83 46.66 - 12.83 = 33.83  **  moderate to control  36.83 - 12.83 = 24.00  * *  severe to moderate  N.S.  Salal  .  ON .  VJI  VJI - J  •p-W M  v o r o -P-  O co r o -P*  . . . NO - 3 NO NO H H  v n 4>- - 0 • • »  —3 VJI . . .  •  • • NO H  - O H M ON M ON O W 00  .  .  00 00 - J  -J  O N ON  H VJJ  .  .  O O  VJI  O  H M VO 0 0 - 0 VJO  .  O  .  . ON  - 0 VJJ  NO  H M M - o -p- -p.  .  .  O H NO - 0  N.S.  N.S.  • . CO CO . .  *  >!<  G O  5|<  *  *  *  >!«  &  &  *  *  *  .  o  VJl  Severe to moderate Severe to control Moderate to control Severe to moderate Severe to control Moderate to control  cr c+  cr CD C+ c+ CD CD CO CD d HJ c+ O  >-i  CD fo c+ CD c+ CD CD CS H c+ R co »-*  ft  £ c+  Hj  o  >i HO CD P3  o  o  HJ  tr  CO CO H - H* c+ OP CD Hj H-  CLfB13 a  CO  XS c+ CD  di  *  .00  •  09 H  an  *  CO «  00-  VJO  Sj< # i  NO •  N.S. N.S. N.S.  *  H H O -0 M  .  Difference  00 M  VO VO  H - C+ H<g CO dt r HCD O V-fu  ni  00  O  VJO O N .  Pc+ H 03  comparison of treatments  NO  . . VO  o  CO N> CD CD CO  % level difference  H  4>  VJl  for 28 degrees of freedom  10.35  13.16  15.75  03-VJI - p . . . NO O NO  J>  -pv n H H  17.22 i c\ An  ( M O W VJl v o  ON  VJI  .  Treatment  . . . -0 - J  ±U.oU  .  .  7.00 23.25 16.25 N.S. 1.16 11.08 9.92 13.84 21.75 7.91 N.S.  i - oa M H H 00. V J I  .  Estimate  oow  14.66  11.38 14.49 19.50  H H •P" O 00  NO  .  ro H M ON-P- O  .p-  VJI  H  CO. £ • *  - O - P - 00  .  o  J>  20.08  15.91  11.39  H H  •  ON J > < 3 . . . ON  O-p- o VJl M VJl  3  its  VJl O •p- r o Vn ON  0>  .  £  standard error  •  CD Cfl  Species  •  o o NO  PO  Site  Douglas-fir western hemlock western redcedar  •  Douglas-fir western hemlock western redcedar  Douglas-fir western hemlock western redcedar VJi 05  -3  Swordfern  Moss  CD H> CO H j CD CD ts  o  CD CO  H  ON  H  Example of Analysis of Significance for Dry Weight of Douglas-fir on the Swordfern Site (each block represents total weight of three seedlings i n grams)  Data Weight for a block (grams) Block  Severe  Moderate  Control  1  57.03  31.76  9.13  2  55.70  31.32  7.33  3  38.52  40.42  2.81  4  32.66  32.91  1.71  Total  183.91  X  +  136.41  +  =  20.98  34.10  45.97  X  341.30  5.245  Number of units i n each treatment Number of treatments  4 3  —  Correction factor  c  =  = 9707.14  Total sum of squares (blocks) TSS  = 2 ( 57.03 +  + 1.71 ) -  2  9707.14 = 4053.18  2  Treatment sum of squares - 183.91 + 1?6.41 + 20.98 4 2  T r S S  2  2  _  c  Error sum of squares  ESS = 4053.18 - 3510.55 = 542.63  _  3  5  1  0  <  5  5  - 163 6. Analysis of variance Source of variation  SS  df  MS  F  TSS  4053.18  12-1 = 11  368.47  TrSS  3510.55  3-1 = 2  1755.27  ESS  542.63  3.(4-1) = 9  60.29  6.16 » 29.11 * *  At .01 level of probability F equals 8.02 At .05 level of probability F equals 4.26 7. t-test Standard error of estimate, Se  = /60.29 = 7.65  Se 7 65 Standard error of treatment, S— = — = -' * £x x/n"  = 4.42  n  x  1  Standard error of difference, S-r = ' d  ,  7  3  2  S— x Jn-l = x v  S— x JT. x v  = 4.42 x 1.414 = 6.249 Per cent level difference between means for 9 degrees of freedom  t.01 x S^ = 3-250 x 6.249 = 20.31 * * t.05 x SJJ = 2.260 x 6.249 = 14.12  *  Comparison of treatments: severe to moderate  45.98 - 34.10 = 11.88  severe to control  45.98 -  5.24 = 40.74  **  moderate to control  34.10 -  5.24 =  * *  28.85  N.S.  Swordfern  Douglas-•fir western hemlock western redcedar  Douglas-fir 6.15 western hemlock 12.91 western red12.79 cedar  Douglas--fir western hemlock western redcedar  7.65  Estimate  -vl - J VO • • • VO .p- VJi 00 V I V 7 I  .ro .ON-p.  Treatment  H • •  row  H  00  NO  ON  •  • •  vn P -0  NO VJJ  5.050 10.900  "7QO  7. (77  O  O 00  •  j> yo 00 N O P  p •p- O  P  •  o vn  P  ro ro -3 oo ro O - O Vn Hf- H  Severe to moderate  * **  Severe to control  H  M  O  P - O  - O  ro ro V J O ro NO vo  W  CO O  O N  ON H  C D  H  TO  Q  N.S. N.S. N.S. N.S. N.S. N.S.  . # CO  . * co  N.S.  *  'r  'i-  •fc  * * * # ##  Severe to control Moderate to control  Moderate to control  HCO  Q  breatments  VO fO VO - J vn CO-  P  compai  fO ->3 VO P Vo H  vrt W 00 ro vo .pp ro o O N vn - J VO H +> Hvoro -O H OO P 00 00 00 O VM  N.S. N.S. N.S.  Severe to moderate  N.S.  -0 vn CO  . . .  Difference  % level difference  i>  ON  oo ON ro 4? 0 4 ? fO O N O H VO M ro p o  for 9 degrees of freedom  Vo H VO M H ro -P- ON O 00 Vo jr-  N O  ro  14.12  • • H ONf-  O  . . .  o~\ on  •  ON  ON  VO vO  8.68  M H ro J>- P M  f-ui O VO VO H  16.31 11.34 34.22 23.80 33.90 23.57  VO Vo H  P P O O Vn • •  .  ro  Hco  <T>  standard error  P •  Site  Spec  Moss  4.71  Salal  APPENDIX III Accompanied Vegetation 1. Natural vegetation on sample blocks at the time of collection, August 30, 1959 Swordfern site blocks Bryophyta:  Eurhynchium oreganum, Mnium insigne, Rhytidiadelphus loreus, Plagiothecium undulatum.  Pteridophyta:  Polystichum muni turn, Athyrium f i l i x - f emina. Pteridium aquilinum, Blechnum spicant, Dryopteris austriaca.  Herbaceous Angiospermae:  Galium triflorum, Viola orbiculata, Trientalis l a t i f o l i a , Epilobium angustifolium, Epilobium adenocaulon, Tiarella t r i f o l i a t a , Senecio vulgaris, Senecio sylvaticus.  Woody Angiospermae:  Rubus v i t i f o l i u s , Rubus parviflorus, Sambucus pubens, Vaccinium parviflorum. Betula papyrifera. Moss site blocks  Bryophyta;  Eurhynchium oreganum, Rhytidiadelphus loreus, Hylocomium splendens, Plagiothecium undulatum.  Pteridophyta;  Polystichum muniturn.  Herbaceous Angiospermae;  Senecio sylvaticus, Senecio vulgaris, Linnaea borealis, Pyrola asarifolia, Epilobium adenocaulon.  Woody Angiospermae;  Vaccinium parviflorum, Vaccinium alaskaense, Rubus v i t i f o l i u s , Gaultheria shallon. Salal site blocks  Bryophyta:  Eurhynchium oreganum, Rhytidiadelphus loreus, Hylocomium splendens, Rhytidiadelphus triquetrus.  Herbaceous Angiospermae:  Viola orbiculata, Holodiscus discolor, Hypochaeris radicata, Epilobium adenocaulon.  Woody Angiospermae;  Gaultheria shallon, Betula papyrifera.  - 166 2. Vegetation on sample blocks nine months after the disruption of natural seepage and two months after burning, May 20, I960 Swordfern site severely burned blocks: 1, 5, 11, 13, with Douglas-fir  Fungi: Spicaria and Coprinus sp. (5). Bryophyta: Funaria hygrometrica-protonema. Angiospermae: Rubus v i t i f o l i u s (from root) ( l ) .  3, 12, 19, 10, with western hemlock  Fungi: None. Bryophyta: Funaria hygrometrica-protonema.  7, 14, 21, 6, with western redcedar  Fungi: None. Bryophyta: Funaria hygrometriea-protonema.  2, 20,  Fungi:  s o i l samples  Bryophyta:  None. Funaria hygrometrica-protonema.  moderately burned blocks: 18, 22, 8, 17, Fungi: Craterellus sp. (18). with Douglas-fir Bryophyta: Funaria hygrometrica-protonema. Angiospermae: Rubus parviflorus (from root)  (8).  24, 23, 25, 9, with western hemlock  Fungi: Ascobolus carbonarius. Lamprospora sp. Bryophyta: Funaria hygrometrica-protonema (24). Angiospermae: Rubus v i t i f o l i u s (from root) (23).  16, 26, 27, 4, with western redcedar  Fungi: Lamprospora trachycarpa (27). Bryophyta: Funaria hygrometrica-protonema. Angiospermae: Rubus v i t i f o l i u s (from root) (27).  28, 15, s o i l samples  Fungi: Patella melaloma (28). Bryophyta: Funaria hygrometrica-protonema. Angiospermae: Rubus v i t i f o l i u s (28).  unburned blocks: 33, 37, 29, 40, with Douglas-fir  Fungi: None. Bryophyta: Mnium insigne, Rhytidiadelphus loreus. Eurhynchium oreganum (dying), Bryum sp., Pohlia bulbifera, Funaria hygrometrica-protonema, Polytrichum .juniperinum, Marchantia polymorpha.  - 167 Pteridophyta: Athyrium filix-femina (37). Herbaceous Angiospermae: Epilobium angustifolium, Epilobium adenocaulon, Galium triflorum, Trientalis l a t i f o l i a , Tiarella t r i f o l i a t a , Viola orbiculata. Woody Angiospermae: Rubus parviflorus (37), Sambucus pubens (40).  41, 38, 35, 30,  Fungi: None. Bryophyta: Rhytidiadelphus loreus (dying), Eurhynchium oreganum (dying), Mnium insigne, Bryum sp., Funaria hygrometrica-protonema, Marcnantia polymorpha, Hypnum circinale. Polytrichum .juniperinum. Pteridophyta: Athyrium filix-femina (38), Polystichum muniturn (30). Herbaceous Angiospermae: Epilobium adenocaulon, Galium triflorum, Senecio vulgaris, Trientalis l a t i f o l i a , Viola orbiculata. Woody Angiospermae: Rubus v i t i f o l i u s . Rubus parviflorus, Betula papyrifera, Vaccinium parviflorum, Sambucus pubens.  36, 31, 42, 39,  Fungi: None. Bryophyta: Rhytidiadelphus loreus (dying), Mnium insigne, Marchantia polymorpha, Bryum sp., Polytrichum .juniperinum, Leptobryum pyriforme, Pohlia bulbifera, Eurhynchium oreganum, Atrichum undulatum. Pteridophyta: prothallia, Athyrium filix-femina. Dryopteris austriaca, Blechnum spicant, and Pteridium aquilinum. Herbaceous Angiospermae: Galium triflorum, Trientalis l a t i f o l i a , Viola orbiculata. Woody Angiospermae: Betula papyrifera, Rubus parviflorus, Rubus v i t i f o l i u s .  34, 32,  Fungi: None. Bryophyta: Plagiothecium undulatum, Rhytidiadelphus loreus, Mnium insigne, Eurhynchium oreganum (dying), Leptobryum pyriforme. Pteridophyta: Polystichum muniturn, Athyrium f i l i x femina. Herbaceous Angiospermae: Senecio silvaticus, Galium triflorum, Tiarella t r i f o l i a t a . Woody Angiospermae: Vaccinium parviflorum.  with western hemlock  with western redcedar  s o i l samples  - 168 Moss site (a)  (b)  (c)  severely burned blocks: 2, 9, 30, 4, with Douglas-fir  Fungi: Patella albospadica, Lamprospora sp. Bryophyta: Funaria hygrometrica-protonema.  8, 1, 27, 6, with western hemlock  Fungi: Patella albospadica. Lamprospora sp. Bryophyta: Funaria hygrometrica-protonema.  28, 11, 10, 5, with western redcedar  Fungi: Patella albospadica, Lamprospora sp. Bryophyta: Funaria hygrometrica-protonema. Marchantia polymorpha. Pteridophyta: prothallia.  7, 3, s o i l samples  Fungi: Myxomycetes (7). Bryophyta: Funaria hygrometrica-protonema.  moderately burned blocks: 15, 22, 38, 37, with Douglas-fir  Fungi: Patella albospadica, Spicaria sp., Lamprospora sp. Bryophyta: Funaria hygrometrica-protonema. Bryum argenteum (15).  14, 16, 29, 18, with western hemlock  Fungi: Patella albospadica, Arcyria cinerea, Lamprospora sp. (18). Bryophyta: Funaria hygrometrica-protonema, Bryum argenteum.  23, 26, 25, 17, with western redcedar  Fungi: Lamprospora sp., Spicaria sp., Cribraria pyriformis (25), Arcyria cinerea (17). Bryophyta: Funaria hygrometrica-protonema.  19, 24, s o i l samples  Fungi: None. Bryophyta: Funaria hygrometrica-protonema.  unburned blocks: 36, 42, 12, 32, with Douglas-fir  Fungi: Arcyria cinerea (36, 12). Bryophyta: Eurhynchium oreganum (dying), Plagiothecium undulatum (dying), Hylocomium splendens, Rhytidiadelphus loreus, Bryum argenteum. Pteridophyta: Pteridium aquilinum, prothallia. Herbaceous Angiospermae: Pyrola asarifolia, Linnaea borealis.  - 169 21, 33, 41, 20,  Fungi: None. Bryophyta: Eurhynchium oreganum (dying), Plagiothecium undulatum. Rhytidiadelphus loreus. Pteridophyta: Pteridium aquilinum, prothallia. Herbaceous Angiospermae: Pyrola asarifolia, Epilobium adenocaulon. Linnaea borealis. Woody Angiospermae: Vaccinium parvifolium (33).  31, 40, 34, 13,  Fungi: None. Bryophyta: Eurhynchium oreganum (dying), Rhytidiadelphus loreus, Plagiothecium undulatum, Scapania bolanderi. protonemata. Pteridophyta: Polystichum munitum (34). Herbaceous Angiospermae: Linnaea borealis (34), Pyrola asarifolia (UOTl Woody Angiospermae: Vaccinium parvifolium. V. alaskaense (13).  39, 35,  Fungi: None. Bryophyta: Eurhynchium oreganum (dying), Hylocomium splendens. Pteridophyta: None. Herbaceous Angiospermae: Senecio silvaticus (39). Woody Angiospermae: Vaccinium parvifolium (39).  with western hemlock  with western redcedar  s o i l samples  Salal site severely burned blocks:  2, 5, 1, 9,  Fungi: Myxomycetes. Lamprospora sp. (2, 5). Bryophyta: Funaria hygrometrica-protonema.  4, 3, 7, 13,  Fungi: Lamprospora sp. (4). Bryophyta: Funaria hygrometrica-protonema.  10, 14, 11, 8,  Fungi: Spicaria sp. (14). Bryophyta: Funaria hygrometrica-protonema.  12, 6,  Fungi: None. Bryophyta: Funaria hygrometrica-protonema.  with Douglas-fir with western hemlock  with western redcedar s o i l samples  moderately burned blocks:  20, 23, 27, 18, with Douglas-fir  Fungi: Arcyria cinerea, Lamprospora sp., Myxomycetes. Patella melaloma (18). Bryophyta: Funaria hygrometrica-protonema. Pteridophyta: prothallia.  - 170 Angiospermae;  22, 17, 25, 16,  Fungi; Spicaria sp., Arcyria cinerea (25), Inocybe sp. (17). Bryophyta; Funaria hygrometrica-protonema. Pteridophyta: prothallia. Woody Angiospermae: Gaultheria shallon (16).  26, 28, 19, 21, with western redcedar  Fungi: Arcyria cinerea (26, 28), Spicaria sp. (26). Bryophyta: Funaria hygrometrica-protonema. Pteridophyta: prothallia. Woody Angiospermae: Gaultheria shallon (21).  24, 15,  Fungi: Inocybe sp. (24), Patella melaloma (15). Bryophyta: Funaria hygrometrica-protonema. Pteridophyta; prothallia. Woody Angiospermae: Gaultheria shallon (24).  with western hemlock  s o i l samples  (c)  Senecio vulgaris (18).  unburned blocks:  29, 37, 36, 30,  Fungi; None. Bryophyta; Eurhynchium oreganum (dying), Rhytidiadelphus triquetrus, Funaria hygrometrica-protonema . Pteridophyta: Pteridium aquilinum. prothallia. Herbaceous Angiospermae; Epilobium adenocaulon (30), Hypochaeris radicata (36). Woody Angiospermae: Gaultheria shallon (29, 36).  31, 35, 38, 41,  Fungi: None. Bryophyta: Eurhynchium oreganum (dying), Hylocomium splendens, Funaria hygrometrica-protonema. Pteridophyta: Pteridium aquilinum, prothallia. Woody Angiospermae; Holodiscus discolor (35), Gaultheria shallon, Betula papyrifera (35).  33, 32, 39, 34,  Fungi: None. Bryophyta: Eurhynchium oreganum (dying), Rhytidiadelphus loreus, Leptobryum pyriforme. Bryum cespitosum (39). Pteridophyta: Pteridium aquilinum, prothallia. Herbaceous Angiospermae; Viola orbiculata (34). Woody Angiospermae: Gaultheria shallon.  42, 40,  Fungi: None. Bryophyta: Eurhynchium oreganum (dying), Parmelia vittata (40). Pteridophyta: prothallia. Woody Angiospermae: Gaultheria shallon.  with Douglas-fir  with western hemlock  with western redcedar  s o i l samples  - 171 3. Vegetation on July 15, I960 Swordfern site (a)  severely burned blocks:  1, 5, 11, 13,  Bryophyta: Funaria hygrometrica well developed, Pohlia bulbifera, Bryum argenteum. Pteridophyta: Equisetum arvense. Woody Angiospermae: Populus trichocarpa.  3, 12, 19, 10,  Bryophyta: Funaria hygrometrica well developed, Pohlia bulbifera, Bryum argenteum. Herbaceous Angiospermae: Senecio vulgaris.  with western redcedar  7, 14, 21, 6,  Bryophyta: Funaria hygrometrica, Pohlia bulbifera, Bryum argenteum. Herbaceous Angiospermae: Senecio vulgaris (14). Woody Angiospermae: Salix scouleriana (6).  2, 20,  Bryophyta:  with Douglas-fir  with western hemlock  Funaria hygrometrica, Bryum argenteum.  s o i l samples  (b)  moderately burned blocks: 18, 22, 8, 17, with Douglas-fir  Fungi: Agaricus sp. (17). Bryophyta: Funaria hygrometrica, Bryum argenteum. Pteridophyta: Equisetum arvense (8).  24, 23, 25, 9,  Fungi: Peziza sp. (23). Bryophyta: Funaria hygrometrica, Bryum argenteum. Marchantia polymorpha (25)» Pteridophyta: Equisetum arvense (9), Epilobium adenocaulon (25). Woody Angiospermae: Populus trichocarpa (24).  16, 26, 27, 4,  Fungi: Peziza sp. (27). Bryophyta: Funaria hygrometrica, Bryum argenteum, Mnium insigne (4). Woody Angiospermae: Populus trichocarpa (16).  28, 15, s o i l samples  Bryophyta:  with western hemlock  with western redcedar  (c)  unburned blocks:  33, 37, 29, 40,  with Douglas-fir  No change.  Funaria hygrometrica. Bryum argenteum.  - 172  with western hemlock  41, 38, 35, 30,  Bryophyta; Pogonatum alpinum, Pohlia bulbifera, Bryum sp» Pteridophyta; Pteridium aquilinum (38), Blechnum spicant (30).  36, 31, 42, 39,  No change.  34, 32,  No change.  with western redcedar s o i l samples  Moss site (a)  severely burned blocks: Fungi: Peziza sp. (2). Bryophyta; Pohlia bulbifera (2), Marchantia polymorpha (9). Herbaceous Angiospermae; Senecio vulgaris (30). Woody Angiospermae; Alnus rubra.  2, 9, 30, 4, with Douglas-fir  8, 1, 27, 6, with western hemlock 28, 11, 10, 5, with western redcedar 7, 3, s o i l samples (b)  y  Bryophyta:  Bryophyta:  Funaria hygrometrica, Riccardia sp.  (8).  Funaria hygrometrica, Pohlia bulbifera.  Herbaceous Angiospermae:  Senecio vulgaris.  moderately burned blocks:  15, 22, 38, 37,  with Douglas-fir  Bryophyta:  (38).  Funaria hygrometrica. Pohlia bulbifera  Herbaceous Angiospermae;  Pyrola asarifolia (37)•  14, 16, 29, 18,  Bryophyta: Pohlia elongata, P. bulbifera, Funaria hygrometrica. Herbaceous Angiospermae: Pyrola asarifolia (14).  with western redcedar  23, 26, 25, 17,  Fungi: Peziza sp. (25). Bryophyta: Funaria hygrometrica. Herbaceous Angiospermae: Senecio vulgaris (26).  19, 24,  Bryophyta:  with western hemlock  s o i l samples  Bryum argenteum,. Funaria hygrometrica.  - 173 unburned blocks:  36, 42, 12, 32,  Bryophyta; Polytrichum .juniperinum, Funaria hygrometrica, Leptobryum pyriforme• Woody Angiospermae; Rubus v i t i f o l i u s (from rhizome)  21, 33, 41, 20, with western hemlock  No change.  31, 40, 34, 13, with western redcedar  Bryophyta: Leptobryum pyriforme, Bryum argenteum, Funaria hygrometrica. Pteridophyta: Pteridium aquilinum. Herbaceous Angiospermae: Senecio vulgaris.  39, 35,  No change.  with Douglas-fir  s o i l blocks Salal site severely burned blocks:  2, 5, 1, 9,  Bryophyta:  Funaria hygrometrica.  4, 3, 7, 13, with western hemlock  Bryophyta: Funaria hygrometrica, Aulacomnium androgynum (3).  10, 14, 11, 8,  Bryophyta: Funaria hygrometrica. Woody Angiospermae; Salix scouleriana.  with Douglas-fir  with western redcedar 12, 6, s o i l samples  Herbaceous Angiospermae;  Senecio vulgaris.  moderately burned blocks: 20, 23, 27, 18, with Douglas-fir  Herbaceous Angiospermae:  22, 17, 25, 16, with western hemlock  No change.  26, 28, 19, 21, with western redcedar  Herbaceous Angiospermae:  Senecio vulgaris (18).  Salix scouleriana (19).  - 174 No change.  24, 15,  s o i l samples  (c)  unburned blocks:  29, 37, 36, 30,  Bryophyta: Pohlia bulbifera, Funaria hygrometrica. Herbaceous Angiospeniiae: Senecio vulgaris (29).  31, 35, 38, 41,  Bryophyta: Atrichum undulatum (31), Funaria hygrometrica, Polytrichum .juniperinum (41).  with western redcedar  33, 32, 39, 34,  Bryophyta: Funaria hygrometrica, Polytrichum .juniperinum, Marchantia polymorpha (34). Herbaceous Angiospermae: Fragaria glauca (39).  42, 40,  No change.  with Douglas-fir with western hemlock  s o i l samples  4- Fungi of genus Boletus on November 25, I960 Swordfern site (a)  severely burned blocks: 1 3, 12 14 20, 2  (b)  -  with with with soil  Douglas-fir western hemlock western redcedar samples  moderately burned blocks: 25, 24 - with western hemlock Moss site  (a)  severely burned blocks: 4 - with Douglas-fir 1 - with western hemlock 11 - with western redcedar Salal site  (a)  severely burned blocks: 13 - with western hemlock  Fungi of the Eumycetes on sample block December 5, I960 Swordfern site severely burned blocks: l  21, 6 - with western redcedar moderately burned blocks: 8 - with Douglas-fir Moss site severely burned blocks: 2, 30 - with Douglas-fir 6 - with western hemlock 7 - s o i l sample moderately burned blocks: 22, 37 - with Douglas-fir 19 - s o i l sample unburned blocks: 41 - with western hemlock 31, 34 - with western redcedar 35 - s o i l sample Salal site severely burned blocks: 9 - with Douglas-fir 4 - with western hemlock unburned blocks: 35 - with western hemlock 32 - with western redcedar 40, 42 - s o i l blocks  - 176 6. Vegetation on December 15, I960. Only the changes i n plant cover from July 15 are noted. Swordfern site (a)  severely burned blocks:  1, 5, 11, 13,  Fungi  3, 12, 19, 10,  Fungi: Thelephora sp., Polyporus variegatus, Agaricus sp.  7, 14, 21, 6,  No change.  2, 20,  Fungi:  with Douglas-fir  with western hemlock  Polyporus variegatus, Agaricus sp., Thelephora sp. Bryophyta: Polytrichum .juniperinum, Bryum sp. Herbaceous Angiospermae: Viola orbiculata.  with western redcedar  Thelephora sp.  s o i l samples  (b)  (c)  moderately burned blocks: 18, 22, 8, 17, with Douglas-fir  Fungi: Agaricus sp., Thelephora sp., Polyporus variegatus. Herbaceous Angiospermae: Epilobium adenocaulon.  24, 23, 25, 9, with western hemlock  Fungi: Agaricus sp., Thelephora sp. Herbaceous Angiospermae: Galium triflorum.  16, 26, 27, 4, with western redcedar  Fungi:  Agaricus sp.  28, 15, s o i l samples  Fungi:  Agaricus sp.  unburned blocks:  33, 37, 29, 40, with Douglas-fir  Fungi: Craterellus sp. Bryophyta: Hylocomium splendens. Pteridophyta: Blechnum spicant.  41, 38, 35, 30,  Fungi: Thelephora sp. Bryophyta: Atrichum undulatum.  with western hemlock  - 177 36, 31, 42, 39,  No change.  34, 32,  Fungi:  with western redcedar  Thelephora sp.  soil samples Moss site  (a)  severely burned blocks:  2, 9, 30, 4,  Fungi:  Thelephora sp.  8, 1, 27, 6,  Fungi: Thelephora sp., Agaricus sp. Pteridophyta: Equisetum arvense.  with Douglas-fir with western hemlock 28,  11, 10, 5,  Fungi:  Agaricus sp.  with western redcedar  No change.  7, 3,  s o i l samples  (b)  moderately burned blocks:  15, 22, 38, 37,  with Douglas-fir 14, 16,  29, 18,  Fungi: Thelephora sp. Bryophyta: Eurhynchium oreganum. Pteridophyta: Dryopteris austriaca. Fungi:  Thelephora sp.  with western hemlock  23, 26, 25, 17,  No change.  19, 24,  Fungi:  with western redcedar  Thelephora sp., Agaricus sp.  s o i l blocks  (c)  unburned blocks:  36, 42, 12, 32,  with Douglas-fir  Pteridophyta: spicant.  Dryopteris austriaca, Blechnum  - 178  with western hemlock  21, 33, 41, 20,  Fungi; Thelephora sp. Bryophyta: Pohlia bulbifera, Leptobryum pyriforme. Pteridophyta: Blechnum spicant.  31, 40, 34, 13,  No change.  39, 35,  No change.  with western redcedar s o i l samples  Salal site (a)  severely burned blocks:  2, 5, 1, 9,  with Douglas-fir  Fungi: Agaricus sp. Bryophyta: Eurhynchium oreganum. Woody Angiospermae: Gaultheria shallon.  4, 3, 7, 13,  No change.  10, 14, 11, 8,  No change.  12, 6,  Fungi: Thelephora sp., Agaricus sp. Bryophyta: Funaria hygrometrica, Bryum argenteum.  with western hemlock with western redcedar s o i l samples  (b)  moderately burned blocks:  20, 23, 27, 18, with Douglas-fir  Fungi: Thelephora sp., Agaricus sp. Bryophyta: Bryum argenteum. Pteridophyta: Dryopteris austriaca.  22, 17, 25, 16,  Fungi: Thelephora sp. Bryophyta: Bryum argenteum.  26, 28, 19, 21, with western redcedar  No change.  24, 15,  Fungi: Agaricus sp. Bryophyta: Funaria hygrometrica. Pteridophyta: Dryopteris austriaca.  with western hemlock  s o i l samples  (c)  unburned blocks: with Douglas-fir  29, 37, 36, 30,  Bryophyta: Bryum argenteum. Pteridophyta: Blechnum spicant, Dryopteris austriaca, Athyrium filix-femina.  31, 35, 38, 41,  Bryophyta:  33, 32, 39, 34,  Fungi:  42, 40,  Fungi: Thelephora sp., Agaricus sp. Bryophyta: Leptobryum pyriforme•  Bryum argenteum.  with western hemlock  Agaricus sp.  with western redcedar s o i l samples  7. Fungi on February 10, 1961 Swordfern site (a)  severely burned blocks:  5, H - with Douglas-fir 1, 11 - with Douglas-fir 9, 10, 19 - with western hemlock n 3, 12 n it 10 " redcedar 6, 7, 14 11  11  11  11  (b)  —  Stereum sp.  moderately burned blocks: 18, 17, 8 -with 18 - with 8 - with 17 - with 9, 23, 24, 25 - with 4, 27 -with  (c)  sp. - Stereum Polyporus cinnamomeus -- Stereum sp. cinnamomeus -— Polyporus Patella gilva  _ Douglas-fir Douglas-fir Douglas-fir Douglas-fir western hemlock western redcedar —  -  --  Stereum sp. Craterellus sp. Polyporus cinnamomeus Humarina rufa Stereum sp. Stereum sp.  unburned blocks :  29 - with Douglas-fir 38 -with western hemlock  1  -  Craterellus sp. Craterellus sp.  Polyporus perennis is reported commonly on burned-over s o i l ; these specimens seem to f i t into. P. cinnamomeus best, however.  Moss site severely burned blocks: 2 2, 4, 9, 30 6 5 -  with with with with  Douglas-fir Douglas-fir western hemlock western redcedar  -  Stereum sp Galera sp. Inocybe sp Galera sp.  -  Stereum sp Stereum sp Stereum sp Galera sp.  moderately burned blocks: 22 16 17, 25,26 23  -  with with with with  Douglas-fir western hemlock western redcedar western redcedar  Salal site severely burned blocks: B, 11, 14 - with western redcedar - Galera sp. 12 - s o i l sample - Galera sp. unburned blocks: 41 - with western hemlock 40 - s o i l sample  - Galera sp. - Galera sp.  - 181 APPENDIX IV Methods of Soil Chemical Analysis Determination of pH pH measurements were taken on material finer than two mm. using a Beckman pH meter, Model N, i n a paste-like soil-water mixture. Determination of Organic Matter Reagents  1 N potassium dichromate. Dissolve 49.04 gm. of reagent grade  K^Cr^Oj  i n water and dilute to 1 l i t e r .  0.5 ferrous sulfate. Dissolve 140 gm. of reagent grade FeSO/fB^O i n water, add 40 ml. concentrated HgSO,, cool, and dilute to 1 l i t e r . Standardize this reagent each day by titrating against 10 ml. of N potassium dichromate, as directed i n the method given below. - Barium diphenylaminesulfonate. solution.  Prepare a 0.16 per cent aqueous  - 0-phenanthroline ferrous complex (optional).  Prepare 0.025 M solution of one of the phenanthroline ferrous complex indicators.  - Sulfuric acid; not less than 96 per cent. - Phosphoric acid; 85 per cent, U.S.P. grade. Procedure Transfer a weighed quantity of s o i l (ground to pass a 0.5 mm. sieve) containing 10 to 25 mg. of organic carbon into a 500 ml. Erlenmeyer flask, and add 10 ml. of N potassium dichromate. Then add rapidly 20 ml. of concentrated sulfuric acid, directing the stream into the solution. Immediately swirl vigorously by hand for 1 minute and let the flask stand on a sheet of asbestos for about 30 minutes. Then add 20 ml. of water, and 0.5 ml. of phenanthroline ferrous complex indicator. Proceed with the titration as follows: add the ferrous sulphate solution u n t i l the solution i s purple or blue, then add the ferrous sulphate i n small lots of about 0.5 ml. u n t i l the color flashes to green with l i t t l e or no warning. Add 0.5 ml. of N potassium dichromate to restore an excess of  - 182 dichromate and complete the titration by adding ferrous sulphate drop by drop to a light green end point. If more than 8 ml. of the available 10 ml. of potassium dichromate i s reduced, the determination should be repeated with less s o i l . Percentage of organic matter i n s o i l sample  =  ( M i l l i l i t e r s of 1 M ( K g C r ^ ) reduced) x 0.69 Weight of sample (gm) References Peech, M. et a l . Methods of s o i l analysis for s o i l f e r t i l i t y investigations. U.S.D.A. circular No. 757. Determination of exchangeable cations and exchange capacity of soils - rapid micro methods u t i l i z i n g centrifuge  and spectrophotometer. Soil Sc. 59:25-37. 1945.  Cheng, K. L . et a l . Removing interfering metals i n the versenate determination of calcium and magnesium. Soil Sc. 75:37-40.  1953.  Busworth Chemical Company Technical Bulletin No. 2, The Versenes. Busworth Chemical Company, Feamingham, Mass. Mitchell. Spectrographic analysis of soils and plants. Macauly Institute for S o i l Res. Commonwealth Bureau of Soil Sc. Tech. Comm. No. 44. Ch. 4.  Determination of Exchangeable Cations and Exchange Capacity Extraction Reagents Ammonium acetate 1 N, pH 7.0 - Prepare sufficient volume by mixing 70 ml. Nh OH, sp. gr. 0.90, and 58 ml. of 99.5$ HA per l i t e r of solution desired. After cooling adjust to pH 7.0 and dilute with water to volume. HC1 concentrated. HNO^ concentrated. 1:1 HC1 1 part cone. HC1 to part H0H.  - 183 1:1 &2®2  P  a r t  r e a  g  e n t  grade HgOg, 30% and 1 part HgO.  L i (Internal Standard) 1250 gamma/ml.  (see below).  Apparatus 400 ml. beakers Filtrators Buchner funnels, 70 cm. Whatman 42 f i l t e r paper, 7.0 cm. Graduate cylinders, 100 ml. 250 ml. Procedure Place 20 gm. of s o i l i n a 100 ml. beaker, add 50 ml. NH.Ac. Stopper flask, shake for several minutes and allow to stand overnight. Transfer the s o i l to a small buchner funnel fitted to a f i l t r a t o r and f i l t e r the solution into a 400 ml. beaker. Leach the sample with an additional 150 ml. NH.Ac using gentle suction (take about g hour) to complete leaching. dryness.  Place the f i l t r a t e on a steam bath or hot plate and evaporate to Keep beaker covered.  Add 5 ml. concentrated HN0„ and 1 ml. concentrated HC1 and evaporate to dryness. Add 5 ml. 1:1 ^ O ^ to destroy organic matter (add more i f necessary) and heat gently to avoid spattering. Add 5 ml. 1:1 HC1 and evaporate to dryness to dehydrate s i l i c a . Take up the residue with 2 ml. concentrated HC1, policing any adhering residue. F i l t e r into a 250 ml. volumetric flask and add 5 ml. of a 1250 gamma L i / m l . solution and make to volume. Designate this solution ' A ' . NOTE:  If care i s used i n taking aliquots from solution A, i t may not be necessary to remove the siliceous residue by f i l t e r i n g .  Determination of Exchange Capacity Reagents 95$ ethyl alcohol, U.S.P. Sodium chloride Antifoam spray NaOH 1 N Technical Standard 0.2 N H S0. 2 4 o  Standard 0.1 N HaOH (C0 free) 2  Methyl red indicator Apparatus 400 ml. beaker 100 ml. graduate, 25 ml. graduate 600 ml. Kjeldahl flasks Kjeldahl d i s t i l l a t i o n apparatus 2-50 ml. burettes (1 base burette) 500 ml. Erlenmeyer flask Procedure Leach the s o i l sample from step 1 with 80 ml. ethyl alcohol i n small portions to remove excess acetate. Transfer s o i l with the f i l t e r paper to a Kjeldahl flask; add 400 ml. HgO, about 10 gm. NaCl and a spray of the antifoam agent. Add 25 ml. of 1 N NaOH and connect immediately to the d i s t i l l a t i o n apparatus. D i s t i l l about 150 ml. into a flask containing 50 ml. 0.2 N H^SO^ and methyl red. If the indicator i n the acid starts to turn yellow immediately, add 10-20 more HJ50..  Titrate the excess acid with the 0.1 N NaOH. Calculate exchange capacity and express as m.e. per 100 gm. s o i l .  Determination of Exchangeable Cations Calcium Reagents (1) Stock lithium internal standard - 12,500 gamma L i / m l . Dissolve 7,6377 g. L i C l i n l . L . (Dilute 1:10 to give 1250 gamma L i / m l . ) . (2) Stock calcium standard - 1250 gamma Ca/ml. Place 3.1215 g. reagent grade CaC0„ i n a l . L . flask. Add sufficient HC1 to dissolve the CaC0_ and add sufficient excess to make the solution 0.1 N i n HC1 (12.5 ml. cone. HC1 for l . L . std.). After the carbonate has dissolved make to l . L . (3) Flame photometer standards for Ca. Prepare a series of standards containing 0, 50, 100, 150 and 200 gamma. Ca/ml. and containing 25 gamma L i / m l . (4)  L i internal standard, 25 gamma L i / m l . This solution i s to be used for diluting samples high i n Ca and should be prepared exactly from the same L i stock solution used for the flame photometer standard.  Apparatus Volumetric flasks, 500 ml. and 250 ml. 25 ml. Erlenmeyer flasks. Perkin Elmer flame photometer. Procedure Determine the calcium concentration of the samples as directed in the flame photometer manual. If the concentration i s too high, dilute the sample with the 25 gamma L i / m l . solution.  - 186 Potassium Reagents (1) Lithium internal standard solutions - as above. (2) Stock potassium standard, 1250 gamma K/ml. Dissolve 2.3836 gm. KCl per l i t e r of solution. (3) Flame photometer standards for K. Prepare a series of standards containing 0, 10, 20, 30, 40 and 50 gamma K/ml. and 25 gamma L i / m l . As before, prepare twice the volume of the 0 and the highest standard. Apparatus As above. Procedure As above. Magnesium and Calcium Reagents (1) Standard MgCl 0.2 N. 2  Place 4.2165 g. MgCO^ i n a 500 ml. volumetric  flask. Add 10 ml. of HC1 to dissolve the carbonate and add 15 ml. l/N NaOH to make the solution nearly neutral. (2) Standard MgCl 0.02 N. 2  Dilute the 0.2 N MgCl solution 1:10. 2  (3) Standard EDTA. Dissolve di-disodium dehydrogen tetra-acetic acid (Versenate) i n 2 l i t e r s (approx.) of H 0. Add about 35 drops 0.1 N MgCl to make for a sharp end point. 2  2  (4) Eriochrome black T. indicator. Prepare a solution of 1 g. of hydroxydamine hydrochloride i n 25 ml. ethyl alcohol. Prepare the indicator as needed by adding 0.2 g. of eriochrome black T (1 - hydroxy - 2 - naphthylazo - 5 - nitro - 2 - naphthol - 4 sulphonic acid sodium salt) and 5 ml. of this solution. (5) NH.C1 - NH.OH buffer solution. Dissolve 67.5 g . of NH.CI i n 200 ml. it k 4 of water and mix with 570 ml. of cone. NH,OH. Dilute to l . L . The pH should be 10. k  - 187 Apparatus 125 ml. Erlenmeyer flasks. 50 ml. burette. Procedure Pippette a 5 ml. aliquot of solution A into a 125 ml. Erlenmeyer flask. Add sufficient water to make the volume approximately 40 ml. Place an additional 7 ml. of buffer i n the solution; add 2-4 drops of the eriochrome black T indicator and titrate the solution until a clear blue end point i s reached.  Absorbed Phosphorus Reagents Ammonium floride - I N (approx.). Keep i n plastic bottle.  Dilute 37 g. NH.F/liter.  0.5 N HC1 - (approx.) 20.2 ml. cone. HCl/500 ml. Extracting solution - 0.03/N NH.F - 0.025 N HC1 30 ml. IN NH^F + 50 ml. 0.5 N H C l / l i t e r . P.B. - Ammonium molybdate - HC1 reagent, boric acid saturated: Dissolve 100 g. reagent grade ammonium molybdate i n 850 ml. HgO. F i l t e r and cool. Make solution of 1700 ml. cone. HC1 i n 160 ml. HJD. Cool. Add f i r s t solution to second slowly with constant stirring. Add approx. 110 g. reagent grade boric acid and dissolve. P.C. - Amino naphtol sulphonic acid: 2.5 g. of 1 part amino 2 parts naphtol and 4 parts sulphonic acid, 5.0 g. sodium sulfite (Na^O^). 146.25 g. sodium bisulfite (meta Na^gO,.); Mix ingredients and grind to fine powder i n mortar. For usi dissolve 16 g. of powder in 100 ml. warm E^O. Add 2 g. reagent grade o ° o , f i l t e r and allow to stand overnight. Store i n dark glass ana. renew every two weeks. H  B  P standard - 100 ppm.: 0.4393 g. pure KH P0,/liter H„0 containing 100 ml. IN HC1. Prepare 10 - 20 - 30 - 40 - 50 ppm. standard solution by diluting the 100 ppm. standard solution with extracting solution. 2  Procedure Extract - Shake 5 g. s o i l into 125 ml. Erlenmeyer flask with 50 ml. extracting solution for one minute, and f i l t e r . Take 5 ml. unknown solution + 5 ml. H^O + ^ ml. P.B. + \ ml. P.C. and read with photoelectronic colorimeter i n 30 minutes. Use 660 f i l t e r . References Bray, Roger H. and L . T. Kurtz.  1945. Soil Sc. 99:39-45.  Jackson, M. L . 1958. Soil Chemical Analysis, p.148-151. Prentice - Hall, INC. Englewood C l i f f s , N. J .  Nitrogen Determination Weigh out five g. of s o i l and transfer using folded f i l t e r paper to an 800 ml. Kjeldahl flask. Add approximately 30 - 40 ml. cone. H^SO,, 10 g. ( l tsp.) of a mixture of 10 parts anhydrous Na S0. and 1 part CuSO./SiHgO. Mix ingredients by swirling the flask. Ada 2 - 3 selenized granules. o  Digest u n t i l the solution i s clear and continue digestion for twenty minutes. Cool and then add gradually 300 ml. of tap HgO. Shake well. Cool again. Now add about 1 teaspoonful of glass beads and/or .5 g. of granulated Zn and an excess (90 ml.) of cone. NaOH solution (40$), pouring down the side of the flask to prevent mixing of solutions and loss of NH„. Connect to the d i s t i l l i n g apparatus immediately and then swirl the flask gently to mix the contents. D i s t i l l into a 300 ml. Erlenmeyer flask containing 25-50 ml. of saturated boric acid solution, measured with a graduate (50 ml. of boric acid takes care of 95 mg. of N as N£L). Also add 4 drops of a mixed indicator of bromocresol green and methyl red. The tube from the d i s t i l l i n g apparatus must extend below the surface of the acid to prevent loss of NH^. Collect approximately 150 ml. of the d i s t i l l a t e and titrate the boric acid on the complex with standard N/l4 H^SO.. A blank should be run in every case as there i s a slight correction. Subtract the blank from the total amount of acid required for the sample. ml. of acid x normality x .014 .  , ,  „  -,^ at™ X  1 U U — X>i\l  weight of sample where .014 represents the gms. N per ml. i n a normal solution.  - 189 Where the normality i s N/14 the equation becomes ml. of acid x N/l4 X .014 ~ .^ n o a™ r — x 100 = ml. of acid x .02 - %N j g. n  t  3  3  If a 1 g. sample i s used, say of a l f a l f a , the calculation simplifies to ml. of acid 0 . 1 = #N. Mixed Indicator Mix 10 ml. of 0 . 1 per cent bromocresol green i n 95 per cent alcohol with 2 ml. of 0 . 1 per cent methyl red in 95 per cent alcohol. The color produced by this indicator in boric acid i s bluish green. Titrate with standard acid u n t i l the blue color just disappears. One drop i n excess w i l l turn the solution pink. If titrated to a faint pink, subtract 0 . 0 2 ml. from the reading. References Indus and Eng. Chem.  12:350-2. 1920.  Soil Sc. 5 9 : 4 7 - 5 2 . 1 9 4 5 .  - 190 APPENDIX V Plates Coloured Photographs - by V. J . Krajina Plate I - by J . Soos Plate XVII - XX - by 0. Horvath  I.  II.  III.  IV.  V.  VI.  Ditches for sample block collection: upper row - Swordfern site; center row - Moss site; lower row - Salal s i t e . Unburned sample blocks i n the greenhouse, March, I960: from l e f t to right - Salal site, Moss site, Swordfern site. Salal site with dying Plagiothecium moss and surviving ferns and dicotyledons. Burning process i n the Metallurgical Laboratory, March - A p r i l , I960: Measuring of temperature on potentiometer with multiple pole switch gear for six outlets leading from the burned sample block. The sample block during burning, insulated with metallurgical bricks and asbestos sheets, equipped with two thermocouple junctions on the block surface i n ceramic sleeves; and with four junctions at depths of two and four inches, driven into the block through the holes of the front wall of the can. Note the gas burner over the block and the oxygen regulator fan i n the upper right corner. Burned surface of Swordfern site samples: 3 - severely burned sample with ash was used for hemlock; 26 - moderately burned sample with slightly scorched mineral surface was used for redcedar. Burned surface of Moss site samples: 9 - severely burned sample with ash was used for Douglas-fir; 29 - moderately burned sample with charcoal, ash and coke was used for hemlock. Burned surface of a Swordfern site group with ash and scorched mineral s o i l . Aggregates on mineral s o i l and from organic remains:  - 191  a - scorched mineral b - same on the Moss c - coke formed from Scale about half VII.  VIII.  clods on the Swordfern site; site; the organic matter of the Moss site. size.  Burned surface of Salal site samples: 11 - severely burned sample with ash used for redcedar; 6 - sample with charcoal and charred wood used for s o i l analyses; 28 - moderately burned sample with charcoal and ash; 26 - sample with charred wood both used for redcedar. Four-week-old Douglas-fir seedlings before thinning: 5 - severely burned Swordfern site sample; 36 - unburned control Salal site sample. Note the equally developed seedlings and the greater density on the f i r s t picture.  IX.  Six-week-old Douglas-fir seedlings after thinning to five: 29 - unburned control Swordfern site sample; 1 - severely burned Salal site sample. Note the equally developed seedlings regardless of surface differences.  X.  Four-week-old western hemlock seedlings on severely burned samples before thinning: 19 - Swordfern site sample; 1 - Moss site sample; 3 - Salal site sample. Note the equally developed seedlings on the three different seedbeds. Mineral aggregates are shown on the Swordfern block; mineral aggregates and coke on the Moss block and charred wood with charcoal on the Salal block.  XI.  Six-week-old western hemlock seedlings on unburned control samples before thinning: 30 - Swordfern site sample; 33 - Moss site sample. Note the equally developed seedlings and the different cover of the surface.  XII.  Six-week-old western redcedar seedlings before thinning on severely burned samples: 21 - Swordfern site sample; 11 - Salal site sample, with ten transplanted germinants.  - 192 Note the scorched mineral s o i l on the f i r s t and the charcoal and coke on the second blockj the latter with fewer but larger original seedlings. XIII.  Cross-section of severely burned analyzed sample blocks: 20 - Swordfern site sample; 7 - Moss site sample. Note the remains of old charcoal under the surface and the grey eluviated spots (Ae) on the right side of the Moss site block.  XIV.  Cross-section of moderately burned sample blocks: 15 - Swordfern site sample (analyzed); 24 - Moss site sample (reserve). Note the old and new charcoal and the compactness in the Moss block.  XV.  Cross-section of unburned control analyzed sample blocks: 34 - Swordfern site sample; 39 - Moss site sample. Note the humic layer (Ah) in Swordfern block and the charcoal layer underlain with eluviated traces (Ae) i n the Moss block.  XVI.  Cross-section of analyzed Salal site sample blocks: 6 - severely burned sample; 42 - unburned control sample. Note the loss i n thickness from burning on the upper block and the vegetation with loose humus i n the lower block. Some mineral constituent i s also apparent i n the upper horizon.  XVII.  XVIII.  One-season-old seedlings from the experiment and from the sample areas at Haney: Upper row - Douglas-fir: A, moderately burned Swordfern sample (17); B, Haney - Moss site plot; C, Haney Swordfern site plot. Center row - western hemlock: D, unburned control Swordfern site sample (30, 35, 41); E , Haney - Swordfern site plot. Lower row - western redcedar: F, five-week-old plants from a l l three sites and a l l three treatments; G, Haney - Swordfern site plot; H, severely burned Salal site samples (8, 10); J , severely burned Swordfern site sample ( l ) . Swordfern site samples with average growth of seedlings from each group at the end of stimulated early growth (April 7, 1961). Arrangement from l e f t to right - moderately burned, unburned control, severely burned. Scale i n centimetres.  - 193 XIX.  Moss site samples with average growth of seedlings from each group at the end of stimulated early growth (April 7, 1961). Arrangement from left to right - moderately burned, unburned control, severely burned. Scale i n centimetres.  XX.  Salal site samples with average growth of seedlings from each group at the end of stimulated early growth (April 7, 196l). Arrangement from left to right - moderately burned, unburned control, severely burned. Scale i n centimetres.  XXI.  Part of the experimental lay-out showing Douglas-fir and hemlock seedlings on the Swordfern site at right. Note the smallest seedlings of both species i n the middle groups of unburned control blocks. In the middle of the picture the pale colour of hemlock i s noticeable on the moderately burned Swordfern  blocks (June 22, 1961).  40 - close-up of the unburned Swordfern sample with three chlorotic Douglas-fir seedlings. XXII.  XXIII.  2 - chlorotic Douglas-fir seedlings from the severely burned Moss site sample, from the group with lowest productivity on the Moss site (June 30, 196l). 11 - purple-tinted western redcedar seedlings from the severely burned Salal site sample: 39 - unburned control Swordfern site sample. Both groups produced the lowest production i n their sites (June 30, 1961). The moss i s Funaria hygrometrica.  XXIV.  11 - chlorotic western redcedar seedlings suffering from nutritional deficiency on the severely burned Moss site sample: 36 - unburned Swordfern site sample. Both are from the groups of lowest production. Note the purple discoloration of the seedling stems on the f i r s t picture  (June 30, 1961).  XXV.  Swordfern site. Two blocks from each treatment with Douglas-fir in the upper row; western hemlock i n the centre and western redcedar at the bottom. The arrangement from l e f t to right moderately burned, unburned control, severely burned. Scale  i n centimetres (June 30, 196l).  XXVI.  Moss site. Two blocks from each treatment with Douglas-fir i n the upper row; western hemlock i n the centre and western redcedar  - 194 at the bottom. The arrangement from left to right - moderately burned, unburned control, severely burned. Scale i n centi-  metres. XXVII.  (June 30, 196l).  Salal site. Two blocks from each treatment with Douglas-fir i n the upper row; western hemlock i n the centre and western redcedar at the bottom. The arrangement from l e f t to right - moderately burned, unburned control, severely burned. Scale i n centi-  metres.  (June 30, 1961).  XXVIII.  Severely burned sample blocks. Two blocks from each site with Douglas-fir i n the upper row; western hemlock i n the centre and western redcedar at the bottom. The arrangement by site from l e f t to right - Salal site, Moss site, Swordfern site. Note the increase of height from Salal to Swordfern site. Scale i n decimetres. (June 30, 196l).  XXIX.  Moderately burned sample blocks. Two blocks from each site with Douglas-fir i n the upper row; western hemlock i n the centre and western redcedar at the bottom. The arrangement by site from l e f t to right - Salal site, Moss site, Swordfern site. Note the general uniformity of height for a l l sites. Scale  in decimetres.  XXX.  (June 30, 196l).  Unburned control sample blocks. Two blocks from each site with Douglas-fir i n the upper row; western hemlock i n the centre and western redcedar at the bottom. The arrangement by site from l e f t to right - Salal site, Moss site, Swordfern site. Note the sequence from the highest growth with Moss site and lowest with Swordfern site for a l l three species. Scale i n  decimetres.  (June 30, 196l).  II  VI  A  B  C  VII  IX  —  pi  IS —  ^  M i  aft  R^> .-'SB  1  . :  I  XVI  XVII  XVIII  XX  XXVI  XXVII  XXVIII  XXIX  xxx  

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