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Juvenile - mature wood transition in second-growth coastal Douglas-fir 1987

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JUVENILE - MATURE WOOD TRANSITION IN SECOND-GROWTH COASTAL DOUGLAS-FIR By CARLOS MARIO DI LUCCA Eng., U n i v e r s i d a d Nacional de La P l a t a , 1978 THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF THE FACULTY OF GRADUATE STUDIES Department o f F o r e s t r y We accept t h i s t h e s i s as conforming t o |the r e q u i r e d standard THE UNIVERSITY OF BRITISH COLUMBIA J u l y 1987 c c j C a r l o s Mario Di Lucca, 1987 MASTER OF SCIENCE i n In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department The University of British Columbia 1956 Main Mall Vancouver, Canada V6T 1Y3 Date AUGUST 7 / 3?1 DE-6(3/81) ABSTRACT The t r a n s i t i o n from old-growth t o second-growth B r i t i s h Columbia c o a s t a l D o u g l a s - f i r has r e s u l t e d i n r e d u c t i o n o f log s i z e and i n c r e a s e d p r o p o r t i o n o f j u v e n i l e (core or crown-formed) wood. Determination o f the zone o f t r a n s i t i o n from j u v e n i l e t o mature wood i s c r i t i c a l t o the d e f i n i t i o n o f wood q u a l i t y and timber va l u e . T h i r t e e n unpruned, two pruned second-growth, and two unpruned plantation-grown c o a s t a l D o u g l a s - f i r t r e e s were sampled t o an a l y z e the hy p o t h e s i s t h a t the t r a n s i t i o n i n r e l a t i v e d e n s i t y from j u v e n i l e t o mature wood occurs a t t h e base o f the l i v e crown. X-ray d e n s f t o m e t r i c techniques were u t i l i z e d t o determine y e a r l y p i t h t o bark r e l a t i v e d e n s i t y data o f f i v e c r o s s - s e c t i o n a l d i s c s from each t r e e . Segmented l i n e a r r e g r e s s i o n techniques were u t i l i z e d t o estimate the j u v e n i l e - mature wood t r a n s i t i o n age from the data. The average number o f growth increments from the p i t h a t which j u v e n i l e - mature wood t r a n s i t i o n o c c u r r e d on s e c t i o n s sampled a t b r e a s t h e i g h t , 20 percent and 40 percent o f t o t a l h e i g h t was 22.18. When the hypothesis was t e s t e d on unpruned t r e e s , b e f o r e and a f t e r h a r v e s t , the j u v e n i l e - mature wood t r a n s i t i o n o c c u r r e d below the base o f the l i v e crown. When t h e h y p o t h e s i s was t e s t e d o n p r u n e d t r e e s , t h e t r a n s i t i o n o c c u r r e d a t t h e b a s e o f t h e l i v e c r o w n , w h i c h r e p r e s e n t e d t h e u p p e r l i m i t o f p r u n i n g h e i g h t . T h i s i n f o r m a t i o n may p r o v i d e a g r e a t e r i n s i g h t i n t o j u v e n i l e - m a t u r e wood t r a n s i t i o n . I t wi11 l i k e l y a s s i s t i n t h e d e t e r m i n a t i o n o f wood q u a l i t y a n d e c o n o m i c v a l u e o f f o r e s t p r o d u c t s m a n u f a c t u r e d f r o m s e c o n d - g r o w t h c o a s t a l D o u g l a s - f i r . f V TABLE OF CONTENTS Page TITLE PAGE 1 ABSTRACT i i TABLE OF CONTENTS i v LIST OF TABLES v i LIST OF FIGURES v i i i LIST OF APPENDICES x i ACKNOWLEDGEMENT x i i i 1.0 INTRODUCTION 1 2.0 LITERATURE REVIEW 5 2. 1 Wood Format i on 5 2.1.1 Primary Growth 5 2.1.2 Secondary Growth 7 2.1.3 Influence o f the Crown on Wood Formation .. 10 2.2 J u v e n i l e and Mature Wood 13 2.2.1 Anatomical S t r u c t u r e Comparison 15 2.2.2 P h y s i c a l P r o p e r t i e s Comparison 17 2.2.2.1 R e l a t i v e D e n s i t y 19 2.2.2.2 Other P r o p e r t i e s 24 2.2.3 J u v e n i l e - Mature Wood T r a n s i t i o n Determination 26 2.2.3.1 S u b j e c t i v e Methods 27 2.2.3.2 O b j e c t i v e Methods 29 V 3.0 MATERIALS AND METHODS 33 3.1 E x t e r n a l Tree C h a r a c t e r i s t i c s 34 3.2 In t e r n a l Tree C h a r a c t e r i s t i c s 36 3.2.1 X-ray Dens i tometr i c Analyses 37 3.2.2 J u v e n i l e - Mature Wood T r a n s i t i o n Determination 38 4.0 RESULTS AND DISCUSSION 43 4.1 X-Ray D e n s i t o m e t r i c Analyses 43 4.2 J u v e n i l e - Mature Wood T r a n s i t i o n Determination .. 46 4.2.1 J u v e n i l e - Mature Wood R e l a t i v e D e n s i t y Values 50 4 . 3 Base o f the L i ve Crown 51 4.4 R e l a t i o n s h i p s Between J u v e n i l e - Mature Wood T r a n s i t i o n and the Base o f the L i v e Crown 54 4.4.1 Hypothesis T e s t i n g Before Harvest 55 4.4.2 Hypothesis T e s t i n g A f t e r Harvest 63 4.5 Pruned Trees 68 5.0 CONCLUSIONS 72 LITERATURE CITED 77 APPENDICES 130 v i LIST OF TABLES Table Page 1 D o u g l a s - f i r stand c h a r a c t e r i s t i c s 91 2 Sample t r e e c h a r a c t e r i s t i c s 92 3 Tree crown c h a r a c t e r i s t i c s 93 4 Summary o f r e l a t i v e d e n s i t y values f o r s e c t i o n s sampled a t b r e a s t h e i g h t (B.H.) 94 5 Summary o f r e l a t i v e d e n s i t y v a l u e s f o r s e c t i o n s sampled a t 20 percent o f t o t a l h e i g h t 95 6 Summary o f r e l a t i v e d e n s i t y values f o r s e c t i o n s sampled a t 40 percent o f t o t a l h e i g h t 96 7 Summary o f r e l a t i v e d e n s i t y values f o r s e c t i o n s sampled a t 60 percent o f t o t a l h e i g h t 97 8 Summary o f r e l a t i v e d e n s i t y v a l u e s f o r s e c t i o n s sampled a t 80 percent o f t o t a l h e i g h t 98 9 Summary o f the d i s t r i b u t i o n o f r e l a t i v e d e n s i t y p r o f i l e s which showed no J u v e n i l e - mature wood t r a n s i t i o n 99 10 T r a n s i t i o n d e t e r m i n a t i o n by comparing simple a g a i n s t segmented l i n e a r r e g r e s s i o n models on r e l a t i v e d e n s i t y p r o f i l e s 100 11 Summary o f the d i s t r i b u t i o n o f r e l a t i v e d e n s i t y p r o f i l e s which showed j u v e n i l e - mature wood t r a n s i t i o n 102 12 Summary o f the r e l a t i v e d e n s i t y values o f the p r o f i l e s which showed no j u v e n i l e - mature wood t r a n s i t i o n 103 13 Summary o f the r e l a t i v e d e n s i t y v a l u e s o f the p r o f i l e s which showed j u v e n i l e - mature Wood t r a n s i t i o n 104 14 O v e r a l l summary o f r e l a t i v e d e n s i t y v a l u e s f o r j u v e n i l e and mature wood 105 v i i 15 Summary o f sampled dead branch c h a r a c t e r i s t i c s .... 106 16 Summary o f lowest r e l a t i v e d e n s i t y v a l u e s 107 17 D i f f e r e n c e s between he i g h t o f j u v e n i l e - mature wood t r a n s i t i o n p o i n t , h e i g h t o f crown base and t o t a l h e i g h t 108 18 Summary o f hei g h t d i f f e r e n c e s t a t i s t i c s 109 19 C o r r e l a t i o n matrix f o r l i v e crown base h e i g h t , average crown h e i g h t , average t r a n s i t i o n h e i g h t A and average t r a n s i t i o n h e i g h t B 110 v i i i LIST OF FIGURES F igure Page 1 Location of Douglas-fir stands I l l 2 Pith to bark relative density profiles for sample tree 1A5 112 3 a) Segmented linear regression model on pith to bark relative density profile for a sample radi us 113 b) Simple linear regression model on pith to bark relative density profile for a sample radius 113 4 a) Scatter plot of height over number of growth increments at which juvenile - mature wood transition occurs 114 b) Scatter plot of height over number of growth increments at the base of dead branches for a l l trees 114 c) Scatter plot of height over number of growth increments which indicates the lowest relative density value in the profile 114 5 a) Scatter plot and height prediction model for crown base height over total height 115 b) Scatter plot and height prediction model for average crown height over total height 115 6 Scatter plot of a) total height and height prediction models over total height; for: b) average crown height; and c) crown base height ... 116 7 Graphical representation of: a) total tree height; and b) crown base height over number of growth increments from the pith 117 8 Graphical representation of: a) total tree height; b) crown base height before harvest; c) live crown base height at harvest; and d) average crown height at harvest over number of growth increments from the pith at breast height 118 fx 9 a) S c a t t e r and h e i g h t p r e d i c t i o n model f o r t o t a l t r e e height over number o f growth increments from the p i t h a t b r e a s t height 119 b) S c a t t e r and he i g h t p r e d i c t i o n model f o r lowest r e l a t i v e d e n s i t y over number o f growth increments from the p i t h a t b r e a s t h e i g h t 119 10 a) S c a t t e r and height p r e d i c t i o n model f o r h e i g h t t o crown base over number o f growth increments from the p i t h a t b r e a s t h e i g h t 120 b) S c a t t e r and h e i g h t p r e d i c t i o n model f o r j u v e n i l e - mature wood t r a n s i t i o n p o i n t s over number o f growth increments from the p i t h a t b r e a s t h e i g h t 120 11 Height p r e d i c t i o n models f o r : a) t o t a l t r e e h e i g h t ; b) lowest r e l a t i v e d e n s i t y h e i g h t ; c) crown base h e i g h t ; d) J u v e n i l e - mature wood t r a n s i t i o n h e i g h t over number o f growth increments from the p i t h a t b r e a s t h e i g h t ; and e) d i a g r a m a t i c t r e e r e p r e s e n t a t i o n s 121 12 a) S c a t t e r and he i g h t p r e d i c t i o n model f o r the d i f f e r e n c e between crown base h e i g h t and j u v e n i l e - mature wood t r a n s i t i o n h eight over j u v e n i l e - mature wood t r a n s i t i o n h e i g h t . 122 b) S c a t t e r and h e i g h t p r e d i c t i o n model f o r the d i f f e r e n c e between t o t a l h e i g h t and j u v e n i l e - mature wood t r a n s i t i o n h e i g h t over j u v e n i l e - mature wood t r a n s i t i o n h e i g h t . 122 13 G r a p h i c a l r e p r e s e n t a t i o n o f : a) e s t i m a t i o n o f the average t r a n s i t i o n h e i g h t A; and b) e s t i m a t i o n o f the average t r a n s i t i o n h eight h e i g h t B over number o f growth increments from th e p i t h a t b r e a s t h e i g h t 123 14 S c a t t e r p l o t o f j u v e n i l e - mature ( J . M.) wood t r a n s i t i o n number o f growth increments over t r e e s e c t i o n s and o v e r a l l s e c t i o n averages, i . e . average t r a n s i t i o n age A 124 15 S c a t t e r p l o t o f he i g h t d i f f e r e n c e s among t o t a l and t r a n s i t i o n h e i g h t s over t r e e s e c t i o n s and o v e r a l l s e c t i o n averages, i . e . average t r a n s i t i o n h e i g h t B 125 16 a) S c a t t e r p l o t and h e i g h t p r e d i c t i o n model f o r average t r a n s i t i o n h e i g h t A over t o t a l h e i g h t . 126 b) S c a t t e r p l o t and he i g h t p r e d i c t i o n model f o r average t r a n s i t i o n h e i g h t B over t o t a l h e i g h t . 126 X 17 S c a t t e r p l o t o f a) t o t a l t r e e h e i g h t , and height p r e d i c t i o n models over t o t a l h e i g h t f o r : b) average crown h e i g h t ; c) average t r a n s i t i o n h e i g h t A; d) l i v e crown base h e i g h t ; and e) average t r a n s i t i o n h e i g h t B 127 18 P i t h t o bark r e l a t i v e d e n s i t y p r o f i l e s f o r pruned t r e e RF2 128 19 P i t h t o bark r e l a t i v e d e n s i t y p r o f i l e s f o r pruned t r e e RF3 129 x i LIST OF APPENDICES Appendi x Page 1 Average Crown Height. E s t i m a t i o n Procedure 130 a) R e l a t i o n s h i p between t o t a l branch length (BL) and the v e r t i c a l d i s t a n c e from the leader (L) f o r Sample Tree 1A5 132 b) R e l a t i o n s h i p between t o t a l branch length (BL) and the transformed v e r t i c a l d i s t a n c e from the leader In [ (L/c)+l ] f o r Sample Tree 1A5 . 133 c) Average crown he i g h t p o s i t i o n d e t e r m i n a t i o n f o r Sample Tree 1A5 134 2 R e l a t i o n s h i p between t o t a l h e i g h t and branch age t o e s timate base o f l i v e crown p o s i t i o n s a t young ages 135 3 Summary o f X-Ray Dens?tometric A n a l y s i s Procedure 136 4 F o r t r a n program t o determine r e s i d u a l sum o f squares u s i n g n o n - l i n e a r o p t i m i z a t i o n r o u t i n e s f o r segmented r e g r e s s i o n models 138 5 Tree 1A5 139 6 Tree 1A7 140 7 Tree 1B6 141 8 Tree 1B11 142 9 Tree 1C1 143 10 Tree 1C6 144 11 Tree 1D5 145 12 Tree 1D6 146 13 Tree 1E3 147 14 Tree 1E8 148 15 Tree 1F7 149 x i i 16 Tree IF 10 150 17 Tree CR 1 15 1 18 Tree CR2 152 19 Tree RF 1 153 20 Summary o f r e l a t i v e d e n s i t y d a t a : a) Tree 1A5 154 b) Tree 1A7 154 c) Tree 1B6 155 d) Tree IBM 155 e) Tree 1C1 156 f ) Tree 1C6 156 g) Tree 1D5 157 h) Tree 1D6 157 i ) Tree 1E3 158 j ) Tree 1E8 158 k) Tree 1F7 159 1) Tree IF 10 159 m) Tree CR1 160 n) Tree CR2 160 o) Tree RF 1 161 p) Tree RF2 161 q) Tree RF3 162 x i i i ACKNOWLEDGEMENT The author acknowledges, with g r a t i t u d e , Dr. J.W. Wilson, F a c u l t y o f F o r e s t r y , The U n i v e r s i t y o f B r i t i s h Columbia, Dr. R.M. K e l l o g g , F o r i n t e k Canada C o r p o r a t i o n and Dr. K.J. M i t c h e l l , M i n i s t r y o f F o r e s t s and Lands o f B r i t i s h Columbia, under whose guidance and s u p e r v i s i o n t h i s p r o j e c t was accomplished. A p p r e c i a t i o n i s a l s o due t o Dr. P. M a r s h a l l , F a c u l t y o f F o r e s t r y , The U n i v e r s i t y o f B r i t i s h Columbia, f o r h i s a d v i c e and review o f the t h e s i s . G r a t e f u l acknowledgement i s giv e n t o L.A. Joz s a , S.G. Johnson, J . Cook and J . Ri c h a r d s , F o r i n t e k Canada C o r p o r a t i o n , f o r t h e i r v a l u a b l e a s s i s t a n c e d u r i n g experimental phases o f the study. A p p r e c i a t i o n i s extended t o F o r i n t e k Canada C o r p o r a t i o n f o r the use o f t h e i r l a b o r a t o r y f a c i l i t i e s and m a t e r i a l s . S p e c i a l thanks i s due t o J.C. F a h l e r , E s t . Las Marias, A r g e n t i n a , f o r i n s p i r i n g t he author's i n t e r e s t i n the study o f f o r e s t r y . The deepest g r a t i t u d e i s expressed t o my w i f e , Barbara, f o r her p a t i e n c e and encouragement. F i n a l l y , the author i s a p p r e c i a t i v e o f the f i n a n c i a l support p r o v i d e d by t h e Research C o u n c i l o f B r i t i s h Columbia, the M i n i s t r y o f F o r e s t s and Lands o f B r i t i s h Columbia and the Canadian F o r e s t S e r v i c e . 1 1.0 INTRODUCTION Coastal D o u g l a s - f i r (Pseudotsuga menz i es i i (Mirb.) Franco) i s found west o f the Cascade Range in Washington and Oregon, west of the Coast Range in B r i t i s h Columbia and west o f the S i e r r a Nevada in northern C a l i f o r n i a . The north - south range o f the s p e c i e s extends approximately 3400 km south from the c e n t r a l B r i t i s h Columbia coast ( L a t . 55°N) ( F o w e l l s , 1965). Coastal D o u g l a s - f i r i s a r e l a t i v e l y minor s p e c i e s i n B r i t i s h Columbia. Reserves o f c o a s t a l D o u g l a s - f i r i n t h e Vancouver and P r i n c e Rupert r e g i o n s amount t o approximately 126 m i l l i o n c u b i c metres, which r e p r e s e n t s i x percent o f the t o t a l mature timber and s i x percent o f the annual timber h a r v e s t e d in 1980 ( B r i t i s h Columbia M i n i s t r y o f F o r e s t s , 1980). However, because o f easy a c c e s s , high q u a l i t y and developed markets, D o u g l a s - f i r i s h i g h l y demanded and the most i n t e n s i v e l y managed commercial s p e c i e s . For these reasons, the old-growth c o a s t a l D o u g l a s - f i r r e source has been almost r e p l a c e d by young and f a s t grown second-growth timber. The t r a n s i t i o n t o second-growth timber has r e s u l t e d in r e d u c t i o n o f log s i z e and changes i n the q u a l i t y o f the raw m a t e r i a l . These changes are demonstrated by the i n c r e a s e d p r o p o r t i o n o f j u v e n i l e (core or crown-formed) wood found i n 2 the second-growth timber. Compared t o mature (stem-formed) wood, the j u v e n i l e wood o f D o u g l a s - f i r i s c h a r a c t e r i z e d by lower r e l a t i v e d e n s i t y , s h o r t e r t r a c h e i d s , l a r g e r f i b r i l a n gle, lower s t r e n g t h , lower percentage o f latewood, lower t r a n s v e r s e shrinkage, higher l o n g i t u d i n a l shrinkage, lower c e l l u l o s e content and higher l i g n i n content (Bendtsen, 1978; B a r r e t t and K e l l o g g , 1984, 1986; Jackson and Megraw, 1986; Jozsa and K e l l o g g , 1986; McKimmy, 1986). Such d i f f e r e n c e s i n wood p r o p e r t i e s a r e very important i n t h e p r o c e s s i n g and manufacturing o f lumber, veneer, c h i p s and other f o r e s t p r o d u c t s . The f u t u r e o f the Canadian f o r e s t i n d u s t r y w i l l depend upon t h e s u c c e s s f u l c o n v e r s i o n and c o m m e r c i a l i z a t i o n o f f o r e s t products manufactured from second-growth timber. In order t o m a i n t a i n and improve wood supply the i n d u s t r y needs i n f o r m a t i o n t o p l a n and p r e d i c t the e f f e c t s o f i n t e n s i v e f o r e s t management on volume p r o d u c t i o n , p r o p e r t i e s and value o f second-growth timber ( K e l l o g g , 1986). The Tree and Stand S i m u l a t o r (TASS) ( M i t c h e l l , 1975; M i t c h e l l and Cameron, 1985) models the growth and y i e l d o f second-growth c o a s t a l D o u g l a s - f i r under d i f f e r e n t management c o n d i t i o n s . T h i s i s a b i o l o g i c a l l y o r i e n t e d model which can s i m u l a t e crowns o f i n d i v i d u a l t r e e s i n a three-di m e n s i o n a l growing space in response t o i n t e r n a l 3 growth p r o c e s s e s , environmental f a c t o r s , p h y s i c a l r e s t r i c t i o n s and c u l t u r a l p r a c t i c e s . However, the model does not c o n s i d e r wood q u a l i t i e s or value o f wood pro d u c t s . In view o f the above, F o r i n t e k Canada C o r p o r a t i o n , the Pulp and Paper Research I n s t i t u t e o f Canada, the M i n i s t r y of F o r e s t s and Lands o f B r i t i s h Columbia and the U n i v e r s i t y o f B r i t i s h Columbia have i n i t i a t e d n i ne i n t e g r a t e d p r o j e c t s t o p r o v i d e much o f the t e c h n i c a l i n f o r m a t i o n r e q u i r e d f o r f u t u r e u t i l i z a t i o n p l a n n i n g f o r second-growth c o a s t a l D o u g l a s - f i r ( K e l l o g g , 1986). The purpose o f t h i s t h e s i s p r o j e c t , which i s one o f the nine D o u g l a s - f i r Task Force p r o j e c t s , fs t o i n v e s t i g a t e the t r a n s i t i o n i n r e l a t i v e d e n s i t y between j u v e n i l e and mature wood. The s p e c i f i c o b j e c t i v e o f t h i s study i s t o t e s t and a n a l y z e the hypothes i s t h a t : The r e l a t i v e d e n s i t y t r a n s i t i o n from J u v e n i l e t o mature wood i n i n d i v i d u a l growth increments o f second-growth c o a s t a l D o u g l a s - f i r t r e e s o c c u r s a t the base o f the l i v e crown. To t e s t t h i s h y p o t h e s i s , 13 unpruned, two pruned second-growth, and two unpruned plantation-grown t r e e s were sampled and an a l y z e d . 4 It fs hoped t h a t the r e s u l t s o f t h i s p r o j e c t w i l l c o n t r i b u t e t o the understanding o f how and when the r e l a t i v e d e n s i t y t r a n s i t i o n between j u v e n i l e and mature wood o c c u r s . Furthermore, the r e s u l t s can h e l p extend TASS t o s i m u l a t e the p r o d u c t i o n o f j u v e n i l e and mature wood, thus p r o v i d i n g i n s i g h t i n t o i n t e r a c t i o n s o f stand dynamics and wood q u a l i t y . In a d d i t i o n , the f i n d i n g s o f t h i s p r o j e c t a re l i k e l y t o be o f va l u e t o the D o u g l a s - f i r Task Force and the general f o r e s t r y i n d u s t r y i n the d e t e r m i n a t i o n o f wood q u a l i t y and, u l t i m a t e l y , economic value o f f o r e s t products i n B r i t i s h Columbia. 5 2.0 LITERATURE REVIEW 2.1 Wood Formation The p h y s i o l o g i c a l processes c o n t r o l l i n g wood form a t i o n in temperate zone t r e e s a r e r e l a t e d t o the seasonal a c t i v i t y o f the v a s c u l a r cambium and d i f f e r e n t i a t i o n o f i t s der i vat i ves. In c o n i f e r o u s t r e e s , t h e r e i s a high c o r r e l a t i o n between growth and development o f the crown over time and wood fo r m a t i o n along the stem (Larson, 1964, 1969). The p h y s i o l o g y o f wood fo r m a t i o n must, then, be c o n s i d e r e d as an i n t e g r a l p a r t o f t r e e growth. T h i s growth can be d i v i d e d i n t o two developmental stages, a primary stage o r i g i n a t i n g i n the v e g e t a t i v e t e r m i n a l buds, and a secondary stage o r i g i n a t i n g i n the v a s c u l a r cambium. 2.1.1 Primary Growth The primary growth stage encompasses the e l o n g a t i o n o f the main stem and branches and the r e g u l a t i o n o f height growth and t r e e form. In temperate zone c o n i f e r s , the seasonal primary growth begins as a r e s u l t o f an i n c r e a s e in temperature and day length i n e a r l y s p r i n g (Wilcox, 1962; Panshin and de Zeeuw, 1980). These changes i n 6 environmental c o n d i t i o n s i n i t i a t e primary c e l l d i v i s i o n a f t e r the r e h y d r a t i o n , s w e l l i n g and i n c r e a s e o f hormonal and enzymatic a c t i v i t y i n the a p i c a l men"stems i n s i d e the v e g e t a t i v e buds. In D o u g l a s - f i r , t h i s growth a c t i v a t i o n o c curs i n the l a s t week o f March a t lower e l e v a t i o n s (Owens, 1968; A l l e n and Owens, 1972). As the growing season advances, more new c e l l s are formed c a u s i n g primary shoot e l o n g a t i o n i n the stem and branches. Subsequently, the newly formed c e l l s undergo d i f f e r e n t i a t i o n , r e s u l t i n g i n changes i n s i z e , shape and f u n c t i o n . In t h i s manner, primary permanent t i s s u e s are d i f f e r e n t i a t e d from t h r e e m e r i s t e m a t i c t i s s u e s c a l l e d protoderm, ground meristem and procambium (Kowlowski, 1971). The protoderm develops an e x t e r n a l p r o t e c t i v e l a y e r c a l l e d the e p i d e r m i s . The ground meristem develops i n t o the c e n t r a l p i t h and c o r t e x . The procambium g i v e s r i s e t o the primary phloem and primary xylem and subsequently the v a s c u l a r cambium. The primary phloem i s formed on the o u t e r s i d e o f the procambium. It performs the f u n c t i o n o f m o b i l i z a t i o n and t r a n s p o r t o f sugar and o t h e r n u t r i e n t s w i t h i n the shoot apex. The primary xylem i s formed on the inner s i d e o f t h e procambium and i t performs the f u n c t i o n o f support and conduction o f d i s s o l v e d substances from the r o o t s t o t h e t e r m i n a l shoots. 7 The v a s c u l a r cambium, a secondary m e r i s t e m a t i c t i s s u e r e s p o n s i b l e f o r the l a t e r a l growth o f xylem (wood), and phloem (bark) t i s s u e s , i s formed a f t e r completion o f the d i f f e r e n t i a t i o n o f primary permanent t i s s u e s . It i s made up o f f u s i f o r m and ray cambial i n i t i a l c e l l s , and separates the xylem and phloem mother c e l l s . 2.1.2 Secondary Growth The secondary growth stage, as i t r e l a t e s t o wood fo r m a t i o n , can be summarized i n t o t h e f o l l o w i n g developmental phases (Larson, 1969; Brown, 1970; Kozlowski, 1971; Wilson, 1984; Haygreen and Bowyer, 1982): 1. Awakening, r e h y d r a t i o n and s w e l l i n g o f the dormant cambium a t the b e g i n n i n g o f the growing season; 2. P e r i c l i n a l d i v i s i o n o f f u s i f o r m cambial i n i t i a l c e l l s r e s u l t i n g i n the f o r m a t i o n o f new m e r i s t e m a t i c c e l l s , and new xylem and phloem mother c e l l s with c e l l d i v i s i o n peaking a few weeks i n t o the growing season, a f t e r which i t decreases g r a d u a l l y u n t i l completed i n e a r l y summer; 8 3. D i f f e r e n t i a t i o n o f the xylem and phloem cambial mother c e l l s p a s s i n g through the phases o f enlargement, and secondary wall f o r m a t i o n and t h i c k e n i n g ; and 4 . F i n a l l y , maturation o f the newly formed xylem and phloem c e l l s , thus completing the secondary wall t h i c k e n i n g and 1 i g n i f i c a t i o n phases. The annual a d d i t i o n o f newly formed secondary phloem c e l l s forms the bark, which i s d i v i d e d i n t o a l i g h t c o l o u r e d inner l i v i n g bark and a dark o u t e r dead bark. The annual a d d i t i o n s o f secondary xylem c e l l s form c o n c e n t r i c l a y e r s or r i n g s o f growth increments t h a t a r e r e s p o n s i b l e f o r the i n c r e a s e i n stem and branch diameters (Panshin and de Zeeuw, 1980). The annual growth increments are c h a r a c t e r i z e d by the f o r m a t i o n o f two zones c a l l e d ear 1ywood (spr i ngwood) and 1 atewood (summerwood). The most important anatomical d i f f e r e n c e s between ear 1ywood and latewood a r e the r a d i a l c e l l diameter and the secondary wall t h i c k n e s s . Such c h a r a c t e r i s t i c s a r e known t o be independent o f each o t h e r (Richardson and Dinwoodie, 1960; Wodzicki, 1960). T h e i r f o r m a t i o n , p a r t i c u l a r l y i n pine t r e e s , was e x p l a i n e d by Wareing (1958) and Larson (1963, 1969) i n the f o l l o w i n g two hypotheses. 9 The f i r s t i s the hormonal or aux i n h y p o t h e s i s , which i s r e l a t e d t o the r e g u l a t i o n o f t r a c h e i d diameter. During the p e r i o d o f a c t i v e shoot e l o n g a t i o n and needle development i n t h e s p r i n g , a high l e v e l o f d i f f u s i b l e a u x i n i s produced w i t h i n the v e g e t a t i v e buds and t r a n s p o r t e d downward a l o n g each branch, down the main stem and i n t o the r o o t s . Then, the cambial a c t i v i t y begins with the p r o d u c t i o n o f large diameter xylem t r a c h e i d s c l a s s i f i e d as earlywood. Earlywood f o r m a t i o n c o n t i n u e s as long as the e l o n g a t i n g shoots and d e v e l o p i n g needles compete f o r the s t o r e d and c u r r e n t l y produced photosynthates. As the growing season advances, narrow diameter latewood t r a c h e i d s are produced i n response t o the c e s s a t i o n o f t e r m i n a l growth, the r e d u c t i o n o f a u x i n s y n t h e s i s , and the i n c r e a s e o f growth i n h i b i t i n g substances. The f o r m a t i o n o f latewood t r a c h e i d s begins a t or near the base o f the t r e e and t a p e r s upwards t o a p o i n t o f e x t i n c t i o n near the apex. The second h y p o t h e s i s e x p l a i n s the secondary c e l l w all t h i c k e n i n g , which i s r e l a t e d t o the net amount o f photosynthates t h a t reach each t r a c h e i d a f t e r r e s p i r a t i o n requirements have been met. The c o m p e t i t i o n f o r photosynthates among me r i s t e m a t i c t i s s u e s decreases, and the r a t e o f p h o t o s y n t h e s i s i n the c u r r e n t year needles r a p i d l y i n c r e a s e s ( F r e e l a n d , 1952; C l a r k , 1961). Thus, more photosynthates a r e a v a i l a b l e f o r both stem growth and 10 secondary wal1 t h i c k e n i n g o f the latewood t r a c h e i d s ( R u t t e r , 1957). 2.1.3 I n f l u e n c e o f the Crown on Wood Formation The hormonal and the secondary wal1 t h i c k n e s s r e g u l a t i o n hypotheses emphasize t h a t earlywood and latewood t r a c h e i d formations a r e c o r r e l a t e d t o photosynthate a v a i l a b i l i t y and presence o f a u x i n . These crown formed products determine the r a t e o f cambial i n i t i a l c e l l d i v i s i o n and the degree o f d i f f e r e n t i a t i o n o f the cambial d e r i v a t i v e s . It fs c l e a r t h a t the growth and development o f the crown over time has a d i r e c t r e g u l a t o r y i n f l u e n c e over wood form a t i o n i n the stem (Larson, 1962, 1964). W i t h i n the crown, the most v i g o r o u s l y a c t i v e l i v e branches w i l l r e g u l a t e the wood f o r m a t i o n by a steady p r o d u c t i o n o f photosynthates and a u x i n s . These branches are c h a r a c t e r i z e d by having complete growth increments a l o n g t h e i r length forming an a c t i v e union w i t h the main stem. As the branches s t a r t t o compete f o r l i g h t and become o l d e r and longer, t h e i r v i g o r , g i v e n by the c a p a c i t y o f p r o d u c i n g photosynthates and a u x i n s , g r a d u a l l y decreases (Larson, 1969). T h i s leads t o a decrease i n the c u r r e n t shoot length from the apex t o the base o f the l i v e crown and from the t i p t o the base o f the branch ( F r a s e r , 1962; Forward and Nolan, 1964). 11 The decrease i n branch v i g o r i s f o l l o w e d by a p e r i o d o f senescence which s t a r t s a t the lower crown branches. At t h i s time the c o n t r i b u t i o n o f these branches t o wood for m a t i o n g r a d u a l l y decreases, l e a d i n g t o the for m a t i o n o f incomplete or absent growth increments a t the branch base (Andrew and G i l l , 1939; Reukema, 1959, 1961; Reeb, 1984). These senescent branches, which a r e s t i l l a t t a c h e d t o the main stem, i n t e r r u p t t h e i r c o n t a c t with the main t r a n s l o c a t i o n pathways i n the t r e e , r e s u l t i n g i n d i m i n i s h i n g c o n t r i b u t i o n t o wood f o r m a t i o n u n t i l branch death o c c u r s . Larson (1969) concluded t h a t major changes in wood fo r m a t i o n and q u a l i t y occur below the l i v i n g crown, or below the most a c t i v e branches o f t h e crown. For t r e e growth a n a l y s i s purposes, the h e i g h t t o l i v e crown base has been d e f i n e d i n s e v e r a l ways. Smith e t a 1. (1961) and M i t c h e l l (1969, 1975) d e f i n e d the height t o l i v e crown as the average d i s t a n c e from the ground t o the lowest l i v e branch i n each o f f o u r quadrants. They a l s o d e f i n e d an average l i v e crown h e i g h t as the average height from the ground t o the p o i n t o f maximum crown spread or crown r a d i u s . T h i s p o i n t o c c a s i o n a l l y r e p r e s e n t s the crown c o n t a c t with the crowns o f neighbouring t r e e s . Reeb (1984) d e f i n e d h e i g h t t o l i v e crown base as the h e i g h t from the ground t o the whorl a t which a t l e a s t 75 percent o f the branches a r e a l i v e . 12 The number o f growth increments a t the base o f the dead branches and the c o r r e s p o n d i n g h e i g h t p o s i t i o n s can be u t i l i z e d t o determine the approximate crown base p o s i t i o n s at younger ages. The age o f the t r e e a l s o has an i n f l u e n c e on wood fo r m a t i o n . A young t r e e with a high percentage o f the stem covered with a c t i v e l i v e branches w i l l produce wide growth increments with a high p r o p o r t i o n o f earlywood t r a c h e l d s . T h i s i s e x p l a i n e d by the prolonged i n f l u e n c e o f the a p i c a l meristems on the cambial r e g i o n s i n the a c t i v e l i v e crown. As the t r e e grows o l d e r and d i s t a n c e from both the p i t h and the a c t i v e l i v e crown i n c r e a s e s , the p r o p o r t i o n o f latewood t r a c h e i d s i n the growth increments g r a d u a l l y i n c r e a s e s . Now, the cambial r e g i o n s below the crown become l e s s i n f l u e n c e d by the a p i c a l meristems. Consequently, two c h a r a c t e r i s t i c wood zones can be d i f f e r e n t i a t e d w i t h i n the t r e e stem as a f u n c t i o n o f d i s t a n c e from the a c t i v e l i v e branches and number o f growth increments from the p i t h . The f i r s t zone, c a l l e d j u v e n i l e wood, forms a c e n t r a l core o f wood around the p i t h extending from t h e base t o the apex of the t r e e . The second, c a l l e d mature wood, i s formed around the j u v e n i l e wood core and below the l i v i n g crown. 13 2.2 J u v e n i l e and Mature Wood A u n i v e r s a l d e f i n i t i o n o f the terms j u v e n i l e and mature wood has not been agreed upon, although such terms can a r b i t r a r i l y d e s c r i b e the type o f wood produced i n r e l a t i o n t o crown p r o x i m i t y and number o f growth increments from the p i t h . S everal authors have d e f i n e d j u v e n i l e and mature wood from d i f f e r e n t p o i n t s o f view. For i n s t a n c e , when c o n s i d e r i n g the j u v e n i l e and mature wood stem p o s i t i o n s i n a t r e e , j u v e n i l e wood has been c a l l e d core, inner, or p i t h - a s s o c i a t e d wood and mature wood has been c a l l e d e x t e r i o r , o u t e r or n o n - p i t h - a s s o c i a t e d wood (Perry and Wang, 1958; Zobel et a]_. , 1959; Moody, 1970). J u v e n i l e wood has been c a l l e d immature or y o u t h f u l wood and mature wood has been c a l l e d o l d or a d u l t wood, based on t h e i r r e s p e c t i v e p h y s i o l o g i c a l stages o f m a t u r i t y (Rendle, 1958, 1959, 1960). J u v e n i l e wood has been c a l l e d crown-formed wood, because i t i s formed i n s i d e the l i v i n g crown, and mature wood has been c a l l e d stem-formed wood due t o i t s f o r m a t i o n o u t s i d e o f the l i v i n g crown (Trendelenburg, 1935; Cooper, 1960; Brunden, 1964; Larson, 1969, 1973). The s i z e o f the j u v e n i l e wood core g e n e r a l l y depends upon the growth r a t e , r e g a r d l e s s o f the s p e c i e s . Si 1 v i c u l t u r a l p r a c t i c e s such as f e r t i l i z a t i o n , i r r i g a t i o n 14 and t h i n n i n g w i l l tend t o decrease crown r e c e s s i o n and in c r e a s e crown v i g o r , growth r a t e and the s i z e o f the j u v e n i l e wood core (Bendtsen, 1978; B r i g g s and Smith, 1986; Megraw, 1985; O l i v e r , 1986). The p r o p o r t i o n o f the j u v e n i l e wood core i n the stem i s a f u n c t i o n o f the s p e c i e s , number o f growth increments from the p i t h and d i s t a n c e from the a c t i v e l i v e crown (Pa u l , 1960; Bendtsen, 1978). T h i s p r o p o r t i o n tends t o be high i n e a r l y harvested t r e e s and i n open-grown t r e e s . I n c r e a s i n g crown r e c e s s i o n by d e l a y i n g the h a r v e s t i n g age o f stand-grown t r e e s w i l l decrease the j u v e n i l e wood p r o p o r t i o n a t har v e s t age. An abrupt change from j u v e n i l e t o mature wood can a l s o be ac h i e v e d by pruning the l i v e and vigor o u s lower branches i n the crown (Marts, 1949; G e r i s c h e r and De V i l i f e r s , 1963; Smith, 1968; Larson, 1965, 1969; Cown, 1973; Polge et aj_. , 1973; Plumptre and A u s t i n , 1978). It i s e v i d e n t t h a t growth and development o f t h e a c t i v e l i v e crown as a f u n c t i o n o f age w i l l determine not o n l y the c h a r a c t e r i s t i c s o f the t r a c h e i d s formed, but a l s o the q u a n t i t y and q u a l i t y o f j u v e n i l e and mature wood i n t h e stem. J u v e n i l e and mature wood must be c o n s i d e r e d as two d i f f e r e n t p o p u l a t i o n s w i t h i n the same t r e e because o f t h e i r fundamental d i f f e r e n c e s i n wood q u a l i t y (Panshin and de 15 Zeeuw, 1980). Such d i f f e r e n c e s a re determined p r i m a r i l y by the t r a c h e i d s ' anatomical s t r u c t u r e and chemical composition, and s e c o n d a r i l y by the d e r i v e d p h y s i c a l wood pr o p e r t i es. 2.2.1 Anatomical S t r u c t u r e Comparison When c o n s i d e r i n g the t r a c h e i d anatomical s t r u c t u r e v a r i a t i o n s i n stem c r o s s - s e c t i o n s o f most c o n i f e r s , the lengt h , diameter and secondary wall t h i c k n e s s o f the j u v e n i l e wood t r a c h e i d s i n c r e a s e p r o g r e s s i v e l y from the p i t h u n t i l they more or l e s s s t a b i l i z e i n t h e mature wood (Bendtsen, 1978; Panshin and de Zeeuw, 1980; Megraw, 1985; Krahmer, 1986). In softwoods, the length o f mature wood t r a c h e i d s can be up t o t h r e e o r f o u r times g r e a t e r than t h a t o f j u v e n i l e wood t r a c h e i d s (Anderson, 1951; Dadswel1, 1958; Dinwoodie, 1961). Many s t u d i e s have shown t h a t the t r a c h e i d s i n j u v e n i l e wood are s h o r t e r than i n mature wood, r e g a r d l e s s o f h e i g h t . These r e s u l t s were r e p o r t e d by Zobel and K e l l i s o n (1972) f o r l o b l o l l y pine (Pinus taeda L . ) , by Loo et a l . (1985) f o r s l a s h p i n e (Pinus e 1 1 i o t t i i Engelm.), by Wang and Micko (1984) f o r white spruce ( P i c e a g1auca (Moench.) Voss ) , by E r i c k s o n and H a r r i s o n (1974) and Jackson and Megraw (1986) f o r D o u g l a s - f i r , by Boone and 16 Chudnoff (1972) f o r Caribbean pine (Pinus c a r i b a e a M o r e l e t . ) , by Cown (1975) f o r r a d i a t a p i n e (Pinus r a d i a t a D.Don), and by Well wood and Jurazs (1968) f o r western redcedar (Thu.ia p 1 i c a t a Donn.). The secondary wall t h i c k n e s s o f the j u v e n i l e wood t r a c h e i d s was r e p o r t e d t o be l e s s than t h a t o f mature wood t r a c h e i d s by Zobel and K e l l i s o n (1972) f o r l o b l o l l y p i n e , by Isebrands et al_. (1982) f o r l a r c h ( L a r i x spp.), by Cown (1975) f o r r a d i a t a pine and by F o e l k e l e t al.. (1976) f o r s l a s h p i n e . E r i c k s o n and H a r r i s o n (1974) found t h a t i n D o u g l a s - f i r the r a d i a l and t a n g e n t i a l diameter o f the j u v e n i l e wood t r a c h e i d i n c r e a s e d toward mature wood. In a d d i t i o n t o the above f i n d i n g s , the lumen s i z e , and the m i c r o f i b r i l angle o f t h e S2 l a y e r o f the j u v e n i l e wood t r a c h e i d s g e n e r a l l y decrease toward mature wood, where they s t a b i l i z e t o some e x t e n t . The decrease i n lumen s i z e from j u v e n i l e t o mature wood t r a c h e i d s was r e p o r t e d by Zobel and K e l l i s o n (1972) f o r l o b l o l l y p i n e , by F o e l k e l e t aj.. (1976) f o r s l a s h p i n e , and by Cown (1975) f o r r a d i a t a p i n e . The decrease i n m i c r o f i b r i l angle from j u v e n i l e t o mature wood t r a c h e i d s was found by Meylan (1968) f o r r a d i a t a p i n e , by Boone and Chudnoff (1972) f o r Caribbean p i n e , and by E r i c k s o n and Arfma (1974) f o r D o u g l a s - f i r . 17 V a r i a t i o n s i n the chemical composition o f t r a c h e i d s i n c l u d e the f o l l o w i n g . The h o l o c e l l u l o s e and al p h a c e l l u l o s e contents o f the j u v e n i l e wood t r a c h e i d s g r a d u a l l y i n c r e a s e from the p i t h u n t i l they begin t o s t a b i l i z e i n the mature wood. However, an i n v e r s e r e l a t i o n s h i p occurs with some h e m i c e l l u l o s e s and l i g n i n , which decrease from j u v e n i l e t o mature wood. These tre n d s can be seen from the data o f K i r k et aj_. (1972) and Zobel and K e l l f s o n (1972) on l o b l o l l y p i n e , Schmidt and Smith (1961) on Caribbean p i n e . Well wood and Smith (1962), Kennedy and Jaworsky (1960), S a s t r y and Wei 1 wood (1971), E r i c k s o n and H a r r i s o n (1974), and Megraw (1985) on D o u g l a s - f i r . In c o n c l u s i o n , i n comparison t o mature wood, the j u v e n i l e wood i n D o u g l a s - f i r i s c h a r a c t e r i z e d by s m a l l e r and s h o r t e r t r a c h e i d s w i t h t h i n n e r w a l l s and l a r g e r m i c r o f i b r i l a n g l e s , and by lower h o l o c e l 1 u l o s e and alpha c e l l u l o s e c o n t e n t s and high e r l i g n i n and h e m i c e l l u l o s e c o n t e n t s . 2.2.2 P h y s i c a l P r o p e r t i e s Comparison Anatomical and chemical d i f f e r e n c e s among t r a c h e i d s , as d e s c r i b e d , i n f l u e n c e the p h y s i c a l p r o p e r t i e s and, t h e r e f o r e , the q u a l i t y o f j u v e n i l e and mature wood. To d e f i n e wood q u a l i t y , Larson (1969) s t a t e d : 18 "During the wood fo r m a t i o n process numerous f a c t o r s both i n s i d e and o u t s i d e the t r e e lead t o v a r i a t i o n in type, number, s i z e , shape, p h y s i c a l s t r u c t u r e and chemical composition o f the wood elements. Wood q u a l i t y i s an a r b i t r a r y c l a s s i f i c a t i o n o f these v a r i a t i o n s in the wood elements when they a r e counted, measured, weighed, a n a l y z e d or e v a l u a t e d f o r some s p e c i f i c purpose." The q u a l i t y o f wood, then, r e f e r s t o i t s f i t n e s s f o r p a r t i c u l a r u t i l i z a t i o n , each q u a l i t y being determined by a c e r t a i n number o f p r o p e r t i e s . For i n s t a n c e , r e l a t i v e d e n s i t y , s t r e n g t h , e l a s t i c i t y , p r o p o r t i o n o f corewood, r e a c t i o n wood, g r a i n o r i e n t a t i o n , p e r m e a b i l i t y , moisture content and presence o f knots a r e some o f the p r o p e r t i e s which determine the s u i t a b i l i t y o f wood f o r a s p e c i f i c end use ( F i e l d i n g , 1967; Haygreen and Bowyer, 1982). When c o n s i d e r i n g softwood as a raw m a t e r i a l source f o pulp and lumber p r o d u c t i o n , r e l a t i v e d e n s i t y i s one o f the most important c h a r a c t e r i s t i c s t o be c o n s i d e r e d as a general i n d i c a t o r o f wood q u a l i t y . The reason i s t h a t r e l a t i v e d e n s i t y i s h i g h l y c o r r e l a t e d t o p u l p y i e l d , paper-making p r o p e r t i e s and s t r e n g t h p r o p e r t i e s o f timber (Bar e f o o t et aj_. , 1970; Gonzalez and K e l l o g g , 1978; K e l l o g g , 1982;). 19 2.2.2.1 R e l a t i v e D e n s i t y R e l a t i v e d e n s i t y , o f t e n c a l l e d s p e c i f i c g r a v i t y i n wood q u a l i t y s t u d i e s , expresses how much c e l l wall substance i s present i n a g i v e n volume o f wood. R e l a t i v e d e n s i t y i s the r a t i o o f the weight o f a giv e n volume o f wood t o the weight o f an equal volume o f water. I t can be c a l c u l a t e d based on oven-dry weight, and volume on oven-dry, a i r - d r y or green c o n d i t i o n . The most common methods u t i l i z e d t o measure small wood samples r e l a t i v e d e n s i t y a re g r a v i m e t r i c a n a l y s e s (Smith, 1954; I f j u , 1969; E l l i o t t , 1970) and x-ray d e n s i t o m e t r i c techniques (Parker et aj_. , 1973; Parker and Jo z s a , 1973). The l a t t e r method i s p r e f e r r e d because i t e a s i l y p r o v i d e s a continuous readout o f i n t r a - r i n g and i n t e i — r i n g components o f c r o s s - s e c t i o n a l wood c o r e s , such as earlywood, latewood and t o t a l growth increment widths and r e l a t i v e d e n s i t i e s . R e l a t i v e d e n s i t y o f a g i v e n growth increment i n c r e a s e s as the p r o p o r t i o n o f latewood i n c r e a s e s and the t r a c h e i d s become s m a l l e r and t h i c k e r - w a l l e d (Zobel and T a l b e r t , 1984). In D o u g l a s - f i r , the average growth increment r e l a t i v e d e n s i t y i s c o n t r o l l e d mainly by the p r o p o r t i o n o f latewood t r a c h e i d s , due t o the f a c t t h a t the r e l a t i v e d e n s i t y o f such t r a c h e i d s i s between two and t h r e e times higher than t h a t o f earlywood t r a c h e i d s ( I f j u and Kennedy, 1962; I f j u e t a ] . . , 1965). 20 In some s p e c i e s , the v a r i a t i o n s i n r e l a t i v e d e n s i t y are p r i m a r i l y c o r r e l a t e d t o the number o f growth increments from th e p i t h (age) r a t h e r than t o the growth r a t e . T h i s means t h a t the growth r a t e s and r e l a t i v e d e n s i t i e s o f t r e e s o f comparable environment, s p e c i e s , age and h e i g h t a r e v i r t u a l l y independent t r a i t s (Turnbul1, 1937; Rendle and P h i l l i p s , 1957). In the case o f D o u g l a s - f i r and many p i n e s p e c i e s , s e v e r a l s t u d i e s have s u b s t a n t i a t e d t h i s t r e n d (Goggans, 1961; Smith et aj_., 1966; McKimmy, 1966; Kennedy and Warren, 1969; De Guth, 1980; Pearson and GiImore, 1980; B a r r e t t and K e l l o g g , 1984; Pearson and Ross, 1984). In spruce and f i r , however, f a s t growth r a t e i s u s u a l l y a s s o c i a t e d with low r e l a t i v e d e n s i t y (Hale and Fenson, 1931; Hale and P r i n c e , 1940; A l d r i d g e and Hudson, 1959; Chang and Kennedy, 1967). Within t r e e r e l a t i v e d e n s i t y v a r i a t i o n can be a s s e s s e d i n a h o r i z o n t a l , v e r t i c a l or diagonal c l a s s i f i c a t i o n scheme (Duff and Nolan, 1953; Forward and Nolan, 1964). The h o r i z o n t a l scheme i s the most s t u d i e d and r e p r e s e n t s t h e h o r i z o n t a l l y or d i a m e t r i c a l l y arranged sequence o f growth increments from p i t h t o bark. The v e r t i c a l scheme re p r e s e n t s the v e r t i c a l l y arranged sequence o f growth increments a t the same cambial age. F i n a l l y , the diagonal scheme r e p r e s e n t s the d i a g o n a l l y arranged sequence o f growth increments f o r the same cale n d a r year. 21 Ac c o r d i n g t o the h o r i z o n t a l r e l a t i v e d e n s i t y v a r i a t i o n , the j u v e n i l e wood r e l a t i v e d e n s i t y can be lower than, hi g h e r than or approximately the same as t h a t o f mature wood, depending upon s p e c i e s . The most common t r e n d found i s a low j u v e n i l e wood r e l a t i v e d e n s i t y which g r a d u a l l y i n c r e a s e s from the p i t h t o mature wood, where i t s t a b i l i z e s . T h i s t r e n d was d e s c r i b e d by Loo et al_. (1985) f o r l o b l o l l y p i n e , by F o e l k e l e t al_. (1976) f o r s l a s h p i n e , by Bower et aJL- (1976) f o r Caribbean p i n e , by H a r r i s (1969a) f o r r a d i a t a p i n e , by Paul (1950), Wellwood (1952), L i t t l e f o r d (1961), H a r r i s (1969a), Cown (1976), Gerhards (1979), and by B a r r e t t and K e l l o g g (1984) f o r D o u g l a s - f i r . The j u v e n i l e wood r e l a t i v e d e n s i t y i n D o u g l a s - f i r was a l s o found h i g h e s t near the p i t h , d e c r e a s i n g r a p i d l y i n the f i r s t growth increments from the p i t h , then i n c r e a s i n g outward t o the mature wood (Chalk, 1953; H a r r i s and Orman, 1958; Kennedy and Warren, 1969; Cown, 1976; Megraw and Nearn, 1972; Jo z s a and K e l l o g g , 1986). The j u v e n i l e wood r e l a t i v e d e n s i t y was found t o be higher than t h a t o f mature wood by B o u t e l j e (1968) f o r Norway spruce (P i c e a abi es (L.) K a r s t . ) , by T a y l o r e t a l . (1982), and Wang and Micko (1984) f o r white spruce, by Jozsa and K e l l o g g (1986) f o r i n t e r i o r white spruce or i n t e r i o r Engelmann spruce (Pi cea enge1mann i i P a r r y ) , by Wood and Bryan (1960) f o r S i t k a spruce (Pi cea s i tchens i s 22 (Bong.) C a r r . ) , by Polge (1964), Well wood and Jurazs (1968), and Jozsa and K e l l o g g (1986) f o r western redcedar, and by Well wood and Smith (1962), Krahmer (1966), and Jo z s a and K e l l o g g (1986) f o r western hemlock (Tsuga h e t e r o p h y l l a (Raf.) S a r g . ) . L i t t l e or no h o r i z o n t a l r e l a t i v e d e n s i t y v a r i a t i o n between j u v e n i l e and mature wood was found by H a r r i s (1969a) f o r balsam f i r (Abies balsamea (L.) M i l l . ) and Norway spruce, and by Jozsa and K e l l o g g (1986) f o r lodgepole pine (Pinus c o n t o r t a Dougl.) and i n t e r i o r D o u g l a s - f i r (Pseudotsuga menz i es i i v a r . g l a u c a (Beissn.) F r a n c o ) . C o n s i d e r i n g the v e r t i c a l r e l a t i v e d e n s i t y v a r i a t i o n scheme, the j u v e n i l e (crown-formed) wood r e l a t i v e d e n s i t y was r e p o r t e d as s i g n i f i c a n t l y lower than t h a t f o r mature (stem-formed) wood by Cooper (1960) and Brunden (1964) f o r red pine (Pinus r e s i n o s a A i t . ) . Well wood (1952, 1960) s t u d y i n g the d e n s i t y v a r i a t i o n o f 130 D o u g l a s - f i r and 39 western hemlock, sampled a t stump h e i g h t , o n e - t h i r d t o t a l h e i g h t and the top o f the merchantable stem, found t h a t r e l a t i v e d e n s i t y decreased s i g n i f i c a n t l y with i n c r e a s e d h e i g h t o f t h e t r e e s . In c o n t r a s t , Polge (1964) and Wei 1 wood and Jurazs (1968) found t h a t the crown-formed wood r e l a t i v e d e n s i t y was higher than t h a t o f the stem-formed wood i n western redcedar. 23 A s l i g h t v e r t i c a l r e l a t i v e d e n s i t y v a r i a t i o n , probably a s s o c i a t e d with the presence o f compression wood i n the growth increments c l o s e t o the p i t h , has been found w i t h i n the j u v e n i l e wood core o f some s p e c i e s . For i n s t a n c e , a small d e n s i t y i n c r e a s e i n the t e r m i n a l p o r t i o n o f the l i v e crown was r e p o r t e d by H a r r i s and Orman (1958) and K e l l o g g and Kennedy (1986) f o r D o u g l a s - f i r , by Zobel et aj_. (1959) f o r l o b l o l l y p i n e and s l a s h p i n e , and by Krahmer (1966) f o r western hemlock. F i n a l l y , t he diagonal r e l a t i v e d e n s i t y v a r i a t i o n scheme i s c h a r a c t e r i z e d by an i n i t i a l decrease from t h e apex t o approximately the l i m i t o f the l i v e crown, f o l l o w e d by an i n c r e a s e toward the stem base. T h i s t r e n d can be seen from t h e data o f H a r r i s and Orman (1958) on D o u g l a s - f i r and Richardson (1961) on C o r s i c a n pine (Pinus n i g r a v a r . mar i t i m a ( A l t . ) M e l v i l l e ) . The most commonly found r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n s i n D o u g l a s - f i r a r e summarized below. 1. R e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n s a r e p r i m a r i l y r e l a t e d t o t h e p r o p o r t i o n o f the latewood t r a c h e i d s and t o the number o f growth increments from the p i t h . 2. R e l a t i v e d e n s i t y i n j u v e n i l e wood i s high near the p i t h and i n the t e r m i n a l p o r t i o n o f the l i v e crown, decreases r a p i d l y i n the 24 f i r s t growth increments from the p i t h and in c r e a s e s outward toward the mature wood, where i t s t a b i l i z e s . 3. In i n t e r i o r D o u g l a s - f i r t h e r e i s a s l i g h t or no r e l a t i v e d e n s i t y v a r i a t i o n from j u v e n i l e t o mature wood. 2.2.2.2 Other P r o p e r t i e s The p h y s i c a l p r o p e r t i e s o f s t r e n g t h , e l a s t i c i t y and moisture content, i n combination with the presence o f knots and growth r e l a t e d d e f e c t s , such as compression wood and s p i r a l g r a i n , determine the s u i t a b i l i t y o f j u v e n i l e and mature wood f o r s e v e r a l end uses. The v a r i a t i o n s o f the s t r e n g t h and e l a s t i c p r o p e r t i e s o f j u v e n i l e and mature wood are mainly c o r r e l a t e d t o the r e s p e c t i v e v a r i a t i o n s i n r e l a t i v e d e n s i t y . In g e n e r a l , the s t r e n g t h and e l a s t i c i t y o f dimension lumber manufactured completely from, or c o n t a i n i n g a hig h percentage o f , j u v e n i l e wood, has been found t o be l e s s than the s t r e n g t h and e l a s t i c i t y o f mature wood. T h i s t r e n d was r e p o r t e d by Boone and Chudnoff (1972) and Bower et a l . (1976) f o r Caribbean p i n e , by Pearson and Gilmore (1971, 1980) and Pearson and Ross (1984) f o r l o b l o l l y p i n e , and by Wangaard and Zumwalt (1949), L i t t l e f o r d (1961), 25 Gerhards (1979), B a r r e t t and K e l l o g g (1984) and Se n f t et a l . (1986) f o r D o u g l a s - f i r . J u v e n i l e wood moisture content has been r e p o r t e d t o be higher than t h a t o f mature wood by Zobel e t a]_. (1968) and Zobel et aj_. (1972) f o r l o b l o l l y and s l a s h p i n e , and by B r i t t (1970) f o r l o b l o l l y p i n e . Compression wood i n the j u v e n i l e wood was r e p o r t e d by Boone and Chudnoff (1972) f o r Caribbean p i n e , by C r i s t e t a 1. (1977) f o r jack p i n e (Pinus banksiana Lamb.) and ea s t e r n l a r c h , and by Zobel and K e l l i s o n (1972) and Zobel et a l . (1972) f o r l o b l o l l y and s l a s h p i n e s . In D o u g l a s - f i r , the p o s s i b l e presence o f compression wood i n j u v e n i l e wood has been suggested as the p r i n c i p l e cause o f the high d e n s i t y values observed i n the growth increments c l o s e t o the p i t h (Chalk, 1953; H a r r i s and Orman, 1958; Kennedy and Warren, 1969; K e l l o g g and Kennedy, 1986). High s p i r a l g r a i n a n g l e s i n J u v e n i l e wood were r e p o r t e d by H a r r i s (1969b) f o r r a d i a t a p i n e and by Zobel et a l . (1972) f o r s l a s h and l o b l o l l y p i n e s . In D o u g l a s - f i r , N o r t h c o t t (1957), E l l i o t t (1958) and Woodfin (1969) observed t h a t the most f r e q u e n t s p i r a l p a t t e r n was i n the l e f t d i r e c t i o n near the p i t h , with the angle i n c r e a s i n g i n the f i r s t formed growth increments i n the j u v e n i l e wood, and then changing g r a d u a l l y from l e f t t o r i g h t s p i r a l f t y as the t r e e age i n c r e a s e d . 26 2.2.3 J u v e n i l e - Mature Wood T r a n s i t i o n Determination Determination o f the t r a n s i t i o n zone from j u v e n i l e t o mature wood i s c r i t i c a l f o r s e t t i n g r e l a t i v e p r o p o r t i o n s , and important i n d e f i n i t i o n o f wood q u a l i t y and timber val u e . T h i s d e t e r m i n a t i o n can be d i f f i c u l t , however, because as j u v e n i l e wood matures, the changes i n i t s p r o p e r t i e s a r e gradual and o f t e n e r r a t i c . The c h a r a c t e r i s t i c s o f change d i f f e r a c c o r d i n g t o sp e c i e s and wood p r o p e r t i e s s e l e c t e d f o r a n a l y s i s . For example, the mechanical p r o p e r t i e s and r e l a t i v e d e n s i t y o f wood g e n e r a l l y i n d i c a t e m a t u r i t y e a r l i e r than t r a c h e i d length and m i c r o f i b r i l angle (Bendtsen, 1978; Megraw, 1985; Bendtsen and S e n f t , 1986). Some s p e c i e s o f spruce (Pi cea spp.), f i r (Abi es spp.) and c y p r e s s (Cuppressus spp.) a r e c h a r a c t e r i z e d by an i n d i s t i n c t j u v e n i l e - mature wood t r a n s i t i o n zone. T h e r e f o r e , the d i f f e r e n c e s i n p r o p e r t i e s between j u v e n i l e and mature wood are d i f f i c u l t t o observe (Z o b e l , 1984). In c o n t r a s t , D o u g l a s - f i r and most hard p i n e s , such as l o b l o l l y p i n e , s l a s h p i n e and Caribbean p i n e , show a more d i s t i n c t j u v e n i l e - mature wood t r a n s i t i o n zone. 27 Several s u b j e c t i v e and o b j e c t i v e methods have been u t i l i z e d t o d e f i n e the t r a n s i t i o n zone between j u v e n i l e and mature wood. 2.2.3.1 S u b j e c t i v e Methods The f i r s t , and perhaps the most g e n e r a l , method o f det e r m i n i n g the j u v e n i l e - mature wood t r a n s i t i o n zone from the s u b j e c t i v e viewpoint i s v i s u a l examination o f stem c r o s s s e c t i o n s or increments c o r e s . For i n s t a n c e , Zobel et a l . (1959) d e f i n e d the t r a n s i t i o n zone f o r s l a s h p i n e as the f i r s t f i v e t o e i g h t growth increments from the p i t h , and f o r l o b l o l l y pine as the f i r s t seven t o 11 growth increments from the p i t h , based on the d u l l and l i f e l e s s appearance o f j u v e n i l e wood stem c r o s s s e c t i o n samples when dr i ed. Yang e t a±. (1986) d e f i n e d the t r a n s i t i o n zone i n e a s t e r n l a r c h ( L a r i x 1 a r i c i n a (Du Roi) K. Koch) as the f i r s t f o u r t o 45 growth increments from the p i t h , depending on the sampling h e i g h t . The t r a n s i t i o n zone was v i s u a l l y determined i n two cm wide d i a m e t r i c s t r i p wood samples based on the l i g h t c o l o u r and width o f growth increments i n the j u v e n i l e zone. 28 Other authors have d e f i n e d the t r a n s i t i o n zone by comparing the wood p r o p e r t i e s o f young t r e e s with the wood p r o p e r t i e s o f o l d t r e e s . Zobel and K e l l i s o n (1972) used t h i s method when d e f i n i n g the t r a n s i t i o n zone as the f i r s t t e n growth increments from t h e p i t h , by comparing the wood p r o p e r t i e s o f 11-year-old j u v e n i l e t o 30-year-old mature l o b l o l l y p i n e t r e e s . Boone and Chudnoff (1972) and Bower et a l . (1976) u t i l i z e d the same approach when comparing p l a n t a t i o n grown and f o r e s t grown Caribbean p i n e t r e e s . The t r a n s i t i o n zone can a l s o be d e f i n e d by comparing the wood p r o p e r t i e s o f j u v e n i l e (crown-formed) wood t o mature (stem-formed) wood. The age a t the base o f the l i v e crown can then be i d e n t i f i e d as the t r a n s i t i o n age between j u v e n i l e and mature wood. Brunden (1964), s t u d y i n g r e d pin e , found t h a t the length and r e l a t i v e d e n s i t y o f stem-formed t r a c h e i d s were s i g n i f i c a n t l y h i g h e r than those from crown-formed wood. He d i d not, however, c o n s i d e r t h e age a t the base o f the l i v e crown. Cooper (1960) found t h a t r e d pi n e stem-formed wood r e l a t i v e d e n s i t y was s i g n i f i c a n t l y higher than t h a t o f the crown-formed wood. He i d e n t i f i e d t he age a t the base o f the l i v e crown as approximately 20 y e a r s . F i n a l l y , t he j u v e n i l e - mature wood t r a n s i t i o n zone has been determined on the b a s i s o f changes i n c e r t a i n anatomical or p h y s i c a l wood p r o p e r t i e s between the c l o s e s t 29 and f a r t h e s t growth increments from the p i t h . The t r a n s i t i o n zone i s d e f i n e d as the l o c a t i o n where the v a l u e s o f these p r o p e r t i e s begin t o remain c o n s t a n t . In southern and t r o p i c a l p i n e s , the t r a n s i t i o n zone ranges from s i x t o 15 growth increments from the p i t h (Zobel and McElwee, 1958; Pearson and G i l more, 1980; Bendtsen, 1978; Z o b e l , 1984; S e n f t e t a l . , 1985). In Japanese l a r c h ( L a r i x 1epto1ep i s ( S i e b . and Zucc.) Endl.) and white spruce, the t r a n s i t i o n zone has been r e p o r t e d as the f i r s t t e n growth increments from the p i t h by Isebrands and Hunt (1975) and by T a y l o r et aj_. (1982). In D o u g l a s - f i r , the t r a n s i t i o n zone has been r e p o r t e d as the f i r s t 15 t o 20 growth increments from t h e p i t h (Wellwood and Smith, 1962; McKimmy, 1966; E r i c k s o n and Arima, 1974; E r i c k s o n and H a r r i s o n , 1974; McKimmy and Campbell, 1982; B a r r e t t and K e l l o g g , 1984; S e n f t et a l • , 1985; Jackson and Megraw, 1986; S e n f t e t aj_. , 1986; J o z s a and K e l l o g g , 1986). 2.2.3.2 O b j e c t i v e Methods Rece n t l y , some r e s e a r c h e r s have u t i l i z e d more o b j e c t i v e methods t o d e f i n e the zone o f t r a n s i t i o n between j u v e n i l e and mature wood. For i n s t a n c e , Shiokura (1984) used a l o g a r i t h m i c r e g r e s s i o n equation t o r e l a t e t r a c h e i d 30 length t o the number o f growth increments from the p i t h (age). The t r a n s i t i o n zone was d e f i n e d when a one percent t r a c h e i d length d i f f e r e n c e was recorded between two c o n s e c u t i v e growth increments. The t r a n s i t i o n ages at d i f f e r e n t h e i g h t s were 11 t o 19 on Japanese l a r c h , 14 t o 18 on S a k h a l i n f i r (Abi es sacha1i nens i s Mast.) and on Hondo spruce (Pi cea Jezoens i s ( S i e b . and Zucc.) Carr.) and 20 t o 22 on Japanese red cedar (Cryptomeria Japonica (L.F.) Don). Yang et al_. (1986) u t i l i z e d two simple l i n e a r r e g r e s s i o n models t o r e l a t e t r a c h e i d length t o number o f growth increments from the p i t h . The f i r s t model was f i t t e d i n the j u v e n i l e wood zone, where the length o f t r a c h e i d s i n c r e a s e d , and the second was f i t t e d i n the mature wood zone, where the length o f the t r a c h e i d s remained c o n s t a n t . The t r a n s i t i o n zone, which was determined as the age a t which the j u v e n i l e and mature r e g r e s s i o n models i n t e r s e c t e d , was found t o be from t e n t o 44, depending on t r e e h e i g h t . Loo et aj_. (1985), s t u d y i n g the g e n e t i c v a r i a t i o n i n the time o f t r a n s i t i o n from j u v e n i l e t o mature wood in l o b l o l l y p i n e , u t i l i z e d a combination o f t h r e e methods t o d e f i n e the t r a n s i t i o n age, and c o n s i d e r e d the p r o p e r t i e s o f s p e c i f i c g r a v i t y and t r a c h e i d length. The f i r s t method i n v o l v e d f i t t i n g two simple l i n e a r r e g r e s s i o n models t o t h e data, which were p l o t t e d as f u n c t i o n s o f age. The age o f 31 the t r a n s i t i o n was estimated as the age a t which the second model (mature wood) showed the best f i t , determined by the s m a l l e s t r e s i d u a l sum o f squares. The second method was used when the best f i t t e d mature wood model, u s i n g the f i r s t method, showed a n e g a t i v e s l o p e . In t h i s case, the slo p e o f the mature wood model was h e l d constant a t z e r o , assuming t h a t the mature wood values f l u c t u a t e around the constant mean. The t h i r d method was a v i s u a l examination, used when the data p o i n t s d i d not conform t o the former two p a t t e r n s o f v a r i a t i o n . The mean ages o f t r a n s i t i o n were found t o be 11.45 and 10.30 years f o r s p e c i f i c g r a v i t y and t r a c h e i d l e n g t h , r e s p e c t i v e l y . Bendtsen and Se n f t (1986) a p p l i e d t h r e e methods t o both i n d i v i d u a l t r e e and average v a l u e s o f s t r e n g t h , e l a s t i c i t y , s p e c i f i c g r a v i t y , c e l l length and f i b r i l a n g l e t o determine the t r a n s i t i o n ages f o r l o b l o l l y p i n e and cottonwood (Popu1 us de1 t o i d e s B a r t r . ) . The methods used were segmented r e g r e s s i o n a n a l y s i s , d i s c r i m i n a t e a n a l y s i s , and a n a l y s i s o f s l o p e . None o f these methods produced a c o n s i s t e n t demarcation between j u v e n i l e and mature wood because o f the larg e v a r i a b i l i t y among values from t r e e t o t r e e and year t o year. T h e r e f o r e , v i s u a l i n t e r p r e t a t i o n s o f the data and data p l o t s were used t o determine the t r a n s i t i o n ages, which were, depending on the p r o p e r t y a n a l y z e d , 12 t o 18 f o r l o b l o l l y pine and 17 t o 18 f o r cottonwood. 32 In c o n c l u s i o n , i t can be s a i d t h a t the age o f the j u v e n i l e - mature wood t r a n s i t i o n ranges from f i v e t o 18 years in southern and t r o p i c a l p i n e s , from 15 t o 20 years in D o u g l a s - f i r , and from f o u r t o 44 years i n the r e s t o f the s p e c i e s d e s c r i b e d , depending on the sampling h e i g h t and wood p r o p e r t y analyzed. In some s p e c i e s o f spruce, f i r and cy p r e s s , the j u v e n i l e - mature wood t r a n s i t i o n zone i s not c l e a r l y d e f i n e d . 33 3.0 MATERIALS AND METHODS In o r d e r t o t e s t the p r o j e c t h y p o t h e s i s , 13 unpruned, two pruned second-growth, and two unpruned plantation-grown c o a s t a l D o u g l a s - f i r t r e e s were sampled from nine stands as fo11ows. S i x second-growth stands were s e l e c t e d on the west and east c o a s t s o f Vancouver I s l a n d , B r i t i s h Columbia as a p a r t o f the D o u g l a s - f i r Task Force P r o j e c t ( K e l l o g g , 1986). The stands were approximately 50 years o l d and growing on s i t e s o f medium t o good p r o d u c t i v i t y . Ten dominant and codominant D o u g l a s - f i r t r e e s o f uniform growth r a t e (growth increments o f approximately f o u r t o f i v e mm per year) were s e l e c t e d from each stand by the Task Force f o r b a s i c wood pr o p e r t y s t u d i e s . The two f e l l e d t r e e s per stand with the most i n t a c t crowns were s e l e c t e d f o r the present study o f the t r a n s i t i o n from j u v e n i l e wood t o mature wood. F i v e a d d i t i o n a l t r e e s were s e l e c t e d t o extend sampling t o pruned stands, and t o s i t e s o f d i f f e r e n t p r o d u c t i v i t y . One t r e e was measured i n each o f two 37-year-old p l a n t a t i o n s growing on s o i l o f high (marine c l a y ) and low (gravel outwash) p r o d u c t i v i t y l o c a t e d west o f Campbell R i v e r . One unpruned 21 y e a i — o l d t r e e , and two pruned t r e e s o f 51 and 45 years o f age were sampled from the U n i v e r s i t y o f B r i t i s h Columbia 34 Research F o r e s t a t Haney. The pruned t r e e s were approximately 15 cm D.B.H. and approximately 14 m t a l l when the lower o n e - t h i r d o f the l i v e crown was removed t o a height o f f o u r t o f i v e metres in 1954. The l o c a t i o n o f the stands i s shown in F i g u r e 1, while stand c h a r a c t e r i s t i c s a r e g i v e n i n Table 1. Sample t r e e data a r e shown i n Table 2. 3.1 E x t e r n a l Tree C h a r a c t e r i s t i c s The e x t e r n a l t r e e c h a r a c t e r i s t i c s were c a t e g o r i z e d as stem and crown r e s p e c t i v e l y . The f o l l o w i n g stem measurements were made and recorded: 1. Age a t stump; 2. T o t a l t r e e h e i g h t ; 3. Internodal d i s t a n c e s over the length o f the stem; 4. Height t o base o f l i v e crown ( d i s t a n c e from the ground t o the lowest whorl which has t h r e e or more l i v e branches); and 5. Inside and o u t s i d e bark diameters o f f i v e c r o s s - s e c t i o n a l d i s c s , e i g h t t o 16 cm t h i c k , cut from b r e a s t h e i g h t , and p o s i t i o n s 20, 40, 60 and 80 percent o f t o t a l t r e e h e i g h t . 35 These measurements were taken t o estimate the curve r e p r e s e n t i n g cumulative h e i g h t growth over number o f growth increments from the p i t h f o r each t r e e . The c r o s s - s e c t i o n a l d i s c s were taken t o F o r i n t e k Canada C o r p o r a t i o n ' s x-ray densitometry l a b o r a t o r y i n Vancouver f o r f u r t h e r a n a l y s i s . To study the a c t u a l crown c h a r a c t e r i s t i c s , crown cover, l i v e branches and h e i g h t t o base o f the l i v e crown were measured as f o l l o w s . The crown cover, or ground a r e a covered by the v e r t i c a l p r o j e c t i o n o f each crown, was measured u s i n g a m e t r i c tape and a Suunto c l i n o m e t e r with a 90 degree s c a l e (Husch et aj_. , 1982). An average crown r a d i u s was estimated from s i x t o seven crown r a d i i measurements taken every 45 degrees around the perimeter o f the crown and towards competing t r e e s (Table 3 ). Length and h e i g h t p o s i t i o n o f two l i v e branches o f s i m i l a r diameter from o p p o s i t e s i d e s o f every second whorl were measured from each t r e e . The h e i g h t t o base o f l i v e crown was determined by measuring the d i s t a n c e from the ground t o t h e lowest whorl which had t h r e e or more l i v e branches. In a d d i t i o n , an average crown h e i g h t was c a l c u l a t e d as a f u n c t i o n o f the average crown r a d i u s , which r e p r e s e n t e d the maximum length o f the branches l o c a t e d a t the widest p a r t o f the crown. Average crown he i g h t was estimated i n order t o r e l a t e the r e s u l t s o f t h i s p r o j e c t t o 36 the M i n i s t r y o f F o r e s t s and Lands Tree and Stand Simulator Model (TASS) ( M i t c h e l l , 1975, 1980; M i t c h e l l and Cameron, 1985). The procedure f o r e s t i m a t i n g average crown h e i g h t i s summarized in Appendix 1 and the r e s u l t s a r e c o n t a i n e d i n Tab 1e 3. To study the development o f the crown over time, two r e p r e s e n t a t i v e dead branches or branch stubs were c o l l e c t e d from every second or t h i r d branch whorl. Each branch was examined t o determine the number o f growth increments a t the base, which r e p r e s e n t e d the age a t which the branch stopped producing growth increments. D i s c s o f one cm t h i c k n e s s were cut from each branch base, l a b e l l e d and sanded. The growth increments i n each branch d i s c were counted and recorded u s i n g a low power s t e r e o s c o p i c microscope. The number o f growth increments i n each branch d i s c and the c o r r e s p o n d i n g whorl h e i g h t p o s i t i o n were u t i l i z e d t o determine the approximate p o s i t i o n o f the base o f the l i v e crown a t younger ages. An example o f t h i s d e t e r m i n a t i o n i s shown i n Appendix 2. 3.2 I n t e r n a l Tree C h a r a c t e r i s t i c s To study the i n t e r n a l t r e e c h a r a c t e r i s t i c s , x-ray d e n s i t o m e t r i c techniques were u t i l i z e d t o determine growth increment r e l a t i v e d e n s i t y d a t a . L i n e a r r e g r e s s i o n 37 techniques were u t i l i z e d t o estimate the j u v e n i l e - mature wood t r a n s i t i o n age from the data. 3.2.1 X-Ray D e n s i t o m e t r i c Analyses For the x-ray d e n s i t o m e t r i c e v a l u a t i o n , a t o t a l o f 85 c r o s s - s e c t i o n a l d i s c s (17 t r e e s , f i v e sample h e i g h t s ) o f e i g h t t o 16 cm t h i c k , were sampled. On each d i s c , two average r a d i i s e c t i o n s a t l e a s t 90 degrees a p a r t were measured and l a b e l l e d , a v o i d i n g knots, r e s i n pockets and compression wood. The average r a d i i were f i r s t cut i n t o s t r i p s o f one cm t h i c k and 10 cm wide. They were then r e - c u t i n t o s m a l l e r sample s t r i p s , f i v e mm wide in the t a n g e n t i a l d i r e c t i o n and s i x mm t h i c k a l o n g the g r a i n , resembling increment c o r e s . The wood sample s t r i p s were u t i l i z e d f o r x-ray densitometr1c a n a l y s i s f o l l o w i n g the procedures e x p l a i n e d i n d e t a i l by Parker and Jozsa (1973) and by Parker et aj_. (1973, 1980). A summary o f these procedures i s presented i n Appendix 3. A t o t a l o f 170 wood core r a d i i were scanned u s i n g the above procedure. The r e l a t i v e d e n s i t y values were expressed on an oven-dry volume and weight b a s i s . Annual p i t h t o bark r e l a t i v e d e n s i t y p r o f i l e s (average r e l a t i v e d e n s i t y o f two core r a d i i growth increments per sample s e c t i o n ) were p l o t t e d t o determine the annual growth 38 increment r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n s as a f u n c t i o n o f number o f growth increments from the p i t h and height p o s i t i o n on the stem o f each sample t r e e , as shown i n F i g u r e 2, f o r Sample Tree 1A5. 3.2.2 J u v e n i l e - Mature Wood T r a n s i t i o n Determination A f t e r p l o t t i n g the r e l a t i v e d e n s i t y p r o f i l e s o f each sample s e c t i o n , a v i s u a l examination was done t o d e t e c t t h e lowest r e l a t i v e d e n s i t y value and a p o s s i b l e j u v e n i l e - mature wood zone based on the shape o f the p r o f i l e . Two c a t e g o r i e s o f p r o f i l e s were i d e n t i f i e d . The f i r s t c a t e g o r y i n c l u d e d the r e l a t i v e d e n s i t y p r o f i l e s which showed f a i r l y constant r e l a t i v e d e n s i t y v a l u e s from the p i t h t o bark, without a c l e a r d e f i n i t i o n o f t r a n s i t i o n zone. In t h i s case, a simple l i n e a r r e g r e s s i o n model was f i t t e d t o each p r o f i l e , s t a r t i n g from the lowest r e l a t i v e d e n s i t y value outwards, and i t was assumed t h a t the p r o f i l e r e p r e s e n t e d j u v e n i l e wood e n t i r e l y . The second category i n c l u d e d the p r o f i l e s t h a t showed an i n i t i a l decrease in r e l a t i v e d e n s i t y i n the f i r s t growth increments from the p i t h , f o l l o w e d by a gradual l i n e a r i n c r e a s e f o r a c e r t a i n number o f increments, then a f i n a l l e v e l l i n g o f f outwards. T h i s r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n i n d i c a t e d the p o s s i b l e evidence o f a t r a n s i t i o n 39 zone i n the p r o f i l e . To determine such t r a n s i t i o n zone, a segmented r e g r e s s i o n a n a l y s i s o f each r e l a t i v e d e n s i t y p r o f i l e was done as d e s c r i b e d below (Hudson, 1966; Draper and Smith, 1981). 1. A segmented r e g r e s s i o n model, which combines two l i n e a r segments, was f i t t e d t o each o f the p r o f i l e s s t a r t i n g a t the lowest r e l a t i v e d e n s i t y v a l u e . The model u t i l i z e d was: y = b Q + b j b 2 + b 3 ( x - b 2> where: y = p r e d i c t e d v alue ( r e l a t i v e d e n s i t y ) bg = i n t e r c e p t o f f i r s t l i n e segment bj = s l o p e o f f i r s t l i n e segment t>2 - t r a n s i t i o n age estimate bg = s l o p e o f second l i n e segment x = independent v a r i a b l e (number o f growth increments from the p i t h ) 2. The b e s t f i t t e d model was determined by m i n i m i z i n g the t o t a l r e s i d u a l sum o f squares o f every p o s s i b l e d i v i s i o n o f the p o i n t s between the f i r s t and the second segment. T h i s method i s c a l l e d the Least Squares L i n e o f Best F i t and i s g i v e n by: 40 n n I e 2 f = I ( y f - y, ) 2 i = 1 i = l where: n 2 £ e j = r e s i d u a l sum o f squares i = 1 y^ = observed values ( r e l a t i v e d e n s i t y ) A y. = p r e d i c t e d values ( r e l a t i v e d e n s i t y ) The d i v i s i o n and s e t o f estimates t h a t gave r i s e t o the s m a l l e s t r e s i d u a l sum o f squares was s e l e c t e d . T h i s was done by means o f a F o r t r a n program which i n c l u d e d n o n - l i n e a r o p t i m i z a t i o n r o u t i n e s (Appendix 4 ) . 3. The c o n s t r a i n t s o f t h i s procedure were t h a t the f i r s t segment must s t a r t a t the lowest r e l a t i v e d e n s i t y data p o i n t and t h a t the i n t e r s e c t i o n p o i n t between the two segments must be between two c o n s e c u t i v e growth increments t h a t s p l i t the data s e t . 4. The p o i n t o f i n t e r s e c t i o n between the two l i n e a r segments was i d e n t i f i e d t o determine the number o f growth increments (age) a t which the t r a n s i t i o n from j u v e n i l e t o mature wood o c c u r r e d . 41 To v e r i f y the need f o r a segmented r e g r e s s i o n a n a l y s i s , a s t a t i s t i c a l "F" t e s t was done, c a l c u l a t i n g the r a t i o between the mean sum o f squares r e s i d u a l value o f a simple l i n e a r r e g r e s s i o n model and t h a t o f a segmented r e g r e s s i o n model, both f i t t e d t o the same p r o f i l e ( F i g u r e s 3a and 3b). When the "F" r a t i o s c a l c u l a t e d were g r e a t e r than the "F" values t a b u l a t e d by Pearson and H a r t l e y (1954) the segmented r e g r e s s i o n model was chosen t o determine the j u v e n i l e - mature wood t r a n s i t i o n zone. When the "F" r a t i o s c a l c u l a t e d were lower than the "F" values t a b u l a t e d , the simple r e g r e s s i o n model was chosen and the j u v e n i l e - mature wood t r a n s i t i o n zone c o u l d not be determined. In t h i s case, i t was assumed t h a t the r e l a t i v e d e n s i t y p r o f i l e r e p r e s e n t e d j u v e n i l e wood ent i r e 1y. The d e t e r m i n a t i o n s o f the t r a n s i t i o n zone by the segmented r e g r e s s i o n a n a l y s i s were checked a g a i n s t the co r r e s p o n d i n g p r o f i l e t o ensure t h a t the r e g r e s s i o n model used was the most reasonable c h o i c e with r e s p e c t t o the da t a . 42 A f t e r d e t e r m i n a t i o n o f the j u v e n i l e - mature wood t r a n s i t i o n age f o r each r e l a t i v e d e n s i t y p r o f i l e , r e l a t i o n s h i p s between number o f growth increments from the p i t h and t r e e height p o s i t i o n o f both t r a n s i t i o n zone and base o f the l i v e crown were e s t a b l i s h e d . These w i t h i n t r e e and between t r e e r e l a t i o n s h i p s were u t i l i z e d t o t e s t the p r o j e c t h y p o t h e s i s , and can be used t o f u r t h e r extend the TASS model ( M i t c h e l l , 1975, 1980; M i t c h e l l and Cameron, 1985) f o r p r e d i c t i n g the volume o f both j u v e n i l e and mature wood. In a d d i t i o n , average j u v e n i l e and mature annual growth Increment r e l a t i v e d e n s i t i e s were determined t o observe the w i t h i n t r e e and between t r e e r e l a t i v e d e n s i t y var i a t i o n s . 4.0 RESULTS AND DISCUSSION Tabl e 2 g i v e s a summary o f sample t r e e c h a r a c t e r i s t i c s . The plantation-grown and second-growth t r e e s were dominant and codominant with ages a t b r e a s t h e i g h t r a n g i n g from 21 t o 63 y e a r s , diameters a t b r e a s t h e i g h t from 19.8 t o 68.2 cm and t o t a l h e i g h t s from 16.8 t o 44.7 m. These plantation-grown and second-growth t r e e s were a n a l y z e d s e p a r a t e l y from the pruned t r e e s . It must be noted t h a t sample t r e e s were s e l e c t e d from the nine s i t e s without attempting t o a c h i e v e a r e p r e s e n t a t i o n o f the t o t a l popu1 a t i on. 4.1 X-Ray D e n s i t o m e t r i c Analyses Summaries o f the r e l a t i v e d e n s i t y values o f 15 t r e e s f o r s e c t i o n s sampled a t b r e a s t h e i g h t , 20 p e r c e n t , 40 p e r c e n t , 60 percent and 80 percent o f t o t a l t r e e h e i g h t a r e presented i n Tables 4 t o 8 r e s p e c t i v e l y . For each sample s e c t i o n , r e l a t i v e d e n s i t y i s expressed as t h e mean o f a l l annual growth increment means. P i t h t o bark r e l a t i v e d e n s i t y p r o f i l e s are i l l u s t r a t e d f o r Sample Tree 1A5 i n F i g u r e 2. 44 The general r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n o f a l l s e c t i o n s sampled a t b r e a s t h e i g h t showed an i n i t i a l decrease from the p i t h t o a p o i n t w i t h i n the second through t e n t h growth increments f o l l o w e d by a l i n e a r i n c r e a s e which g r a d u a l l y s t a b i l i z e d outwards over subsequent growth increments from the p i t h . O v e r a l l mean r e l a t i v e d e n s i t y f o r these s e c t i o n s was 0.523, with a maximum o f 0.625 and a minimum o f 0.413. The number o f growth increments v a r i e d from 21 t o 63 (Table 4 ) . At 20 percent o f t o t a l h e i g h t the r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n was s i m i l a r t o t h a t o f a l l s e c t i o n s a t br e a s t h e i g h t . Overal1 mean r e l a t i v e d e n s i t y was 0.485, with a maximum o f 0.589 and a minimum o f 0.389. The number of growth Increments v a r i e d from 17 t o 53 and sample h e i g h t from 3.3 t o 8.5m (Tab1e 5 ) . S e c t i o n s sampled a t 40 percent o f t o t a l h e i g h t showed an i n i t i a l d e c l i n e i n r e l a t i v e d e n s i t y from the p i t h t o a p o i n t w i t h i n the t h i r d through f i f t e e n t h growth increments, f o l l o w e d by a gradual i n c r e a s e outwards. In a few cases, a gradual decrease outwards was observed a l s o . O v e r a l l mean r e l a t i v e d e n s i t y f o r these s e c t i o n s was 0.467, with a maximum o f 0.549 and a minimum o f 0.400. The number o f growth increments ranged from 13 t o 45 and sample h e i g h t from 5.1 t o 17.2 m (Tab 1e 6 ) . 45 At 60 percent o f t o t a l h e i g h t t h e r e was an i n i t i a l d e c l i n e i n r e l a t i v e d e n s i t y from the p i t h t o a p o i n t w i t h i n the f o u r t h through f o u r t e e n t h growth increments, f o l l o w e d by a moderate i n c r e a s e outwards. O v e r a l l mean r e l a t i v e d e n s i t y f o r these s e c t i o n s was 0.462 with a maximum o f 0.551 and a minimum o f 0.410. The number o f growth increments v a r i e d from e i g h t t o 31 and sample he i g h t from 9.9 t o 25.8 m (Table 7 ) . The s e c t i o n s sampled a t 80 percent o f t o t a l h e i g h t showed an i n i t i a l decrease i n r e l a t i v e d e n s i t y from t h e p i t h t o a p o i n t w i t h i n the f o u r t h through t w e l f t h growth increments, f o l l o w e d by an i r r e g u l a r and moderate i n c r e a s e outwards. O v e r a l l mean r e l a t i v e d e n s i t y f o r these s e c t i o n s was 0.478 with a maximum o f 0.556 and a minimum o f 0.437. The number o f growth increments v a r i e d from f o u r t o 19 and sample h e i g h t v a r i e d from 13.4 t o 36.1 m (Table 8 ) . From the above r e s u l t s , i t would appear t h a t the h o r i z o n t a l r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n a t the f i v e sample h e i g h t s i s c h a r a c t e r i z e d by an i n i t i a l decrease from the p i t h f o l l o w e d by a gradual i n c r e a s e and s t a b i l i z a t i o n outwards, p a r t i c u l a r l y i n the lower s e c t i o n s ( i . e . b r e a s t h e i g h t , 20 and 40 percent o f t o t a l h e i g h t ) . S i m i l a r h o r i z o n t a l r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n s f o r D o u g l a s - f i r t r e e s were r e p o r t e d by Paul (1950), Wei 1 wood (1952), Chalk (1953), L i t t l e f o r d (1961), H a r r i s (1969a), 46 Kennedy and Warren (1969), Cown (1976), Gerhards (1979), B a r r e t t and K e l l o g g (1984), and by Jozsa and K e l l o g g (1986). The v e r t i c a l o v e r a l l mean r e l a t i v e d e n s i t y f o r s e c t i o n s a t b r e a s t h e i g h t t o 60 percent o f t o t a l h e i g h t (Tables 4 t o 8) showed a decrease from 0.523 t o 0.462, f o l l o w e d by an i n c r e a s e t o 0.478 f o r s e c t i o n s a t 80 percent o f t o t a l h e i g h t . In percentages, the decrease i n r e l a t i v e d e n s i t y from b r e a s t h e i g h t (100 percent) r e p r e s e n t e d approximately seven, 10, 12 and e i g h t percent r e s p e c t i v e l y . T h i s i n d i c a t e s t h a t , i n g e n e r a l , r e l a t i v e d e n s i t y decreases with h e i g h t o f sampling. Q u a l i t a t i v e l y s i m i l a r d e n s i t y v e r t i c a l v a r i a t i o n p a t t e r n s were r e p o r t e d by We11 wood (1952, 1960), and by Megraw (1986). 4.2 J u v e n i l e - Mature Wood T r a n s i t i o n Determination A t o t a l o f 75 r e l a t i v e d e n s i t y p r o f i l e s (15 t r e e s , f i v e sample h e i g h t p o s i t i o n s per t r e e ) were i n v e s t i g a t e d i n order t o d e t e c t t r a n s i t i o n zones between j u v e n i l e and mature wood. The p r o f i l e s were d i v i d e d i n t o two c a t e g o r i e s based on the c o n f i g u r a t i o n o f the data p o i n t s p e r t a i n i n g t o r e l a t i v e d e n s i t y and number o f growth increments from the P i t h . 47 The f i r s t category i n v o l v e d a t o t a l o f 38 p r o f i l e s c h a r a c t e r i z e d by having no c l e a r d e f i n i t i o n o f a j u v e n i l e - mature wood t r a n s i t i o n zone. In g e n e r a l , these p r o f i l e s showed an i n i t i a l decrease i n r e l a t i v e d e n s i t y from the p i t h t o a p o i n t w i t h i n the f o u r t h through t h i r t e e n t h growth increments, f o l l o w e d by a gradual i n c r e a s e , decrease or l e v e l l i n g o f f outwards. To i l l u s t r a t e such t r e n d s , simple l i n e a r r e g r e s s i o n models were f i t t e d t o each p r o f i l e , s t a r t i n g from the lowest r e l a t i v e d e n s i t y value outwards, assuming t h a t they r e p r e s e n t e d j u v e n i l e wood e n t i r e l y (Appendices 5a t o 19a). Table 9 shows a summary o f the d i s t r i b u t i o n and c h a r a c t e r i s t i c s o f these p r o f i l e s among sample h e i g h t s . The average number o f growth increments was 18.42, ra n g i n g from 4 t o 33, and the average s e c t i o n h e i g h t was 20.99 m, ranging from 1.30 t o 36.10 m. It can be seen t h a t about 80 percent o f the cases f o r which no evidence o f j u v e n i l e - mature wood t r a n s i t i o n zone was found were a t s e c t i o n s 60 and 80 percent o f t o t a l h e i g h t . In 15 percent o f the cases no t r a n s i t i o n was found a t 40 percent o f t o t a l h e i g h t . Only i n f i v e percent o f the cases was no t r a n s i t i o n found at s e c t i o n s sampled a t b r e a s t h e i g h t and 20 percent o f t o t a l h e i g h t , c o r r e s p o n d i n g t o the younger sampled t r e e , i . e . RF1 (Appendix 19). 48 From the above, i t i s concluded t h a t mature wood and t h e r e f o r e the j u v e n i l e - mature wood t r a n s i t i o n zone, was not present i n the upper 40 percent o f the stem nor i n lower s e c t i o n s c o n t a i n i n g few growth increments from t h e p i t h ( i . e . 13 t o 3 3 ) . The second category comprises r e l a t i v e d e n s i t y p r o f i l e s which gave evidence o f a t r a n s i t i o n zone. These p r o f i l e s , i n g e n e r a l , showed an i n i t i a l r e l a t i v e d e n s i t y decrease i n the f i r s t growth increments from the p i t h , f o l l o w e d by a gradual i n c r e a s e over s e v e r a l a d d i t i o n a l growth increments, then a f i n a l l e v e l l i n g o f f outwards. A t o t a l o f 37 p r o f i l e s from 14 t r e e s were i n v e s t i g a t e d in t h i s s e c t i o n . Segmented l i n e a r r e g r e s s i o n models, s t a r t i n g a t the lowest r e l a t i v e d e n s i t y v a l u e , were f i t t e d t o t h e s e p r o f i l e s in order t o determine the j u v e n i l e - mature wood t r a n s i t i o n zone (Appendices 5a t o 18a). The p o i n t o f i n t e r s e c t i o n between the two l i n e a r segments co r r e s p o n d i n g t o the segmented model was i d e n t i f i e d as the number o f growth increments from the p i t h (age) a t which the t r a n s i t i o n from j u v e n i l e t o mature wood o c c u r r e d . T a b l e 10 g i v e s a summary o f the t r a n s i t i o n ages o f each t r e e sample s e c t i o n , determined u s i n g segmented l i n e a r r e g r e s s i o n models. To v e r i f y the need o f such models, the "F" r a t i o o f the mean sum o f squares r e s i d u a l value o f a 49 simple l i n e a r r e g r e s s i o n model t o t h a t o f a segmented model, both f i t t e d t o each r e l a t i v e d e n s i t y p r o f i l e , was c a l c u l a t e d f o r each sample s e c t i o n (Table 10). In al1 cases, the c a l c u l a t e d "F" r a t i o s were g r e a t e r than one, i n d i c a t i n g t h a t the segmented r e g r e s s i o n model showed a s m a l l e r sum o f squares r e s i d u a l v a l u e , thus a b e t t e r d a t a f i t . The p r o b a b i l i t y l e v e l a t which the c a l c u l a t e d "F" r a t i o s were s t a t i s t i c a l l y s i g n i f i c a n t v a r i e d from 0.001 t o 0.470. D e s p i t e such a l a r g e range o f l e v e l o f s i g n i f i c a n c e , i t was assumed t h a t the segmented model was the best r e p r e s e n t a t i o n o f the high v a r i a b i l i t y among the values i n some data s e t s , p a r t i c u l a r l y c o n s i d e r i n g t h a t 56 percent o f the "F" r a t i o s were w i t h i n the 0.30 l e v e l o f p r o b a b i 1 i t y . F i g u r e 4a i l l u s t r a t e s the d i s t r i b u t i o n o f sample s e c t i o n h e i g h t s over the number o f growth increments from the p i t h (age) a t which the t r a n s i t i o n o c c u r r e d , when segmented r e g r e s s i o n models were f i t t e d t o the r e l a t i v e d e n s i t y p r o f i l e s . As can be seen, no s y s t e m a t i c v a r i a t i o n t r e n d was found, i n d i c a t i n g t h a t t r a n s i t i o n age and sample height a r e independent. Table 11 g i v e s a summary o f average t r a n s i t i o n ages by sample s e c t i o n h e i g h t s . These averages were 22.36, 22.86, 20.89 and 22.18 years f o r s e c t i o n s sampled a t b r e a s t h e i g h t , 20 p e r c e n t , 40 percent o f t o t a l h e i g h t and f o r a l l s e c t i o n s , r e s p e c t i v e l y . The 50 s i m i l a r i t y o f the average t r a n s i t i o n ages a l s o i n d i c a t e s t h a t t r a n s i t i o n age and hei g h t o f sampling are not r e l a t e d . In a d d i t i o n , the average t r a n s i t i o n age o f 22.18 years f o r a l l s e c t i o n s was very c l o s e t o the maximum re p o r t e d t r a n s i t i o n age f o r D o u g l a s - f i r , which i s 20 years (McKimmy and Campbell, 1982; B a r r e t t and K e l l o g g , 1984; Senft e t . aj.. , 1985; Jozsa and Swan, 1986). 4.2.1 J u v e n i l e - Mature Wood R e l a t i v e D e n s i t y Values Annual j u v e n i l e and mature wood r e l a t i v e d e n s i t y values were determined t o observe w i t h i n t r e e and between t r e e r e l a t i v e d e n s i t y v a r i a t i o n s . Summaries o f r e l a t i v e d e n s i t y values f o r each t r e e a r e presented i n Appendices 20a t o 20o. Table 12 summarizes the r e l a t i v e d e n s i t y p r o f i l e s which i l l u s t r a t e d no c l e a r j u v e n i l e - mature wood t r a n s i t i o n zone. These p r o f i l e s , c o n s i d e r e d as r e p r e s e n t a t i v e o f j u v e n i l e wood, had an average number o f growth increments from the p i t h o f 18.42 and an o v e r a l l mean r e l a t i v e d e n s i t y o f 0.467 ranging from 0.416 t o 0.551. Table 13 summarizes the r e l a t i v e d e n s i t y p r o f i l e s which showed a d e f i n e d j u v e n i l e - mature wood t r a n s i t i o n zone. For these p r o f i l e s , the average numbers o f growth increments co n t a i n e d w i t h i n the j u v e n i l e and mature wood were 22.18 and 19.95, r e s p e c t i v e l y . A l l sample s e c t i o n s 51 mean r e l a t i v e d e n s i t i e s were 0.472, 0.533 and 0.501 f o r j u v e n i l e , mature and t o t a l r e s p e c t i v e l y . Table 14 summarizes r e l a t i v e d e n s i t y values f o r j u v e n i l e and mature wood. T h i s i s a combination o f t h e r e s u l t s shown i n Tables 12 and 13. The o v e r a l l average numbers o f growth increments r e p r e s e n t i n g j u v e n i l e and mature wood were 20.28 and 19.95, r e s p e c t i v e l y . The j u v e n i l e wood t r a n s i t i o n v a l u e i s almost i d e n t i c a l t o the r e p o r t e d maximum t r a n s i t i o n v alue o f 20 growth increments. The o v e r a l l mean j u v e n i l e wood r e l a t i v e d e n s i t y was 0.469, ranging from 0.410 t o 0.561. The lowest j u v e n i l e wood r e l a t i v e d e n s i t y values were found a t s e c t i o n s sampled a t 20 and 40 percent o f t r e e h e i g h t . The o v e r a l l mean mature wood r e l a t i v e d e n s i t y was 0.533 (14 percent g r e a t e r than t h a t f o r j u v e n i l e wood), ranging from 0.474 t o 0.594. 4.3 Base o f the L i v e Crown A t o t a l o f 120 dead branches were sampled from 12 t r e e s i n order t o approximate i n d i v i d u a l h e i g h t t o l i v e crown base curves b e f o r e h a r v e s t , as i l l u s t r a t e d i n Appendix 2. Table 15 shows a summary o f the average number, h e i g h t p o s i t i o n , and number o f growth increments found a t the base o f dead branches i n each t r e e . F i g u r e 4b 52 i l l u s t r a t e s the o v e r a l l d i s t r i b u t i o n o f the branches among t r e e s as a f u n c t i o n o f height p o s i t i o n i n stem and number o f growth increments a t the branch base. As can be seen, the general t r e n d was t h a t the number o f growth increments found i n dead branches i n c r e a s e d with t r e e h e i g h t . It i s Important t o note t h a t as the branches get o l d e r , t h e i r v i g o r decreases, l e a d i n g t o the f o r m a t i o n o f incomplete or absent growth increments a t the branch base (Andrew and G i l l , 1939; Reukema, 1959, 1961). Although few l i v e branches l o c a t e d a t the crown base were examined, the tendency was t o f i n d some d i s c r e p a n c i e s between the number o f growth increments a t the branch base and t h a t o f the t r e e stem a t the p o i n t o f i n t e r s e c t i o n . Growth increment, counts showed f i v e t o e i g h t fewer growth increments i n the lower crown branches than i n the stems a t p o i n t s o f i n t e r s e c t i on. Reukema (1959) s t a t e d two p o s s i b l e reasons f o r t h i s apparent f a i l u r e o f branches i n forming growth increments. The f i r s t was t h a t the c e l l f o r m a t i o n ceased d u r i n g the l a t t e r years o f the branch's l i f e . The second was t h a t a c o n s i d e r a b l e decrease i n cambial a c t i v i t y a t t h i s time produced very narrow growth increments, i . e . one t o two c e l l s wide, without ear 1ywood and latewood d i f f e r e n t i a t i o n . 53 From the above, i t can be concluded t h a t d e s p i t e the f a c t t h a t the lower crown branches appeared h e a l t h y , with p l e n t i f u l f o l i a g e , they are probably no longer p a r t o f the f u n c t i o n a l crown. T h i s may i n t r o d u c e some p o s s i b i l i t y of e r r o r when the base o f the l i v e crown i s r e c o n s t r u c t e d based upon the number o f growth increments found a t the base o f dead branches. In a d d i t i o n , t h i s r e p r e s e n t s an argument in f a v o r o f pruning lower crown l i v e branches. Table 3 summarizes the crown c h a r a c t e r i s t i c s measured f o r the sampled t r e e s a t time o f h a r v e s t . As i l l u s t r a t e d , the o v e r a l l crown base h e i g h t , estimated as the h e i g h t from the ground t o the lowest whorl a t which t h r e e or more l i v e branches were l o c a t e d , was 19.7 m, ranging from 9.0 t o 24.8 m. The overal1 average crown h e i g h t , estimated as a f u n c t i o n o f the average crown r a d i u s (Appendix 1) was 24.2 m, r a n g i n g from 12.0 t o 35.0 m. In some cases, t h i s p o s i t i o n was a l s o I d e n t i f i e d as the crown c o n t a c t or p o i n t o f i n t e r s e c t i o n with neighbouring t r e e s . T h i s was done by l o o k i n g a t symptoms o f whipping or b r e a k i n g damage on the t e r m i n a l shoots o f the branches. F i g u r e s 5a and 5b i l l u s t r a t e the observed data d i s t r i b u t i o n and height p r e d i c t i o n l i n e a r r e g r e s s i o n models f o r crown base h e i g h t and average crown h e i g h t as f u n c t i o n s 54 o f t o t a l t r e e h e i g h t . F i g u r e 6 shows the former l i n e a r r e g r e s s i o n models with the a d d i t i o n o f the observed t o t a l t r e e h e i g h t s f o r each t r e e . As can be seen, both crown base h e i g h t and average crown height i n c r e a s e with i n c r e a s i n g t o t a l t r e e height a t a very constant r a t e o f change. T h i s i n d i c a t e s a f a i r l y c o n s i s t e n t w i t h i n and between crown measurement v a r i a t i o n as a f u n c t i o n o f t o t a l h e i g h t . 4 . 4 R e l a t i o n s h i p s Between J u v e n i l e - Mature Wood T r a n s i t i o n and Base o f the L i v e Crown A s e r i e s o f g r a p h i c a l r e p r e s e n t a t i o n s were prepared i n order t o c l a r i f y the p r o j e c t h y p o t h e s i s . F i g u r e 7 shows two h y p o t h e t i c a l curves r e p r e s e n t i n g t o t a l t r e e h e i g h t and hei g h t t o crown base over the number o f growth increments from the p i t h a t b r e a s t h e i g h t . I f the p r o j e c t hypothesis i s c o r r e c t , the curve r e p r e s e n t i n g height t o crown base w i l l a l s o r e p r e s e n t the p o i n t s o f j u v e n i l e - mature wood t r a n s i t i o n o c c u r r i n g a t d i f f e r e n t h e i g h t s and ages i n t h e t r e e . A l t e r n a t i v e l y , i f the hy p o t h e s i s i s not c o r r e c t , the hei g h t t o crown base w i l l not be c o i n c i d e n t with the p o i n t s a t which the j u v e n i l e - mature wood t r a n s i t i o n o c c u r s . F i g u r e 8 i l l u s t r a t e s t h e h e i g h t t o crown base b e f o r e h a r v e s t , the observed base o f the l i v e crown and c a l c u l a t e d 55 average crown h e i g h t , i . e . d i s t a n c e from the ground t o the widest p a r t o f the crown, a t h a r v e s t . The next step i s t o r e l a t e the former crown h e i g h t p o s i t i o n s t o the corres p o n d i n g j u v e n i l e - mature wood t r a n s i t i o n p o i n t s . These r e l a t i o n s h i p s can, then, be e s t a b l i s h e d b e f o r e or a f t e r h a r v e s t i n order t o t e s t t h e p r o j e c t h y p o t h e s i s as f o l l o w s . 4.4.1 Hypothesis T e s t i n g Before Harvest Appendices 5b t o 19b i l l u s t r a t e i n d i v i d u a l and o v e r a l l ( F i g u r e s 9a, 10a and 10b) r e l a t i o n s h i p s f o r t o t a l h e i g h t , height t o crown base and he i g h t t o j u v e n i l e - mature wood t r a n s i t i o n p o i n t s as f u n c t i o n s o f number o f growth increments from the p i t h a t b r e a s t h e i g h t . In a d d i t i o n , the h e i g h t t o the lowest r e l a t i v e d e n s i t y values i n each sample s e c t i o n was a l s o p l o t t e d t o e s t a b l i s h r e l a t i o n s h i p s with the former curves ( F i g u r e 9b and Appendices 5b t o 19b). The lowest r e l a t i v e d e n s i t y values presented i n F i g u r e 4c and Table 16, were the s t a r t i n g p o i n t s f o r t h e segmented and simple l i n e a r models f i t t e d t o each p r o f i l e . From Appendices 5b t o 19b, the f o l l o w i n g i n d i v i d u a l t r e e c h a r a c t e r i s t i c s are summarized below. 1. The curves r e p r e s e n t i n g h e i g h t over number o f growth increments from the p i t h a t b r e a s t 56 h e i g h t were very s i m i l a r and can be c l a s s i f i e d w i t h i n S i t e C l a s s e s I and II ( i . e . good and medium good) f o r c o a s t a l D o u g l a s - f i r , a c c o r d i n g t o Bruce (1981). The e x c e p t i o n was t r e e CR1 (Appendix 17b) which was sampled from low p r o d u c t i v i t y S i t e C l a s s IV ( i . e . med i um p o o r ) . The lowest r e l a t i v e d e n s i t y curves were, i n g e n e r a l , lower and p a r a l l e l t o the t o t a l h e i g h t curves. The average d i f f e r e n c e between the number o f growth increments between these curves was 7.1, with a range o f two t o 15 and a s t a n d a r d d e v i a t i o n o f 2.9 (Table 16). T h i s suggests not o n l y a very c o n s i s t e n t p a t t e r n o f d e c r e a s i n g r e l a t i v e d e n s i t y in the f i r s t growth increments from the p i t h , but a l s o a tendency t o f i n d the lowest r e l a t i v e d e n s i t y value w i t h i n a c o n s t a n t s h o r t d i s t a n c e from the t r e e apex a t any h e i g h t o f sampling. T h i s d i s t a n c e probably r e p r e s e n t s the upper o n e - t h i r d o f the 1i ve crown. The height t o crown base curves were p a r a l l e l t o the t o t a l h e i g h t curves up t o the r e g i o n between 20 and 40 percent o f the t r e e h e i g h t , 57 and then they d i v e r g e d towards the d i r e c t i o n o f the l i v e crown base a t h a r v e s t . T h i s i s t o be expected, s i n c e the number o f growth increments i n branches i n c r e a s e s with t r e e h eight up t o the base o f the l i v e crown, and then decreases towards the apex. 4 . The height t o crown base curves were a l s o p a r a l l e l and sometimes c o i n c i d e n t with the lowest r e l a t i v e d e n s i t y curves, p a r t i c u l a r l y a t lower sample h e i g h t s . T h e r e f o r e , i t would appear t h a t t h e r e i s a b i o l o g i c a l c o n n e c t i o n between the number o f growth increments found a t the base o f dead branches and t h a t a t which the annual increment r e l a t i v e d e n s i t y value i s lowest. T h i s would suggest t h a t the p r o d u c t i v i t y o f a branch decreases with age, due t o the d e c l i n i n g p h o t o s y n t h e t i c e f f i c i e n c y and r e t e n t i o n o f needles. Growth increment r e l a t i v e d e n s i t y decreases p r o p o r t i o n a l l y u n t i l r e a c h i n g a minimum value when the branch stops producing growth i ncrements. 5. The data p o i n t s r e p r e s e n t i n g h e i g h t p o s i t i o n and number o f growth increments from the p i t h a t which the j u v e n i l e - mature wood 58 • t r a n s i t i o n o c c u r s were lower and g e n e r a l l y p a r a l l e l t o the former t h r e e curves ( i . e . t o t a l h e i g h t , lowest r e l a t i v e d e n s i t y , and crown base) f o r equal numbers o f growth increments from the p i t h . The h e i g h t d i f f e r e n c e between the h e i g h t t o crown base and the t r a n s i t i o n p o i n t s s l i g h t l y decreased with i n c r e a s i n g sample h e i g h t . T h i s suggests t h a t j u v e n i l e - mature wood t r a n s i t i o n o ccurs below the t o t a l h e i g h t curve, the lowest r e l a t i v e d e n s i t y curve and the crown base curve, with a moderate tendency t o approach the crown base curve a t higher sample hei ghts. To i l l u s t r a t e general h e i g h t v a r i a t i o n t r e n d s , data from twelve t r e e s were u t i l i z e d t o estimate the f o l l o w i n g o v e r a l l h e i g h t p r e d i c t i o n models: y = 1 . 0 9 0 9 x ° - 9 6 3 3 0.9968 X y = tota1 he i ght x = growth increments from p i t h r = 0.9781 ( c o r r e l a t i o n c o e f f i c i e n t ; 60 o b s e r v a t i o n s ) y = -3.5855 + 0.8954x - 0.0037x 2 y = lowest r e l a t i v e d e n s i t y height x = growth increments from p i t h r = 0.9324 ( c o r r e l a t i o n c o e f f i c i e n t ; 60 o b s e r v a t i o n s ) 59 y = -6.3482 + 1.0073x - 0.0088x y = crown base h e i g h t x = growth increments from p i t h r = 0.9089 ( c o r r e l a t i o n c o e f f i c i e n t ; 120 o b s e r v a t i o n s ) y = -6.9988 + 0.4853x y = j u v e n i l e - mature wood t r a n s i t i o n h e i g h t x = growth increments from p i t h r = 0.7174 ( c o r r e l a t i o n c o e f f i c i e n t ; 37 o b s e r v a t i o n s ) Trees CR1, CR2 and RF1 were not i n c l u d e d i n these models because they lacked e i t h e r dead branch measurements or j u v e n i l e - mature wood t r a n s i t i o n d e t e r m i n a t i o n . F i g u r e s 9a, 9b, 10a and 10b i l l u s t r a t e t he observed data p o i n t s and corres p o n d i n g h e i g h t p r e d i c t i o n models f o r t o t a l h e i g h t , lowest r e l a t i v e d e n s i t y h e i g h t , crown base h e i g h t and j u v e n i l e - mature wood t r a n s i t i o n h e i g h t as a f u n c t i o n o f number o f growth increments from the p i t h a t b r e a s t h e i g h t . F i g u r e 11 combines the former f o u r h e i g h t p r e d i c t i o n models wi t h the a d d i t i o n o f diagrammatic r e p r e s e n t a t i o n s o f t r e e s a t d i f f e r e n t s t a t e s o f development, t o f a c i l i t a t e the i n t e r p r e t a t i o n o f the r e s u l t s . It can be seen t h a t the o v e r a l l models f o l l o w the same v a r i a t i o n p a t t e r n s as those a l r e a d y d e s c r i b e d f o r i n d i v i d u a l o b s e r v a t i o n s on each t r e e . The lowest r e l a t i v e d e n s i t y curve was p a r a l l e l and very c l o s e t o the t o t a l h e i g h t curve. T h i s suggests t h a t a minimum growth increment r e l a t i v e d e n s i t y value i s l i k e l y 60 t o be found w i t h i n a s h o r t d i s t a n c e from the t r e e apex. The crown base curve was p a r a l l e l t o t h e t o t a l h e i g h t curve up t o about 40 percent o f the t o t a l h e i g h t where i t s t a r t e d t o d i v e r g e towards the p o s i t i o n o f the l i v e crown base a t ha r v e s t . T h i s curve was a l s o p a r a l l e l and very c l o s e l y r e l a t e d t o the lowest r e l a t i v e d e n s i t y curve, p a r t i c u l a r l y a t lower sample h e i g h t s . The simple l i n e a r r e g r e s s i o n model f i t t e d t o the p o i n t s r e p r e s e n t i n g j u v e n i l e - mature wood t r a n s i t i o n was lower and p a r a l l e l t o the curves a l r e a d y d e s c r i b e d . However, due t o the d i s t r i b u t i o n o f the data, t h i s r e g r e s s i o n l i n e does not a c c u r a t e l y r e p r e s e n t the mean values o f the s e c t i o n s sampled a t b r e a s t h e i g h t and 40 percent o f t o t a l h e i g h t , as shown i n F i g u r e 10b. From the r e l a t i v e d e n s i t y p o i n t o f view. F i g u r e 11 can a l s o be i n t e r p r e t e d as a v e r t i c a l r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n . In t h i s p a t t e r n , a maximum growth increment r e l a t i v e d e n s i t y value i s found near the t r e e apex, a minimum value found w i t h i n the upper o n e - t h i r d o f the crown and a gradual i n c r e a s e i n value found toward, and pa s t , t h e crown base u n t i l t h e j u v e n i l e - mature wood t r a n s i t i o n zone, c l o s e t o the base o f the t r e e . The j u v e n i l e and mature growth increment mean r e l a t i v e d e n s i t y values r e p o r t e d i n Table 14 support the i n t e r p r e t a t i o n o f such a c h a r a c t e r i s t i c v e r t i c a l r e l a t i v e d e n s i t y v a r i a t i o n 61 p a t t e r n . S i m i l a r v a r i a t i o n p a t t e r n s were found by Chalk (1953) and by H a r r i s and Orman (1958). The h e i g h t d i f f e r e n c e between he i g h t t o crown base and height t o t r a n s i t i o n p o i n t , f o r equal numbers o f growth increments from the p i t h , as a f u n c t i o n o f t r a n s i t i o n h e i g h t , was p l o t t e d i n F i g u r e 12a. A d e f i n i t e downward t r e n d with i n c r e a s i n g t r a n s i t i o n h e i g h t can be seen. F i g u r e 12b i l l u s t r a t e s the h e i g h t d i f f e r e n c e between t o t a l t r e e h e i g h t and height t o t r a n s i t i o n p o i n t as a f u n c t i o n o f t r a n s i t i o n h e i g h t . In t h i s case, a s l i g h t downward t r e n d with i n c r e a s i n g t r a n s i t i o n h e i g h t was a l s o found, a l t h o u g h the c o r r e l a t i o n c o e f f i c i e n t was not s i g n i f i c a n t a t the 0.05 l e v e l o f p r o b a b i l i t y , i . e . r = -0.2531 (37 o b s e r v a t i o n s ) . T a b l e 17 shows the average h e i g h t d i f f e r e n c e s between hei g h t o f J u v e n i l e - mature wood t r a n s i t i o n p o i n t s , h e i g h t t o crown base and t o t a l h e i g h t . The average d i f f e r e n c e s between h e i g h t o f t r a n s i t i o n p o i n t s and h e i g h t t o crown base were 10.25, 8.71 and 3.85 m f o r s e c t i o n s sampled a t b r e a s t h e i g h t , 20 and 40 p e r c e n t o f t o t a l h e i g h t , r e s p e c t i v e l y . The average d i f f e r e n c e s between height t o t r a n s i t i o n p o i n t s and t o t a l h e i g h t were 18.95, 18.51 and 14.59 m f o r s e c t i o n s sampled a t b r e a s t h e i g h t , 20 and 40 percent r e s p e c t i v e l y . These average h e i g h t d i f f e r e n c e s c o n f i r m the v a r i a t i o n t r e n d s shown in F i g u r e s 12a and 12b. When c o n s i d e r i n g a l l sampled s e c t i o n s , the average j u v e n i l e 62 - mature wood t r a n s i t i o n h e i g h t was found a t 7.95 and 17.72 metres below the crown base and the t r e e apex (Table 17). From the above, s i n c e the t r a n s i t i o n d i d not occur a t the base o f the crown, i t i s concluded t h a t the h y p o t h e s i s , when an a l y z e d b e f o r e h a r v e s t , has not been proven. As d i s c u s s e d e a r l i e r , i t i s important t o p o i n t out t h a t d i s c r e p a n c i e s between the number o f growth increments a t the branch base and t h a t o f the t r e e stem a t the p o i n t o f i n t e r s e c t i o n are l i k e l y t o o c c u r . T h e r e f o r e , the h e i g h t t o crown base p o s i t i o n a t e a r l i e r ages, estimated by c o u n t i n g the number o f growth increments a t the base o f t h e dead branches, can be o v e r e s t i m a t e d . For i n s t a n c e , fewer growth increments i n the lower crown branches than i n t h e stem a t p o i n t s o f i n t e r s e c t i o n would d e f i n e a higher p o s i t i o n o f the crown base, t h u s , a g r e a t e r h e i g h t d i f f e r e n c e between the t r a n s i t i o n p o i n t and the crown base. From the above, i t i s concluded t h a t the d i f f e r e n c e s between h e i g h t o f t r a n s i t i o n p o i n t s and h e i g h t o f crown base c o u l d be reduced t o a p o i n t a t which the h y p o t h e s i s c o u l d be proven, i . e . J u v e n i l e - mature wood t r a n s i t i o n o c c u r s a t the base o f the l i v e crown. However, the e x t e n t o f t h i s r e d u c t i o n was not i n t e n s i v e l y i n v e s t i g a t e d i n the p r o j e c t . 63 4.4.2 Hypothesis T e s t i n g A f t e r Harvest The r e s u l t s o f t e s t i n g the p r o j e c t hypothesis a f t e r h a r v e s t a r e d i f f i c u l t t o v a l i d a t e because a time gap w i l l be r e q u i r e d i n order t o c o n f i r m whether the t r a n s i t i o n between j u v e n i l e and mature wood occurs a t the a c t u a l base o f the l i v e crown. However, a p o s s i b l e a l t e r n a t i v e i s t o estimate the occurrence o f j u v e n i l e - mature wood t r a n s i t i o n h e i g h t s as f u n c t i o n s o f e a r l i e r ages and h e i g h t s a t which the t r a n s i t i o n took p l a c e , i . e . b e f o r e h a r v e s t . These h e i g h t e s t i m a t e s , then, a r e based upon the c a l c u l a t i o n o f an average o f t r a n s i t i o n ages, c a l l e d average t r a n s i t i o n h e i g h t A, and an average o f t r a n s i t i o n h e i g h t s from the t r e e apex, c a l l e d average t r a n s i t i o n h e ight B, as shown i n F i g u r e 13. F i g u r e 14 i l l u s t r a t e s t he number o f growth increments c o r r e s p o n d i n g t o the j u v e n i l e - mature wood t r a n s i t i o n , i . e . determined u s i n g segmented r e g r e s s i o n models, from s e c t i o n s sampled a t b r e a s t h e i g h t , 20 and 40 percent, and o v e r a l l s e c t i o n averages (average o f t r a n s i t i o n ages) f o r each t r e e . F i g u r e 15 i l l u s t r a t e s the d i f f e r e n c e s between t o t a l h e i g h t s and e a r l i e r j u v e n i l e - mature wood t r a n s i t i o n h e i g h t s from s e c t i o n s sampled a t b r e a s t h e i g h t , 20 and 40 per c e n t , and o v e r a l l s e c t i o n averages (average t r a n s i t i o n height B) f o r each t r e e . 64 For each t r e e , the average t r a n s i t i o n age was converted t o average t r a n s i t i o n h eight A by i n t e r p o l a t i o n from the curve r e p r e s e n t i n g h e i g h t over number o f growth increments from the p i t h a t b r e a s t h e i g h t (Appendices 5b t o 18b). Both average t r a n s i t i o n h e i g h t s A and B were c a l c u l a t e d because no s y s t e m a t i c data v a r i a t i o n t r e n d w i t h i n and between t r e e s was d e t e c t e d , as shown in F i g u r e s 14 and 15. Observed data d i s t r i b u t i o n and h e i g h t p r e d i c t i o n models f o r average t r a n s i t i o n h e i g h t s A and B, crown base height and average h e i g h t as f u n c t i o n s o f t o t a l t r e e h e i g h t are shown i n F i g u r e s 16a, 16b, 5a and 5b r e s p e c t i v e l y . F i g u r e 17 shows a combination o f the former f o u r l i n e a r r e g r e s s i o n models with the a d d i t i o n o f the c o r r e s p o n d i n g t o t a l t r e e h e i g h t o f each t r e e . I t can be seen t h a t the h e i g h t p o s i t i o n s p e r t a i n i n g t o average crown, average t r a n s i t i o n A, l i v e crown base and average t r a n s i t i o n B i n c r e a s e d with i n c r e a s i n g t o t a l t r e e h e i g h t . The s l o p e s o f these models i n d i c a t e d r e l a t i v e l y constant r a t e s o f h e i g h t change. The average crown h e i g h t r e g r e s s i o n l i n e was l o c a t e d higher than those c o r r e s p o n d i n g t o the average t r a n s i t i o n h e i g h t A, l i v e crown base height and average t r a n s i t i o n h e i g h t B. The average t r a n s i t i o n h e i g h t A r e g r e s s i o n l i n e was higher than t h a t c o r r e s p o n d i n g t o average t r a n s i t i o n h e i g h t B and t o l i v e crown base 65 h e i g h t . Only one t r e e a t the lower h e i g h t end showed a l i v e crown base higher than the average t r a n s i t i o n height. A, r e v e r s i n g the v a r i a t i o n p a t t e r n e s t a b l i s h e d a t the higher h e i g h t end. The same r e l a t i o n s h i p s can be seen i n the summary o f average h e i g h t d i f f e r e n c e s presented i n Table 18. The average d i f f e r e n c e between t o t a l h e i g h t and average crown h e i g h t , average t r a n s i t i o n h e i g h t A, crown base h e i g h t and average t r a n s i t i o n h e i g h t B were 10.26, 12.63, 14.76 and 17.91 m, r e s p e c t i v e l y . S i n c e e a r l i e r r e s u l t s showed t h a t the o v e r a l l average o f j u v e n i l e - mature t r a n s i t i o n h e i g h t was found 17.72 m below the t r e e apex (Table 17), i t can be s t a t e d t h a t average t r a n s i t i o n h e i g h t B, l o c a t e d 17.91 below the t r e e apex, would b e t t e r r e p r e s e n t the p o s s i b l e o c c urrence o f t r a n s i t i o n from the t r e e apex a t h a r v e s t . The average height d i f f e r e n c e between t r a n s i t i o n h e ight A and average crown h e i g h t was 2.16 m and between t r a n s i t i o n h e i g h t A and l i v e crown base h e i g h t i t was -2.21 m (Table 18). The c o r r e l a t i o n c o e f f i c i e n t s o b t a i n e d between t r a n s i t i o n h e i g h t A, average crown height and l i v e crown base he i g h t were 0.7936 and 0.8419, r e s p e c t i v e l y (Table 19). The average h e i g h t d i f f e r e n c e between average t r a n s i t i o n h e i g h t B and average crown he i g h t was -3.12 m, and between average t r a n s i t i o n h e i g h t B and l i v e crown base height i t was -7.50 m (Table 18). The c o r r e l a t i o n 66 c o e f f i c i e n t s between average t r a n s i t i o n h e i g h t B» average crown h e i g h t and l i v e crown base h e i g h t were 0.5888 and 0.7340, r e s p e c t i v e l y (Table 19). From the above, i t can be summarized t h a t average t r a n s i t i o n h e i g h t A o c c u r r e d below the average crown h e i g h t and above the l i v e crown base h e i g h t . Average t r a n s i t i o n height B o c c u r r e d below both the average crown he i g h t and the l i v e crown base h e i g h t . N e i t h e r o f the c a l c u l a t e d j u v e n i l e - mature wood average t r a n s i t i o n h e i g h t s A nor B o c c u r r e d a t the base o f the l i v e crown p o s i t i o n a f t e r h a r v e s t . Average t r a n s i t i o n h e i g h t A seemed t o be c l o s e r t o the average crown he i g h t and the l i v e crown base h e i g h t than the average t r a n s i t i o n h e i g h t B. However, assuming t h a t the t r a n s i t i o n would be l i k e l y t o occur below the base o f the l i v e crown p o s i t i o n , as demonstrated e a r l i e r , the average t r a n s i t i o n h e i g h t A might o v e r e s t i m a t e the h e i g h t o f the t r a n s i t i o n . Average t r a n s i t i o n h e i g h t B, then, would b e t t e r r e p r e s e n t t h e p o s s i b l e o c c urrence o f the t r a n s i t i o n a f t e r h a r v e s t . As i l l u s t r a t e d i n Table 17 and F i g u r e 12a, the d i f f e r e n c e between he i g h t t o l i v e crown base and he i g h t t o t r a n s i t i o n p o i n t s b e f o r e h a r v e s t decrease with i n c r e a s i n g t r e e h e i g h t . The average h e i g h t d i f f e r e n c e s were 10.25, 8.71 and 3.85 m f o r s e c t i o n s sampled a t b r e a s t h e i g h t , 20 and 40 percent o f t o t a l t r e e h e i g h t r e s p e c t i v e l y (Table 67 17). Assuming t h a t these h e i g h t d i f f e r e n c e s w i l l c o ntinue t o decrease with t r e e h e i g h t , the average t r a n s i t i o n h e i g h t B found a t 3.12 m (Table 18) below the observed base o f the l i v e crown p o s i t i o n seemed a very reasonable estimate o f the o c c u r r e n c e o f the t r a n s i t i o n a f t e r h a r v e s t . In view o f the above, i t i s concluded t h a t the average j u v e n i l e - mature wood t r a n s i t i o n h e i g h t B, c a l c u l a t e d as a f u n c t i o n o f e a r l i e r t r a n s i t i o n h e i g h t p o s i t i o n s , best r e p r e s e n t s an a c t u a l e s timate o f t r a n s i t i o n o c c u r r e n c e . Since n e i t h e r o f the estimated average t r a n s i t i o n h e i g h t s A nor B o c c u r r e d a t the base o f the l i v e crown p o s i t i o n , i t f o l l o w s t h a t the hypothesis when a n a l y z e d a f t e r h a r v e s t i s not proven. The s i m i l a r r e s u l t s found when t e s t i n g the hypothesis b e f o r e and a f t e r h a r v e s t can be, i n p a r t , supported by Larson (1969) who s t a t e d t h a t : "The major changes i n wood fo r m a t i o n and q u a l i t y occur i n the lower stem beneath the l i v i n g crown or beneath the most a c t i v e branches o f the crown." In t h i s p r o j e c t , the t r a n s i t i o n from j u v e n i l e t o mature wood o c c u r r e d below the a r b i t r a r y d e f i n i t i o n o f l i v e crown base, i . e . h e i g h t t o the lowest whorl which has t h r e e or more l i v e branches. However, Larson's i n t e r p r e t a t i o n s o f the j u v e n i l e - mature wood t r a n s i t i o n , the e x t e n s i o n o f the l i v i n g crown and l o c a t i o n o f the most a c t i v e branches 68 i n the crown, may not be b i o l o g i c a l l y c o i n c i d e n t with the r e s u l t s o f t h i s p r o j e c t . T h i s suggests t h a t a wrong d e f i n i t i o n o f what i s in r e a l i t y the base o f the l i v e crown, as i t r e l a t e s t o wood fo r m a t i o n , may a l s o lead t o a wrong answer when t e s t i n g the p r o j e c t h y p o t h e s i s . 4.5 Pruned Trees As was s t a t e d i n the l i t e r a t u r e review, pruning o f l i v e and vigorous lower branches i n the crown can produce a f a s t e r change from j u v e n i l e t o mature wood, t h e r e f o r e r e d u c i n g the p r o p o r t i o n o f j u v e n i l e wood core i n a g i v e n t r e e . In t h i s p r o j e c t , two pruned t r e e s were analyzed i n order t o i n v e s t i g a t e the e f f e c t s o f p r u n i n g on annual increment r e l a t i v e wood d e n s i t y . The r e s u l t s were then an a l y z e d t o determine t h e i r r e l a t i o n s h i p t o the p r o j e c t hypothes i s. F i g u r e s 18 and 19 show the r e l a t i v e d e n s i t y p r o f i l e s as a f u n c t i o n o f number o f growth increments from the p i t h . As shown, a d d i t i o n a l sample s e c t i o n s a t ten percent o f t o t a l t r e e height were i n c l u d e d because they were l o c a t e d w i t h i n the pruning a r e a . T h i s a r e a comprised the lower o n e - t h i r d o f t h e l i v e crown, r e p r e s e n t i n g a h e i g h t o f approximately f o u r t o f i v e metres, i . e . below the sample s e c t i o n s a t 20 percent o f t o t a l h e i g h t . In these f i g u r e s , 69 the arrows in the r e l a t i v e d e n s i t y p r o f i l e s on the s e c t i o n s sampled a t b r e a s t h e i g h t and 10 percent o f t o t a l h e i g h t i n d i c a t e the year i n which the pruning was done, i . e . 1954 or 30 years b e f o r e the t r e e s were har v e s t e d . The r e l a t i v e d e n s i t y p r o f i l e s o f s e c t i o n s sampled a t b r e a s t h e i g h t and 10 percent o f t o t a l t r e e h e i g h t i n t r e e RF2 showed a gradual i n i t i a l i n c r e a s e or decrease i n the f i r s t growth increments from the p i t h , f o l l o w e d by a sudden i n c r e a s e soon a f t e r the p r u n i n g was done, and a f i n a l gradual decrease outwards. The r e l a t i v e d e n s i t y p r o f i l e s f o r the same sample s e c t i o n s i n t r e e RF3 showed a s i m i l a r v a r i a t i o n p a t t e r n , u n t i l a f t e r pruning was done, and then they d i s t i n c t i v e l y showed a f i n a l l e v e l l i n g o f f outwards. T h i s suggests t h a t r e l a t i v e d e n s i t y can be i n c r e a s e d by pruning o f lower crown 1i ve branches. The d i f f e r e n t r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n s o f these t r e e s a f t e r p runing was probably due t o the f a c t t h a t RF2 was more dominant and open grown than RF3. T h e r e f o r e , RF2 was a b l e t o overcome the e f f e c t s o f pruning i n a r e l a t i v e l y s h o r t time. The numbers o f growth increments from the p i t h , b e f o r e pruning, a t b r e a s t h e i g h t and 10 percent o f t o t a l h e i g h t were 21 and 17 f o r t r e e RF2, and 15 and 13 f o r t r e e RF3. The o v e r a l l average number o f growth increments o f the 70 former s e c t i o n s was 16.5. T h i s average number a l s o r e p r e s e n t s an estimate o f the j u v e n i l e - mature t r a n s i t i o n o c c u r r e n c e , s i n c e i t d e l i m i t s two d i f f e r e n t r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n s from the p i t h . For both t r e e s , the mean r e l a t i v e d e n s i t y f o r j u v e n i l e wood was 0.441, rang i n g from 0.370 t o 0.490. The mean r e l a t i v e d e n s i t y f o r mature wood was 0.494 (nine percent g r e a t e r than t h a t f o r j u v e n i l e wood), ranging from 0.640 t o 0.410 (Appendices 20p and 20q). When the o v e r a l l average number o f growth increments a t which the t r a n s i t i o n o c c u r r e d a f t e r pruning, i . e . 16.5, was compared t o t h a t c o r r e s p o n d i n g t o t r e e s without pruning, i . e . 22.18 (Table 11), the d i f f e r e n c e was about 26 perce n t . From the above, i t i s concluded t h a t pruning o f lower crown l i v e branches can produce both an i n c r e a s e i n annual increment mean r e l a t i v e d e n s i t y and a decrease i n the p r o p o r t i o n o f j u v e n i l e wood i n D o u g l a s - f i r by a c c e l e r a t i n g the o c c u r r e n c e o f j u v e n i l e - mature wood t r a n s i t i o n . S i n c e o n l y two t r e e s were an a l y z e d , these r e s u l t s should be t r e a t e d as e x p l o r a t o r y . However, they are good i n d i c a t o r s o f p o s s i b l e b e n e f i t s i n a d d i t i o n t o o b t a i n i n g more c l e a r wood, when pruning lower crown l i v e branches. Furthermore, assuming t h a t these branches c o n t r i b u t e l i t t l e or nothin g t o stem wood fo r m a t i o n , w hile u t i l i z i n g t r e e r e s o u r c e s , i t 71 might be worthwhile t o c o n s i d e r the pruning o f young-growth Doug 1as-f i r . When r e l a t i n g these r e s u l t s t o the p r o j e c t h y p o t h e s i s , i t would appear t h a t pruning can a c c e l e r a t e the j u v e n i l e - mature wood t r a n s i t i o n , which otherwise would need more time i n which t o happen. Then, i f i n f a c t the t r a n s i t i o n occurs below the base o f the l i v e crown i n unpruned t r e e s , the t r a n s i t i o n c o u l d be s h i f t e d upwards by pruning lower crown l i v e branches. In view o f the above, i t i s concluded t h a t when the p r o j e c t h y p o t h e s i s was t e s t e d on pruned t r e e s , the j u v e n i l e - mature wood t r a n s i t i o n would occur a t the m o d i f i e d base o f the l i v e crown, which r e p r e s e n t s the upper l i m i t o f pruning h e i g h t . T h e r e f o r e , the hypothesis can be proven as c o r r e c t . It i s important t o note t h a t more r e s e a r c h on pruned t r e e s i s needed f o r f u r t h e r development o f these r e s u l t s . 72 5.0 CONCLUSIONS 1) The h o r i z o n t a l annual increment mean r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n a t the f i v e sample h e i g h t s was c h a r a c t e r i z e d by an i n i t i a l decrease t o a p o i n t w i t h i n the f i r s t growth increments from the p i t h , f o l l o w e d by a gradual i n c r e a s e and s t a b i l i z a t i o n outwards, p a r t i c u l a r l y i n the lower sample s e c t i o n s ( i . e . b r e a s t h e i g h t , 20 and 40 percent o f t o t a l t r e e h e i g h t ) . 2) The v e r t i c a l annual increment mean r e l a t i v e d e n s i t y v a r i a t i o n p a t t e r n was c h a r a c t e r i z e d by a decrease with i n c r e a s i n g t r e e h e i g h t . 3) Based on the v a r i a t i o n p a t t e r n o f the data p o i n t s , p e r t a i n i n g t o annual increment r e l a t i v e d e n s i t y and number o f growth increments from the p i t h , no evidence o f j u v e n i l e - mature t r a n s i t i o n zone was found p r i m a r i l y a t s e c t i o n s sampled a t 60 and 80 percent o f t o t a l t r e e h e i g h t . The average number o f growth increments from the- p i t h f o r these s e c t i o n s was 18.42, ran g i n g from 4 t o 33. 4) A g r e a t e r evidence o f j u v e n i l e - mature wood t r a n s i t i o n zone was found a t s e c t i o n s sampled a t b r e a s t h e i g h t , 20 73 and 40 percent o f t o t a l t r e e h e i g h t . The average numbers o f growth increments a t which j u v e n i l e - mature wood t r a n s i t i o n o c c u r r e d , when segmented r e g r e s s i o n models were f i t t e d t o r e l a t i v e d e n s i t y p r o f i l e s , were 22.36, 22.86, 20.89 and 22.18 f o r s e c t i o n s sampled a t b r e a s t h e i g h t , 20 pe r c e n t , 40 percent o f t o t a l h e i g h t and f o r a l l s e c t i o n s , r e s p e c t i v e l y . Segmented r e g r e s s i o n a n a l y s i s , t h e r e f o r e , produced a f a i r l y c o n s i s t e n t demarcation between j u v e n i l e and mature wood, among sample h e i g h t s , d e s p i t e the l a r g e v a r i a b i l i t y among the va l u e s i n some o f the r e l a t i v e dens i t y p r o f i 1 e s . 5) The o v e r a l l annual increment mean mature wood r e l a t i v e d e n s i t y was 14 percent higher than t h a t f o r J u v e n i l e wood. The lowest annual increment mean j u v e n i l e wood r e l a t i v e d e n s i t y was found a t s e c t i o n s sampled a t 20 and 40 percent o f t o t a l t r e e h e i g h t . 6) I n d i v i d u a l and o v e r a l l h e i g h t r e l a t i o n s h i p s , b e f o r e h a r v e s t , f o r t o t a l h e i g h t , height t o crown base, h e i g h t t o the lowest r e l a t i v e d e n s i t y value and height t o j u v e n i l e - mature wood t r a n s i t i o n p o i n t as f u n c t i o n s o f number o f growth increments from the p i t h i n d i c a t e d t h a t t h e : 74 Lowest r e l a t i v e d e n s i t y curve was p a r a l l e l and very c l o s e t o the t o t a l h e i g h t curve, suggesting t h a t a minimum growth Increment r e l a t i v e d e n s i t y value i s l i k e l y t o be found i n the f i r s t growth increments from the p i t h and w i t h i n a s h o r t d i s t a n c e from the t r e e apex; Height t o crown base curve was p a r a l l e l t o the t o t a l h e i g h t curve up t o about 40 percent o f the t o t a l h e i g h t where i t s t a r t e d t o d i v e r g e towards the l i v e crown base p o s i t i o n a t h a r v e s t ; Height t o crown base curve was a l s o p a r a l l e l and sometimes c o i n c i d e n t with the lowest r e l a t i v e d e n s i t y curve, i n d i c a t i n g a p o s s i b l e b i o l o g i c a l c o n n e c t i o n between the number o f growth increments a t the base o f dead branches and t h a t a t which the annual increment r e l a t i v e d e n s i t y value i s lowest; and Simple l i n e a r model f i t t e d t o the p o i n t s i n d i c a t i n g j u v e n i l e - mature wood t r a n s i t i o n was lower and p a r a l l e l t o the curves d e s c r i b e d p r e v i o u s l y . 75 Observed data d i s t r i b u t i o n and height p r e d i c t i o n models, a f t e r h a r v e s t , f o r t o t a l h e i g h t , average crown h e i g h t , l i v e crown base h e i g h t , average t r a n s i t i o n h e i g h t A (estimated as a f u n c t i o n o f e a r l i e r t r a n s i t i o n ages) and average t r a n s i t i o n h eight B (estimated as a f u n c t i o n o f e a r l i e r t r a n s i t i o n h e i g h t s ) i n d i c a t e d t h a t : a. The average crown h e i g h t p o s i t i o n s were higher than the p o s i t i o n s c o r r e s p o n d i n g t o average t r a n s i t i o n A, l i v e crown base and average t r a n s i t i o n B; b. The average t r a n s i t i o n A h e i g h t p o s i t i o n s were l o c a t e d between those p o s i t i o n s c o r r e s p o n d i n g t o the average crown and base o f the l i v e crown; c. The average t r a n s i t i o n B h e i g h t p o s i t i o n s were l o c a t e d below those p o s i t i o n s c o r r e s p o n d i n g t o the average crown and the base o f the l i v e crown; and d. Assuming t h a t the t r a n s i t i o n would be l i k e l y t o occur below the l i v e crown base p o s i t i o n , the average t r a n s i t i o n h e i g h t A might o v e r e s t i m a t e the h e i g h t o f the t r a n s i t i o n , then, the average t r a n s i t i o n h e i g h t B would b e t t e r r e p r e s e n t the p o s s i b l e o c currence o f the t r a n s i t i o n a f t e r h a r v e s t . 76 8) Pruning o f lower crown l i v e branches produced both an in c r e a s e i n the annual increment r e l a t i v e d e n s i t y and a decrease i n the p r o p o r t i o n o f j u v e n i l e wood by a c c e l e r a t i n g the j u v e n i l e - mature wood t r a n s i t i o n . The average number o f growth increments a t which the t r a n s i t i o n o c c u r r e d a f t e r pruning was 16.5. 9) When t e s t i n g the p r o j e c t h y p o t h e s i s on unpruned t r e e s , b e f o r e and a f t e r h a r v e s t , the t r a n s i t i o n i n r e l a t i v e d e n s i t y from j u v e n i l e t o mature wood d i d not occur a t the base o f the l i v e crown, as d e f i n e d . In both cases, t h e t r a n s i t i o n o c c u r r e d below the base o f the l i v e crown. T h e r e f o r e , the hyp o t h e s i s has not been proven. 10) When the hyp o t h e s i s was t e s t e d on pruned t r e e s , the j u v e n i l e - mature wood t r a n s i t i o n d i d occur a t the base o f the l i v e crown, which r e p r e s e n t e d the upper l i m i t o f pruning h e i g h t . The hypothesis i n t h i s case has, t h e r e f o r e , been proven. 11) R e s u l t s o f hypothesis t e s t i n g seemed t o depend upon the d e f i n i t i o n given t o the base o f the l i v e crown. F u r t h e r r e s e a r c h needs t o be done, not o n l y t o f i n d a more p r e c i s e d e f i n i t i o n o f what should b i o l o g i c a l l y be co n s i d e r e d the base o f the l i v e crown, but a l s o t o i n v e s t i g a t e the i m p l i c a t i o n o f such d e f i n i t i o n on wood format ion. 77 LITERATURE CITED A l d r i d g e , F. and R.H. Hudson. 1959. Growing q u a l i t y o f softwoods. Quart. J . F o r e s t r y 53:210-219. A l l e n , G.S. and J.N. Owens. 1972. The L i f e H i s t o r y o f D o u g l a s - f i r . C.F.S. Cat. No. F042-4972. 139 pp. Anderson, E.A. 1951. T r a c h e i d length v a r i a t i o n i n c o n i f e r s as r e l a t e d t o d i s t a n c e from p i t h . J . F o r e s t r y 49(l):38-42. Andrew, S.R. and L.S. G i l l . 1939. Determining the time branches on l i v i n g t r e e s have been dead. J . F o r e s t r y 37:930-935. Bar e f o o t , A . C , H i t c h i n g s , R.G. , E l wood, E.L. and E. Wilson. 1970. The r e l a t i o n s h i p between l o b l o l l y p i n e f i b e r morphology and k r a f t paper p r o p e r t i e s . Tech. B u l l . No. 202. N.C A g r i c . Exp. S t . , N.C.S.U., R a l e i g h . 89 pp. B a r r e t t , J.D. and R.M. K e l l o g g . 1984. S t r e n g t h and s t i f f n e s s o f second-growth D o u g l a s - f i r dimension lumber. F o r i n t e k Canada Corp., Vancouver, B.C. Tech. Rep. 57 pp. . 1986. Lumber q u a l i t y from second-growth managed f o r e s t s . Proc. A T e c h n i c a l Workshop: What Does i t Mean t o F o r e s t Management and F o r e s t Products? F.P.R.S., S.A.F., Bellingham, Wa. pp. 57-71. Bendtsen, B.A. 1978. P r o p e r t i e s o f wood from improved and i n t e n s i v e l y managed t r e e s . F o r e s t Prod. J . 28(10):61-72. and J . S e n f t . 1986. Mechanical and anatomical p r o p e r t i e s i n i n d i v i d u a l growth r i n g s o f plantation-grown e a s t e r n Cottonwood and l o b l o l l y p i n e . Wood and F i b e r S c i . 18(l):23-38, Boone, R.S. and M. Chudnoff. 1972. Compression wood for m a t i o n and o t h e r c h a r a c t e r i s t i c s o f plantation-grown Pi nus c a r i b a e a . U.S.D.A. For. Serv. Res. Pap. I.T.F.-13. Int. Trop. For., Puerto Rico. 15 pp. 78 B o u t e l j e , J.B. 1968. J u v e n i l e wood, with p a r t i c u l a r r e f e r e n c e t o northern spruce. Svensk Papptidn. 71(17):581-585. Bower, R.W., De Souza, A. and J.F. S e n f t . 1976. P h y s i c a l and mechnical p r o p e r t i e s o f fast-grown, p l a n t a t i o n Caribbean pine (Pi nus. car ibaea) from B r a z i l , South America. Purdue Univ. Res. B u l l . No 936. L a f a y e t t e , Ind. 6pp. B r i g g s , D.G. and W.R. Smith. 1986. E f f e c t s o f s i l v i c u l t u r a l p r a c t i c e s on wood p r o p e r t i e s o f c o n i f e r s - a review. Proc. o f D o u g l a s - f i r Stand Management f o r the Future. Univ. Wa., S e a t t l e , pp. 108-117. B r i t i s h Columbia M i n i s t r y o f F o r e s t s . 1980. F o r e s t and Range Resource A n a l y s i s . T e c h n i c a l Report. ISBN 0-7719-8324-7. V o l . I I . pp. 577-602; 693-712. B r i t t , K.W. 1970. J_n Handbook o f Pulp and Paper Techno1ogy. Zobe1, B.J. ed. Pu1pwood mensuration. Van Nostrand Reinhold Co. N.Y. pp.125-132. Brown, C L . 1970. P h y s i o l o g y o f wood fo r m a t i o n i n c o n i f e r s . Wood S c i . 3 ( l ) : 8 - 2 2 . Bruce, D.I. 1981. C o n s i s t e n t height-growth and growth r a t e estimates f o r remeasured p l o t s . F o r e s t S c i . 27(7):711-725. Brunden, M.N. 1964. S p e c i f i c g r a v i t y and f i b e r length i n crown-formed wood. F o r e s t Prod. J . 14(1):13-17. Bryant, P.A.V. 1984. The impact o f f a s t growth in p l a n t a t i o n s on wood q u a l i t y and u t i l i z a t i o n . Proc. Symp. on S i t e and P r o d u c t i v i t y o f F a s t Growing P l a n t a t i o n s . I.U.F.R.O., P r e t o r i a , S. A f r i c a . pp. 403-410. Chang, C.I. and R.W. Kennedy. 1967. I n f l u e n c e o f s p e c i f i c g r a v i t y and growth r a t e on dry wood p r o d u c t i o n i n p l a n t a t i o n grown white spruce. F o r e s t r y Chron. 43(2):165-173. Chalk, L. 1953. V a r i a t i o n o f d e n s i t y i n stems o f D o u g l a s - f i r . F o r e s t r y 26:33-36. 79 C l a r k , J . 1961. P h o t o s y n t h e s i s and r e s p i r a t i o n i n white spruce and balsam f i r . N.Y. S t a t e C o l l . For., Syracuse Univ. B u l l . 85. 72 pp. Cooper, G.A. 1960. S p e c i f i c g r a v i t y o f red p i n e as r e l a t e d t o stem and crown-formed wood. Iowa S t a t e J . S c i . 34(4) -.693-708. Cown, D.J. 1973. E f f e c t o f severe t h i n n i n g and pruning treatments on the i n t r i n s i c wood p r o p e r t i e s o f young r a d i a t a p i n e . N.Z. J . For. S c i . 3(3):379-389. . 1975. V a r i a t i o n s i n t r a c h e i d dimensions i n the stem o f a 26-year-old r a d i a t a p i n e . A p p i t a 28(4):237-245. . 1976. D e n s i t o m e t r i c s t u d i e s on young D o u g l a s - f i r . Unpub. Ph. D. T h e s i s . Dept. o f F o r e s t r y , Univ. B.C. 241 pp. C r i s t , J.B., Dawson, D.H. and J.A. Nelson. 1977. Wood and bark q u a l i t y o f j u v e n i l e jack p i n e and e a s t e r n l a r c h grown under i n t e s ? v e c u l t u r e . Tappi Wood Chem. Conf. For. B i o l . Madison, Wi. pp. 221-216. Draper, N.R. and H. Smith. 1981. A p p l i e d Regression A n a l y s i s . Second E d i t i o n . John Wiley and Sons., N.Y. pp. 250-254. Dadswell, H.E. 1958. Wood s t r u c t u r e v a r i a t i o n s o c c u r r i n g d u r i n g t r e e growth and t h e i r i n f l u e n c e on p r o p e r t i e s . J . I n s t . Wood. S c i . (1):11-33. De Guth, E.B. 1980. R e l a t i o n s h i p between wood d e n s i t y and t r e e diameter in Pi nus e 1 1 i o t t i i o f Misiones, A r g e n t i n a . Proc. Div. 5. I.U.F.R.O. Meet., Oxford, England. Dinwoodie, J.M. 1961. T r a c h e i d and f i b e r length i n timber. A review o f l i t e r a t u r e . F o r e s t r y 34(2):125-144. Duff, G.H. and N.J. Nolan. 1953. Growth and morphogenesis i n the Canadian f o r e s t s p e c i e s . I. The c o n t r o l s o f cambial and a p i c a l a c t i v i t y i n Pi nus res i nosa A i t . Can. J . Bot. (31):471-513. 80 E l l i o t t , G.K. 1958. S p i r a l g r a i n i n second-growth D o u g l a s - f i r and hemlock. F o r e s t Prod. J . 8:205-211. E l l i o t t , G.K. 1970. Wood d e n s i t y i n c o n i f e r s . Commonwealth F o r e s t r y Bureau. Oxford, England, T e c h n i c a l Communication No. 8. 44 pp. E r i c k s o n , H.D. and T. Arima. 1974. D o u g l a s - f i r wood q u a l i t y s t u d i e s . P a r t I I . E f f e c t s o f age and s t i m u l a t e d growth on f i b r i l a ngle and chemical c o n s t i t u e n t s . Wood S c i . Tech. 8(4):255-265. and A.T. H a r r i s o n . 1974. D o u g l a s - f i r wood q u a l i t y s t u d i e s . P a r t I. E f f e c t s o f age and s t i m u l a t e d growth on wood d e n s i t y and anatomy. Wood S c i . Tech. 8(4):207-226. F i e l d i n g , J.M. 1967. The i n f l u e n c e o f s i 1 v i c u 1 t u r a 1 p r a c t i c e s on wood p r o p e r t i e s . Int. Rev. F o r e s t r y Res., N.Y. 2:99-126. F o e l k e l , C.F.B., B a r r i c h e l o , L.E.G., G a r c i a , W. and J.O. B r i t o . 1976. K r a f t c e l l u l o s e o f j u v e n i l e and adu11 wood o f Pi nus e11ott i i . I.P.E.F., P i r a c i c a b a (12):127-142. Forward, D.F. and N.J. Nolan. 1964. Growth and morphogenesis i n the Canadian f o r e s t s p e c i e s . V I I . Progress and c o n t r o l o f l o n g i t u d i n a l growth o f branches i n Pi nus res i nosa A i t . Can. J . Bot. 42:923-950. Fo w e l l s , H.A. 1965. S i I v i e s o f F o r e s t Trees o f the U n i t e d S t a t e s . U.S.D.A. F.S. A g r i c u l t u r e Handbook no. 271. pp. 546-553. F r a s e r , D.A. 1962. A p i c a l and r a d i a l growth o f white spruce (Pi cea g1auca (Moench) Voss) a t Chalk R i v e r , O n t a r i o , Canada. Can. J . Bot. 40:659-668. F r e e l a n d , R.O. 1952. E f f e c t o f age o f leaves upon the r a t e o f p h o t o s y n t h e s i s i n some c o n i f e r s . P l a n t . P h y s i o l . 27(4):685-690. Gerhards, C C . 1979. E f f e c t o f high-temperature d r y i n g on t e n s i l e s t r e n g t h o f D o u g l a s - f i r 2' x 4's. F o r e s t Prod. J . 29(3):39-46. 81 G e r i s c h e r , G.F. and A.M. De V i l l i e r s . 1963. The e f f e c t o f heavy pruning on timber p r o p e r t i e s . For. South A f r i c a . 3:15-41. Goggans, J.F. 1961. The i n t e r p l a y o f environment and h e r e d i t y as f a c t o r s c o n t r o l l i n g wood p r o p e r t i e s in c o n i f e r s with s p e c i a l emphasis on t h e i r e f f e c t s on s p e c i f i c g r a v i t y . Tech. Rept. I I . N.C. S t a t e Univ., Ra1eigh. 56 pp. Gonzalez, J.S. and R.M. K e l l o g g . 1978. E v a l u a t i n g wood s p e c i f i c g r a v i t y i n a t r e e improvement program. W.F.P.L. Info. Rep. VP-X.183. Vancouver, B.C. Canada. 14 pp. Hale, J.D. and K.G. Fenson. 1931. The r a t e o f growth and d e n s i t y o f the wood o f white spruce. Canada Dept. Int. For. Ser. C i r c . No. 30. 18 pp. and J.B. P r i n c e . 1940. D e n s i t y and r a t e o f growth in the spruce and balsam f i r o f e a s t e r n Canada. Canada Dept. Mines and Res. For. Serv. Bul1. 94. 43 pp. H a r r i s , J.M. 1969a. The use o f beta rays i n determining wood p r o p e r t i e s . P a r t 1 - 5. N.Z. J . S c i . 12(2):396-451. . 1969b. On the cause o f s p i r a l g r a i n i n corewood o f r a d i a t a p i n e . N.Z. J . Bot. 7(3):189-213. and H.R. Orman. 1958. The p h y s i c a l and mechanical p r o p e r t i e s o f New Zealand grown D o u g l a s - f i r . N.Z. For. Serv. For. Res. I n s t . Tech. Pap. No. 24. 87 pp. Haygreen, J.G. and J.L. Bowyer. 1982. F o r e s t Products and Wood S c i e n c e . The Iowa S t a t e U n i v e r s i t y P r e s s . 495 pp. Hudson, D.J. 1966. F i t t i n g segmented curves whose j o i n p o i n t s have t o be e stimated. J . Am. S t a t . Assoc. 61(316):1097-1129. Husch, B., M i l l e r , C.I. and T.W. Beers. 1982. F o r e s t Mensuration. John Wiley and Sons, Inc., N.Y. pp. 80-89. 82 I f j u G. 1969. Within-growth-ring v a r i a t i o n i n some p h y s i c a l p r o p e r t i e s o f Southern Pine Wood. Wood S c i . 2(1):11-19. I f j u G. and R.W. Kennedy. 1962. Some v a r i a b l e s a f f e c t i n g m i c r o t e n s i l e s t r e n g t h o f D o u g l a s - f i r . F o r e s t Prod. J . 12:213-217. , Well wood, G.W. and J.W. Wilson. 1965. R e l a t i o n s h i p between c e r t a i n i n t r a - i n c r e m e n t p h y s i c a l measurements in D o u g l a s - f i r . Tech. Sect. Pulp and Pap. Mag. o f Canada 66(9):T475-T483. Isebrands, J.G., Einspahr, D.W., Phelps, J.E. and M.B. C r i s t . 1982. K r a f t p u lp and paper p r o p e r t i e s o f j u v e n i l e h y b r i d l a r c h grown under i n t e n s i v e c u l t u r e . Tappi 65(3):122-126. and CM. Hunt. 1975. Growth and wood p r o p e r t i e s o f rapid-grown Japanese l a r c h . Wood and F i b e r 7(2):119-128. Jackson, M. and R.A. Megraw. 1986. Impact o f j u v e n i l e wood on pulp and paper p r o d u c t s . Proc. A T e c h n i c a l Workshop: J u v e n i l e wood - What Does i t Mean t o F o r e s t Management and F o r e s t Products? F.P.R.S. S.A.F. Bellingham, Wa. pp. 75-81. Jo z s a , L.A. and R.M. K e l l o g g . 1986. An e x p l o r a t o r y study o f the d e n s i t y and annual r i n g weight t r e n d s i n f a s t - g r o w t h c o n i f e r o u s woods in B r i t i s h Columbia. F o r i n t e k Canada Corp., Vancouver, B.C. Tech. Rep. 43 pp. and E.P. Swan. 1986. B a s i c Wood p r o p e r t y v a r i a t i o n i n second-growth D o u g l a s - f i r . Extended A b s t r a c t s - Second-growth D o u g l a s - f i r : I t s U t i l i z a t i o n and Management f o r Value. F o r i n t e k Canada Corp., Vancouver, B.C. pp. 6-9. K e l l o g g , R.M. 1982. Coming t o g r i p s with wood q u a l i t y . F o r e s t r y Chron. 58(6):254-257. . 1986. A task f o r c e approach t o our changing r e s o u r c e . Proc. 47349. Managing and Marketing the Changing Resource. F.P.R.S. Conference, F o r t Worth, Texas. pp. 64-68. 83 K e l l o g g , R.M. and R.W. Kennedy. 1986. I m p l i c a t i o n s o f D o u g l a s - f i r wood q u a l i t y r e l a t i v e t o p r a c t i c a l end use. Proc. Symp. on D o u g l a s - f i r : Stand Management f o r the Future. Univ. Wa., S e a t t l e . pp. 97-102. Kennedy, R.W. and J.M. Jaworsky. 1960. V a r i a t i o n s i n c e l l u l o s e content o f D o u g l a s - f i r . Tappi 43(1):25-27. and J.M. Warren. 1969. W i t h i n - t r e e v a r i a t i o n i n p h y s i c a l and chemical p r o p e r t i e s o f D o u g l a s - f i r . Proc. I.U.F.R.O. Second World C o n s u l t a t i o n o f F o r e s t Tree Breeding. F.A.O., Rome. pp. 394-417. K i r k , D.G., Breeman, L.G. and B.J. Z o b e l . 1972. A p u l p i n g e v a l u a t i o n o f j u v e n i l e l o b l o l l y p i n e . Tappi 55(11):1600-1604. K l i n k a , K., Nuszdorfer, F.C. and L. Skoda. 1979. B i o g e o c l i m a t i c u n i t s o f c e n t r a l and southern Vancouver I s l a n d . P r o v i n c e o f B.C. M.O.F. I.S.B.N. 0-7719-8213-5. 120 pp. Kozlowski, T.T. 1971. Growth and Development o f T r e e s . Academic Press, N.Y. V o l . I. pp. 1-93, V o l . I I . pp. 1-63. Krahmer, R.L. 1966. V a r i a t i o n s o f s p e c i f i c g r a v i t y i n western hemlock t r e e s . Tappi 49(5):227-229. . 1986. Fundamental anatomy o f j u v e n i l e and mature wood. Proc. A T e c h n i c a l Workshop: J u n v e n i l e Wood - What does i t Mean t o F o r e s t Management and F o r e s t Products? F.P.R.S. S.A.F. Bellingham, Wa. pp. 12-16. Larson, P.R. 1962. A b i o l o g i c a l approach t o wood q u a l i t y . Tappi 45(6):443-448. . 1963. M i c r o s c o p i c wood c h a r a c t e r i s t i c s and t h e i r v a r i a t i o n s with t r e e growth. R e p r i n t f o r work group on wood q u a l i t y . I.U.F.R.O. Mimeo. 20 pp. . 1964. Some i n d i r e c t e f f e c t s o f environment on wood fo r m a t i o n . In. The Formation o f Wood in F o r e s t T rees. M. Zimmermann, Ed. Academic P r e s s , N.Y. pp. 345-365. 84 Larson, P.R. 1965. Stem form o f young Lar i x as In f l u e n c e d by wind and pruning. F o r e s t S c i . 11(4):412-424. . 1969. Wood form a t i o n and the concept o f wood q u a l i t y . Yale Univ. Sch. For. B u l l . No. 74. 54 pp. . 1973. The p h y s i o l o g i c a l b a s i s f o r wood s p e c i f i c g r a v i t y i n c o n i f e r s . Proc. Div. 5. I.U.F.R.O., Stel1enbosch, South A f r i c a . pp. 672-680. L i t t l e f o r d , T.W. 1961. V a r i a t i o n o f s t r e n g t h p r o p e r t i e s w i t h i n t r e e s and between t r e e s i n a stand o f rapid-growth D o u g l a s - f i r . F o r e s t Prod. Lab. o f Can. Rep. V-1028. 20 pp. Loo, J.A., Tauer, C.G. and R.W. McNew. 1985. Genetic v a r i a t i o n i n the time o f t r a n s i t i o n from j u v e n i l e t o mature wood i n l o b l o l l y pine (Pinus taeda L . ) . S i l v a e Genetica 34(1):14-19. McKimmy, M.D. 1966. A v a r i a t i o n and h e r e t a b i 1 i t y study o f wood s p e c i f i c g r a v i t y i n 46-year-old D o u g l a s - f i r from known seed sources. Tappi 49(12):542-549. . 1986. The e f f e c t o f f o r e s t management p r a c t i c e s on wood p r o p e r t i e s . Proc. A T e c h n i c a l Workshop: J u v e n i l e Wood - What Does i t Mean t o Fo r e s t Management and F o r e s t Products? F.P.R.S. S.A.F. Bellingham, Wa. pp. 35-49. and R.K. Campbell. 1982. Gen e t i c v a r i a t i o n i n the wood d e n s i t y and r i n g width t r e n d i n c o a s t a l D o u g l a s - f i r . S i l v a e G e n e t i c a 31(2-3):43-51. Marts, R.W. 1949. E f f e c t o f crown r e d u c t i o n on ta p e r and d e n s i t y i n long l e a f p i n e . South Lumberman 179:206-209. Megraw, R.A. 1985. Wood Q u a l i t y F a c t o r s i n L o b l o l l y Pine - The Influence o f Tree Age, P o s i t i o n i n Tree and C u l t u r a l p r a c t i c e on Wood S p e c i f i c G r a v i t y , F i b e r Length and F i b r i l Angle. Tappi P r e s s , A t l a n t a , Ga. 88 pp. . 1986. D o u g l a s - f i r wood p r o p e r t i e s . Proc. Symposium on D o u g l a s - f i r Stand Management f o r the Future. Univ. Wa., S e a t t l e . pp.81-95. 85 Megraw, R.A. and W.T. Nearn. 1972. D e t a i l e d D.B.H. d e n s i t y p r o f i l e o f s e v e r a l t r e e s from D o u g l a s - f i r f e r t i l i z e r / t h i n n i n g p l o t s . Proc. Symp. on E f f e c t o f Growth A c c e l e r a t i o n on P r o p e r t i e s o f Wood. U.S.D.A. F o r e s t Prod. Lab., Madison, Wi. 12 pp. Meylan, B.A. 1968. Cause o f high l o n g i t u d i n a l shrinkage in wood. F o r e s t Prod. J . 18(4):75-78. M i t c h e l l , K.J. 1969. S i m u l a t i o n o f the growth o f even-aged stands o f white spruce. Yale Univ. Sch. For. B u l l . No. 7. 47 pp. . 1975. Dynamics and s i m u l a t e d y i e l d o f D o u g l a s - f i r . F o r e s t S c i . Mono. 17. 39 pp. . 1980. D i s t a n c e dependent i n d i v i d u a l t r e e stand models: Concepts and a p p l i c a t i o n s . Proc. Workshop in F o r e c a s t i n g F o r e s t Stand Dynamics. School o f F o r e s t r y , Lakehead Univ., Thunder Bay, Ont. pp. 100-137. and I.R. Cameron. 1985. Managed stand y i e l d t a b l e s f o r c o a s t a l D o u g l a s - f i r : I n i t i a l d e n s i t y and precommercial t h i n n i n g . B.C. M i n i s t r y o f F o r e s t s Research Branch. Land Management Rep. ISSN 0702-9861. No. 31. 69 pp. Moody, R.C. 1970. T e n s i l e s t r e n g t h o f f i n g e r j o i n t s i n p i t h - a s s o c i a t e d and n o n - p i t h - a s s o c i a t e d southern pine lumber. U.S.D.A. For. Ser. Res. Pap. F.P.L. 138. F o r e s t Prod. Lab., Madison, Wis. 11 pp. N o r t h c o t t , P.L. 1957. Is s p i r a l g r a i n t h e normal growth p a t t e r n ? F o r e s t r y Chron. 33(4):335-352. O l i v e r , C D . 1986. S i l v i c u l t u r e and j u v e n i l e wood. Proc. A T e c h n i c a l Workshop: J u v e n i l e Wood - What Does i t Mean t o F o r e s t Management and F o r e s t Products? F.P.R.S. S.A.F. Bellingham, Wa. pp. 29-34. Owens, J.N. 1968. I n i t i a t i o n and development o f leaves i n D o u g l a s - f i r . Can. J . Bot. 46:271-278. Panshin, A.J. and C. de Zeeuw. 1980. Textbook o f Wood Technology. Fourth E d i t i o n . McGraw-Hill Book Co., N.Y. pp. 201-240. 86 Parker, M.L. and L.A. Jo z s a . 1973. X-ray scanning machine f o r t r e e - r i n g and d e n s i t y a n a l y s i s . Wood and F i b e r 5(3):192-197. Parker, M.L., Schoor1emmer, J . and L . J . C a r v e r . 1973. A computerized scanning densitometer f o r automatic r e c o r d i n g o f t r e e - r i n g width and d e n s i t y data from x-ray n e g a t i v e s . Wood and F i b e r 5(3):237-248. Pa u l , B.H. 1950. Wood q u a l i t y i n r e l a t i o n t o s i t e q u a l i t y o f second-growth D o u g l a s - f i r . J . F o r e s t r y 48(3):175-179. . 1957. J u v e n i l e wood i n c o n i f e r s . U.S.D.A. F o r e s t Prod. Lab. Rep. 2094. 6 pp. . 1960. The j u v e n i l e core i n c o n i f e r s . Tappi 43(1):1-2. Pearson, E.S. and H.O. H a r t l e y . 1954. B i o m e t r i k a . Tables f o r S t a t i s t i c i a n s , V o l . 1. Cambridge Univ. P r e s s , N.Y. pp. 290-299. Pearson, R.G. and R.C. G i l more. 1971. C h a r a c t e r i s t i c s o f the s t r e n g t h o f j u v e n i l e wood o f l o b l o l l y p i n e (Pinus taeda L . ) . F o r e s t Prod. J . 21(l):23-30. . 1980. E f f e c t o f fast-growth r a t e on the mechanical p r o p e r t i e s o f l o b l o l l y p i n e . F o r e s t Prod. J . 30(5):47-54. and B.E. Ross. 1984. Growth r a t e and bending p r o p e r t i e s o f s e l e c t e d l o b l o l l y p i n e s . Wood and F i b e r S c i . 16(l):34-47. P e r r y , T.O. and CW. Wang. 1958. V a r i a t i o n i n the s p e c i f i c g r a v i t y o f s l a s h pinewood and i t s g e n e t i c and s i l v i c u l t u r a l i m p l i c a t i o n s . Tappi 41(4):178-180. Plumptre, R.A. and S. A u s t i n . 1978. The i n f l u e n c e o f pruning on the d e n s i t y and r a t e o f growth o f Pi nus patu1 a. Proc. I.U.F.R.O. Conf. Wood Q u a l i t y and T r o p i c a l S p e c i e s . F.W. Tamolang, Ed. pp. 351-370. Polge, H. 1964. The j u v e n i l e wood o f c o n i f e r s . Rev. For. Franc. 16:474-505. 87 Polge, H., K e l l e r , R. and F. T h i e r c e l i n . 1973. I n f l u e n c e de l'elagage de branches v i v a n t e s sur l a s t r u c t u r e des aeroissements annuels et sur quelques c h a r a c t e r i s t i q u e s du b o i s de douglas et de g r a n d i s . Ann. S c i . For. 30:127-140. Reeb, D. 1984. Influence o f s p a c i n g and a r t i f i c i a l p runing on the p r o d u c t i o n o f clearwood o f D o u g l a s - f i r . Unpub. M.F. T h e s i s . Dept. o f F o r e s t r y , Univ. B.C. 255 pp. Rendle, B.J. 1958. A note on j u v e n i l e and a d u l t wood. I.A.W.A. News B u l l . 2:1-6. . 1959. Fast-grown c o n i f e r o u s timber - some anatomical c o n s i d e r a t i o n s . Quart. J . F o r e s t r y 53:116-122. . 1960. J u v e n i l e and a d u l t wood. J . Inst, o f Wood S c i . 5:58-61. and E.W. P h i l l i p s . 1957. The e f f e c t o f r a t e o f growth ( r i n g width) on the d e n s i t y o f softwoods. F o r e s t r y 31:113-120. Reukema, D.L. 1959. M i s s i n g annual r i n g s i n branches o f young growth D o u g l a s - f i r . E c o l . 40:480-482. . 1961. Crown development and i t s e f f e c t on stem growth o f s i x D o u g l a s - f i r . J . F o r e s t r y 59(5):370-371. Richardson, S.D. 1961. A b i o l o g i c a l b a s i s f o r sampling in s t u d i e s o f wood p r o p e r t i e s . Tappi 44(3):170-173. Richardson, S.D. and J.M. Dinwoodie. 1960. S t u d i e s on the p h y s i o l o g y o f xylem development. I. The e f f e c t o f n i g h t temperature on t r a c h e i d s i z e and wood d e n s i t y i n c o n i f e r s . J . Int. Wood. S c i . 6:3-13. Ru t t e r , A.J. 1957. S t u d i e s i n the growth o f young p l a n t s o f Pinus s y 1 v e s t r i s L. I. The annual c y c l e o f a s s i m i l a t i o n and growth. Ann. Bot. 21(83):399-426. S a s t r y , C B . and R.W. Well wood. 1971. I n d i v i d u a l t r a c h e i d weight-1ength r e l a t i o n s h i p s i n D o u g l a s - f i r . Tappi 54(10):1686-1690. 88 Schmidt, J.D. and W.J. Smith. 1961. Wood q u a l i t y e v a l u a t i o n and improvement in Pinus c a r i b a e a Morelet. Queensland For. Serv. Res. Note No. 15. 59 pp. S e n f t , J.F., Bendtsen, B.A. and W.L. G a l l i g a n . 1985. Weak wood, fast-grown t r e e s make problem lumber. J . F o r e s t r y 83(8):476-484. , Quanci, M.J. and B.A. Bendtsen. 1986. P r o p e r t y p r o f i l e o f 6 0 - y e a i — o l d D o u g l a s - f i r . Proc. A T e c h n i c a l Workshop: J u v e n i l e wood - What Does i t Mean t o F o r e s t Management and F o r e s t Products? F.P.R.S. S.A.F. Bellingham, Wa. pp. 17-28. Shiokura, T. 1984. The c l a s s i f i c a t i o n o f J u v e n i l e wood and i t s perimeter i n c o n i f e r o u s t r e e s . Proc. P a c i f i c Reg. Wood Anat. Conf. Tsukuba, I b a r i k i , Japan. pp. 76-78. Smith, D.M. 1954. Maximum moisture content method f o r determining s p e c i f i c g r a v i t y o f small wood samples. U.S.D.A. For. Serv., F o r e s t Prod. Lab. Rep. 2014. 8 pp. . 1968. Wood q u a l i t y o f l o b l o l l y p ine a f t e r t h i n n i n g . U.S.D.A. F o r e s t Prod. Lab. Madison, Wi. Res. Pap. F.P.L. 89. 10 pp. Smith, J.H.G., Heger, L. and J . H e j j a s . 1966. P a t t e r n s i n growth o f earlywood, latewood and percentage latewood determined by complete a n a l y s i s o f 18 D o u g l a s - f i r t r e e s . Can. J . Botany. 44:453-466. , Ker, J.W. and C s i z m a z i a , J . 1961. Economics o f r e f o r e s t a t i o n o f D o u g l a s - f i r , western hemlock and western redcedar i n the Vancouver f o r e s t d i s t r i c t . Fac. o f F o r e s t r y , Univ. o f B.C. For. B u l l e t i n No. 3. 144 pp. Smith, R.W. and D.G. B r i g g s . 1986. J u v e n i l e wood: Has i t come o f age? Proc. A T e c h n i c a l Workshop: J u v e n i l e Wood - What Does i t Mean t o F o r e s t Management and F o r e s t Products? F.P.R.S. S.A.F. Bellingham, Wa. pp. 5-9. T a y l o r , F.W., Wang, E.I.C., Yanchuk, A. and M.M. Micko. 1982. S p e c i f i c g r a v i t y and t r a c h e i d length v a r i a t i o n s o f white spruce i n A l b e r t a . Can. J . F o r e s t r y Res. 12:561-566. 89 Trendelenberg, R. 1935. V a r i a t i o n s i n the d e n s i t y o f important c o n i f e r o u s timbers due t o l o c a l i t y , h a b i t a t , and d i f f e r e n c e i n i n d i v i d u a l t r e e s . Z e i t s c h r i f t des V e r e i n e s Deutscher Ingenieure. Imp. For. I n s t . Univ. Oxford. T r a n s l a t i o n No. 1. 79(4):85-89. T u r n b u l l , J.M. 1937. V a r i a t i o n s i n s t r e n g t h o f pine t i m b e r s . S. A f r i c a n J . S c i . 33:653-682. Wang, E.I.C. and M.M. Micko. 1984. Wood q u a l i t y o f white spruce from n o r t h - c e n t r a l A l b e r t a . Can. J . F o r e s t r y Res. 14:181-185. Wangaard, F.F. and F.V. Zumwalt. 1949. Some s t r e n g t h p r o p e r t i e s o f second-growth D o u g l a s - f i r . J . F o r e s t r y 47(1):18-24. Wareing, P.F. 1958. The p h y s i o l o g y o f cambial a c t i v i t y . J . I n s t . Wood S c i . 1:34-42. Wei 1 wood, R.W. 1952. The e f f e c t o f s e v e r a l v a r i a b l e s on the s p e c i f i c g r a v i t y o f second-growth D o u g l a s - f i r . F o r e s t r y Chron. 28(2):34-42. . 1960. S p e c i f i c g r a v i t y and t r a c h e i d length v a r i a t i o n s i n second-growth western hemlock. J . F o r e s t r y 58(5):361-368. and P.E. J u r a z s . 1968. V a r i a t i o n i n sapwood t h i c k n e s s , s p e c i f i c g r a v i t y and t r a c h e i d length i n western redcedar. F o r e s t Prod. J . 18(12):37-46. and J.H.G. Smith. 1962. V a r i a t i o n i n some important q u a l i t i e s o f wood from young D o u g l a s - f i r and hemlock t r e e s . Fac. o f For., Univ. B r i t . C o l . , Vancouver. Res. Pap. No 50. 15 pp. Wilcox, H. 1962. Cambial growth c h a r a c t e r i s t i c s . J_n Tree Growth. T.T. Kozlowski, Ed. Ronald P r e s s , N.Y. pp. 57-88. Wilson, B.F. 1984. The Growing Tree. The U n i v e r s i t y o f Massachusetts P r e s s . 138 pp. Wodzicki, T. 1960. I n v e s t i g a t i o n on the k i n d o f Lar i x po1 o n i c a Rac. wood formed under v a r i o u s p h o t o p e r i o d i c c o n d i t i o n s . I. P l a n t s growing under n a t u r a l c o n d i t i o n s . A c t a . Soc. Bot. P o l o n i a e . 29:713-730. 90 Wood, F.F. and J . Bryan. 1960. The s i l v i c u l t u r e and q u a l i t y o f S i t k a spruce grown i n Great B r i t a i n . Proc. F i f t h World F o r e s t . Cong. Univ. Wa. S e a t t l e . Vol 111:1372-1374. Woodfin, R.O. J r . 1969. S p i r a l g r a i n p a t t e r n s i n c o a s t a l D o u g l a s - f i r . F o r e s t Prod. J . 19(l):53-60. Yang, K.C., Benson, C A . and J.K. Wong. 1986. D i s t r i b u t i o n o f j u v e n i l e wood i n two stems o f Lar i x 1ar i c i na. Can. J . F o r e s t r y Res. 16:1041-1049. Zob e l , B.J. 1984. The changing q u a l i t y o f the world wood supply. Wood S c i . Techno 1. 18:1-17. and R.C K e l l i s o n . 1972. S h o r t - r o t a t i o n f o r e s t r y i n the southeast. Tappi 55(8):1205-1208. and D.G. K i r k . 1972. Proc. Symp. on the E f f e c t o f Growth A c c e l e r a t i o n on the P r o p e r t i e s o f Wood. U.S.D.A. F.P.L. Madison, Wi. pp. M1-M20. and R.L. McElwee. 1958. Natural v a r i a t i o n i n wood s p e c i f i c g r a v i t y o f l o b l o l l y p i n e and an a n a l y s i s o f c o n t r i b u t i n g f a c t o r s . Tappi 41(4):158-161. , Matthias, M., Roberds, J.H. and R.C. K e l l i s o n . 1968. Moisture content o f southern pine t r e e s . School For. Res. N.C S t a t e Univ. R a l e i g h , N.C Tech. Rep. No. 37. 44 pp. and J.T. T a l b e r t . 1984. A p p l i e d F o r e s t Tree Improvement. John Wiley and Sons, Inc. pp. 376-413. , Webb, C. and F. Henson. 1959. Core or j u v e n i l e wood o f l o b l o l l y and s l a s h p i n e t r e e s . Tappi 42(5):345-356. 91 TabIt 1. Douglas-fir stand characteristics. Location Coordinates Biogeo- Organization Ag* Height Crown Crow 6.B.H. Density Basal Douglas- Latitude Longitude cliaatic Sad. Length (stei/ha) Area fir Zone (B.H.) (•) (•) (•) (cn) ha) (• sq/ Z ha) (1) (2) (2) (2) (2) (2) (3) (3) (3) o o Ladysnith 49 OO'H 123 52'W CDFb Crovn Forest 54 42.2 S.7 17.3 54.5 Industries o o Cassidy 49 04'N 123 55'y CDFb MacMillan 58 41.7 4.6 17.7 57.8 (54 46.1 100 Bloedel o o Caipbell 50 OO'N 125 17'W CDFb B.C. Forest 53 38.8 4.2 17.5 52.7 395 43.3 100 River Products o o Lake 48 48'N 124 09'W CWHal C.I.P. Inc. 39 33.6 3.4 17.1 38.4 381 42.1 43 Covichan o o Lizard 48 35'N 124 08'W CWHbl B.C. Forest 46 35.6 3.3 18.1 45.8 705 50.7 34 Late Products o o Jordan 48 24>N 124 08'W CWHbl - Western Forest 52 40.3 3.4 15.9 52.5 523 51.8 40 River CWHal Products o o Haney 49 17'N 122 30'W CWHa2 - U.B.C. Research 48 70 CWHb2 Forest o o Hart 50 02'N 125 20'H CDFb B.C. Ministry 37 100 of Forests o o Henekay 50 02'N 125 19'W CDFb B.C. Ministry 35 100 of Forests (1) Biogeoclinatic Zone Classification (Klinka et a l . , 1979). CDFb: Coastal Douglas-fir - vetter subzone CWHal: Coastal Western Henlock - Vancouver Island, wetter subzone CWHa2: Coastal Western Henlock - Pacific Range, vetter subzone CWHbl: Coastal Western Henlock - Windvard Subnontane Naritine, drier subzone CWHb2: Coastal Western Henlock - Windward Montana Haritine, drier subzone (2) Based on the average of ten dominant and codoninant trees per stand. (3) Based on prist cruise information. Table 2. Saaple tree character is t ics . Sample Location Age D.B.H. Height Col lect ion Contents Tree Mo. (B.H.) Bate (ca) (a) IAS Ladysaith 56 46.8 37.0 Nay, 19B5 fecond-grovth IA7 Ladysaith SI 46.1 37.0 Nay, 1985 second-growth I K Cassidy 53 49.2 44.7 Hay, 1983 second-growth IBM Cassidy 63 49.1 36.1 Hay, 1985 second-grovth 1C1 Caapbell River 54 47.3 40.0 Hay, 1985 second-grovth IC6 Caapbell River 53 49.1 38.0 Hay, 1985 SKond-growth 1D5 Lake Covichan 33 45.5 32.0 June, 1985 second-grovth I K lake Covicha* 35 43.2 29.5 Jane, 1985 second-growth 1E3 Lizard Lake 43 39.4 35.0 June, 1985 second-grovth IE8 Lizard Lake 47 68.2 36.0 Jane, 1985 second-growth 1F7 Jordan River 53 57.5 41.5 June, 1985 second-grovth trio Jordan River 52 52.7 39.0 Jane, 1985 second-grovth RFl Haney 21 26.8 23.3 A p r i l , 1985 SKond-grovth RF2 Haney 51 68.3 31.7 A p r i l , 1985 second-growth pruned RF3 Haney 45 44.0 29.7 January, 1986 second-grovth pruned CRl Hart 37 19.8 16.8 October, 1985 plantation-grown CR2 Heaekay 35 36.7 31.5 October, 1985 plantation-grown 93 Table 3. Tree crovn characteristics. Saaple Location Height Age Crovn Crovn Base Crovn Average Average Average Crovn Coefficient Tree No. (B.H.) Length Height Base Crovn Crovn Crovn Radius Values Age Length Height Age (BL) (a) (a) (a) (L) (a) (a) (b) (a) (1) (1) (1) (2) (2) (2) IAS Ladysaith 37.0 56 14.8 22.2 28 14.3 22.7 27 4.65 3.952 1A7 Ladysaith 37.0 51 13.6 23.4 29 10.0 27.0 23 4.68 4.956 1B6 Cassidy 44.7 53 21.9 22.8 28 13.0 31.7 17 4.23 3.806 IBi l Cassidy 36.1 63 15.3 20.8 35 15.1 21.3 34 4.40 3.625 1CI Caapbell River 40.0 54 15.9 24.1 29 13.8 26.4 26 3.61 3.612 1C6 Caapbell River 30.0 53 13.2 24.8 24 11.1 26.9 19 3.70 3.701 IBS Lake Covichan 32.0 33 16.9 IS.l 20 12.0 19.9 13 3.47 3.262 I K Lake Covichan 29.5 35 11.3 18.2 16 8.5 21.0 13 3.40 3.966 1E3 Lizard Lake 35.0 43 17.9 17.1 21 13.2 22.2 17 4.01 3.588 1E8 Lizard Lake 36.0 47 14.4 21.6 25 8.8 27.2 17 3.66 4.204 1F7 Jordan River 41.5 53 18.1 23.4 28 7.7 33.8 15 3.24 4.080 1F10 Jordan River 39.0 52 14.2 24. B 29 8.7 30.3 21 2.91 3.362 Rf 1 Haney 23.3 21 14.3 9.0 12 8.1 15.2 6 2.64 3.213 RF2 Haney 31.7 51 21.0 10.7 39 - - - - - RF3 Haney 29.7 45 18.1 11.6 33 - - - - - CR1 Hart 16.8 37 6.7 9.4 22 3.9 12.8 16 1.4B 3.239 CR2 Heaekay 31.5 35 12.8 18.7 19 5.6 25.9 9 2.80 4.420 Averages (3) 34.5 46 14.7 19.7 24 10.2 24.2 18 3.50 3.799 (1) Base of the live crovn height observed as the lovest part of the crovn with three or tore live branches. (2) Average crovn height estiaated as tree height ainus L, where L is given by the following equation: BL / (bd) L = c ( e -1) L ' crown length or distance froa terainal leader to branch base c e coefficient describing the shape of the crovn (estiaated for Douglas-fir as (.1 a) BL - crown radiis b - coefficient relating branch growth to height growth d 8 coefficient coapensating for branch crooks (estiaated for Douglas-fir as 0.975) e =2.71828 (3) Overall averages not including pruned trees RF2 and RF3. 94 Table 4. Sunnary of relative density values for sections at breast height (B.H.). Satple Location Height Nunber of Relative Density Tree Ho. 6rowth (•) Increaents Mean S.D. Haxiaua Hiniaua IAS Ladysnith 1.30 56 .542 .062 .640 .380 1A7 Ladysnith 1.30 51 .563 .057 .660 .430 IBS Cassidy 1.30 53 .520 .055 .650 .420 1BU Cassidy 1.30 63 .543 .057 .680 .430 1C1 Catpbeil River 1.30 54 .558 .053 .660 .440 1C6 Catpbell River 1.30 53 .566 .062 .700 .440 IDS Lake Covicban 1.30 33 .474 .034 .540 .420 1D6 Lake Covichan 1.30 35 .488 .062 .600 .380 1E3 Lizard Lake 1.30 43 .595 .049 .680 .500 1E8 Lizard Lake 1.30 47 .487 .044 .590 .390 1F7 Jordan River 1.30 53 .551 .061 .650 .430 1F10 Jordan River 1.30 52 .537 .060 .640 .430 RF1 Haney 1.30 21 .429 .041 .530 .360 CR1 Hart 1.30 37 .536 .070 .670 .410 CR2 Henekay 1.30 35 .444 .039 .510 .340 A l l Trees 1.30 46 .523 .054 .625 .413 95 Table 5. Suaaary of relative density values for sections saapled at 20 percent of total height. Saaple Tree No. Location Height (a) Nuaber of firovth Increments Mean Relative Density S.D. Haxiaua Hiniaua 1A5 Ladysaith 7.55 47 .468 .063 .620 .360 1A7 Ladysaith 7.20 44 .520 .071 .650 .370 1B6 Cassidy 8.55 45 .504 .055 .590 .400 1BU Cassidy 7.10 53 .489 .037 .590 .410 1C1 Caapbell River 8.00 47 .494 .049 .570 .390 1C6 Caapbell River 7.60 46 .502 .059 .600 .380 1D5 Lake Covichan 6.40 27 .482 .039 .560 .430 1D6 Lake Covichan 5.90 29 .437 .043 .520 .350 1E3 Lizard Lake 7.10 32 .498 .03B .590 .440 1E8 Lizard Lake 7.20 41 .463 .057 .610 .360 1F7 Jordan River 8.30 46 .490 .061 .610 .380 IF 10 Jordan River 7.80 46 .485 .052 .570 .390 RF1 Haney 4.54 17 .423 .035 .500 .380 Cftl Hart 3.34 34 .543 .076 .680 .420 CR2 Heaekay 6.40 29 .483 .049 .580 .370 A l l Trees 6.85 39 .485 .052 .589 .389 96 Table 6. Suaaary of relative density values for sections saapled at 40 percent of total height. Saaple Location Height Nuaber of Relative Density Tree Ho. Srovth (a) Increments Hean S.D. Haxiaua Hiniaua IAS Ladysaith 14.90 40 .445 .049 .540 .370 IA7 Ladysaith IS. 10 39 .480 .045 .570 .380 IBS Cassidy 17.20 32 .495 .042 .570 .420 m i Cassidy 14.20 45 .478 .033 .580 .410 1C1 Caapbell River 16.00 39 .468 .032 .520 .400 1C6 Caapbell River 15.20 36 .496 .040 .560 .430 IDS Lake Covichan 12.80 20 .475 .035 .550 .430 ID6 Lake Covichan 11.90 23 .450 .037 .550 .400 1E3 Lizard Lake 14.00 26 .450 .024 .510 .390 IE8 Lizard Lake 14.40 33 .456 .039 .530 .370 1F7 Jordan River 16.40 38 .473 .040 .570 .420 IF10 Jordan River 15.90 39 .472 .030 .530 .410 RF1 Haney 9.00 13 .398 .054 .500 .340 Cfil Hart S.I0 31 .486 .069 .620 .390 CR2 Heaekay 25.77 22 .488 .028 .540 .440 A l l Trees 13.59 32 .467 .040 .549 .400 97 Tab 1 e 7. Sumry of relative density values for sections sampled at 60 percent of total height. Saaple Tree No. Location Height (a) Nuaber of 6rovth Increments Hean Relative Density S.D. Haximua Hinimum 1A5 Ladysaith 22.2 28 .460 .038 .560 .400 1A7 Ladysaith 22. S 31 .479 .054 .670 .410 IB6 Cassidy 25.8 24 .478 .027 .540 .440 1611 Cassidy 21.3 29 .479 .031 .560 .430 1C1 Caapbell River 24.1 29 .448 .023 .510 .410 IC6 Caapbell River 22.8 25 .478 .034 .550 .410 IDS Lake Covichan 19.2 14 .456 .034 .510 .390 106 Lake Covichan 17.7 17 .428 .041 .530 .360 1E3 Lizard Lake 21.0 17 .417 .017 .450 .400 IE8 Lizard Lake 21.6 25 .420 .034 .500 .360 1F7 Jordan River 24.9 22 .497 .056 .650 .430 IF 10 Jordan River 23.4 26 .495 .026 .550 .460 RF1 Haney 13.6 8 .445 .042 .510 .400 CRl Hart 9.9 17 .485 .025 .540 .450 CR2 Heaekay 24.8 20 .459 .048 .630 .400 Al l Trees 20.6 22 .462 .035 .551 .410 98 Table 8. Suttary of relative density values for sections sanpled at 80 percent of total height. Saaple Tree No. Location Height (n) Nunber of Grovth Increments Hean Relative Density S.D. Haxinun Hininun IAS Ladysnith 29.4 13 .440 .030 .510 .410 IA7 Ladysnith 29.9 18 .499 .038 .600 .450 I K Cassidy 36.1 12 .479 .052 .610 .420 IBM Cassidy 28.4 19 .488 .032 .570 .450 1C1 Canpbell River 32.0 15 .411 .015 .460 .400 1C6 Canpbell River 30.4 12 .499 .035 .560 .430 IDS Lake Covichan 25.6 8 .540 .027 .580 .500 1D6 Lake Covichan 23.6 8 .468 .027 .510 .420 1E3 Lizard Lake 28.0 9 .483 .031 .560 .450 1E8 Lizard Lake 28.8 14 .454 .030 .530 .420 1F7 Jordan River 33.7 14 .517 .058 .640 .450 If 10 Jordan River 31.2 19 .420 .042 .560 .430 Rf 1 Haney 18.2 4 .492 .025 .520 .460 CR1 Hart 13.4 7 .485 .040 .540 .430 CR2 Henekay 25.8 16 .493 .041 .590 .440 A l l Trees 27.6 13 .478 .035 .556 .437 99 Table 9. Sunaary of the distribution of relative density p r o f i l e s which showed no juvenile - nature wood transition. Section Ranter «f Height Juvenile Hood 6rovtn Increment Height Sections Hean S.I. Hai. Hin. Hean S.I. (tax. Hin. B.H. 1 1.30 - 1.30 1.30 21.00 - 21.00 21.00 201 1 4.54 - 4.54 4.54 17.00 - 17.00 17.00 401 6 10.83 3.31 14.40 5.10 23.67 7.37 33.00 13.00 602 15 20.59 4.26 25.80 9.95 22.13 6.50 31.00 8.00 801 IS 27.63 5.83 36.10 13.38 12.53 4.58 19.00 4.00 A l l Sections 38 20.99 8.58 36.10 1.30 18.42 7.45 33.00 4.00 100 Table 10. Transition determination by coaparing simple against segmented linear regression aodels on relative density p r o f i l e s . Sample Location Section Juvenile - Simple Linear Hodel 1 Segmented Linear Hodel 2 'F* Value •F" Prob. Tree Height Nature Hood No. Transition Hean Square Hean Square Age -3 -3 Hodel 1 / (years) D.F. ( i 10 ) D.F. ( x 10 ) Hodel 2 P > F 1A5 Ladysnith B.H. 22 50 2.081 48 1.623 1.281 0.20 201 28 41 1.971 39 1.857 1.061 0.42 401 25 23 1.660 21 1.480 1.121 0.40 1A7 Ladysnith B.H. 19 41 2.058 39 1.468 1.401 0.14 20Z 24 35 2.609 33 1.743 1.496 0.14 401 24 31 1.303 29 0.841 1.548 0.10 m Cassidy B.H. 16 44 1.302 42 1.129 1.153 0.32 201 17 35 0.751 33 0.666 1.128 0.37 40Z 18 24 0.564 22 0.542 1.055 0.40 1 BI 1 Cassidy B.H. 32 56 1.738 54 1.247 1.394 0.11 201 25 50 1.373 48 0.863 1.590 0.05 40Z 16 41 1.176 39 1.023 1.150 0.34 1C1 Campbell B.H. 19 47 1.182 45 0.915 1.292 0.19 River 20Z 25 41 0.868 39 0.597 1.454 0.02 40Z 29 32 0.482 30 0.463 1.042 0.42 IC6 Campbell B.H. 15 47 2.258 45 1.980 1.141 0.33 River 20Z 35 41 2.247 39 1.813 1.239 0.26 401 26 31 2.284 29 1.006 2.270 0.00 1D5 Lake B.H. 19 30 0.861 28 0.844 1.020 0.43 Covichan 20Z 20 23 0.759 21 0.712 1.070 0.44 101 Table 10. Transition determination by comparing simple against segaented linear regression models on relative density profiles (cont.). Saaple Location Section Juvenile - Simple Linear Model 1 Segaented Linear Model 2 V Value •r Prob. Tree Height Nature Hood No. Transition Mean Square Mean Square Age -3 -3 Model 1 / P > F (years) D.F. ( x 10 ) D.F. ( x 10 ) Model 2 106 Lake B.H. 17 30 1.015 28 0.878 1.156 0.35 Covichan 20Z IS 24 0.661 22 0.542 1.220 0.31 1E3 Lizard B.H. 28 32 1.069 30 0.985 1.085 0.41 Lake 20Z 26 25 0.785 23 0.762 1.031 0.47 401 11 19 0.405 17 0.293 1.378 0.25 IE8 Lizard B.H. 34 41 I.0S5 39 0.930 1.134 0.35 Lake 20Z 26 31 1.220 29 1.019 1.197 0.32 1F7 Jordan B.H. 25 45 1.633 43 0.801 2.037 0.01 River 201 25 39 1.086 37 0.422 2.573 0.00 40Z 24 28 1.418 26 0.852 1.664 0.10 1F10 Jordan B.H. 24 49 1.338 47 0.985 1.358 0.15 River 20Z 22 39 1.465 37 1.023 1.425 0.14 401 15 35 0.557 33 0.448 1.244 0.27 CXI Hart B.H. 20 28 1.576 26 1.331 1.183 0.2S 20Z IS 22 1.905 20 1.019 1.873 0.07 CR2 Heaekay B.H. 23 24 0.930 22 0.797 1.166 0.32 20Z 13 23 0.866 21 0.798 1.087 0.42 102 TabI* 11. Sutury of tht distribution of relative density profiles which shoved juvenile - nature vood transition. Section Nunber of Height Total Nunber No. of Juvenile-Nature Mood Height Sections (•) of 6rovth Increments Trans. Growth Increments Hean S.D. Hai. Him. Mean S.D. Has. Hin. Hean S.D. Hax. Hin. B.H. 14 1.30 - 1.30 1.30 47.50 9.33 63.00 33.00 22.36 5.77 34.00 15.00 201 14 7.03 1.03 8.55 3.34 40.43 8.44 53.00 27.00 22.86 5.72 35.00 13.00 401 9 15.43 1.04 17.20 14.00 37.11 5.40 45.00 26.00 20.89 6.05 29.00 11.00 All Sections 37 6.91 5.59 17.20 1.30 42.30 9.07 63.00 26.00 22.18 5.71 35.00 11.00 103 Table 12. Suuary of the relative density values of the profiles which shoved no juvenile - nature wood transition. Section Height Nuaber of Sections Nuaber of Growth Increaents Relative tensity Juvenile Hood Nature Hood Total Juvenile Hood Hatare Wood Total Hean S.B. Hax. Hin. Hean S.B. Hax. Hin. Heaa S.B. Hax. Hin. B.H. 1 21.00 - 21.00 .429 .041 .530 .360 - .429 .041 .530 .360 201 1 17.00 - 17.00 .423 .035 .500 .380 - - - .423 .035 .500 .380 401 6 23.66 - 23.66 .459 .044 .548 .39S - .459 .044 .548 .395 60Z 15 22.13 - 22.13 .462 .035 .551 .410 - .462 .035 .551 .410 801 15 18.42 - 18.42 .481 .035 .556 .437 - .481 .03S .556 .437 All Sections i 38 18.42 18.42 .467 .031 .551 .416 .467 .031 .551 .416 104 Table 13. Suaaary of the relative density values of the profiles which showed juvenile - aature wood transition. Section Huaber of Average Hunter of Relative tensity Height Sections Growth Increaents Juvenile Hood Hature Hood Total Juvenile Hature Total Hean S.B. Max. Hin. Mean S.D. Max. Win. Mean S.D. Max. Min. Hood Hood I.H. 14 22.36 24.71 47.30 .491 .046 .601 .417 .563 .034 .630 .496 .529 .055 .634 .417 201 14 22.S6 17.57 40.43 .460 .046 .566 .389 .529 .032 .592 .474 .490 .054 .596 .389 401 9 20.89 16.22 37.11 .461 .037 .537 .406 .491 .027 .540 .439 .473 .037 .550 .403 All Sections 37 22.18 19.95 42.30 .472 .044 .572 .404 .533 .032 .594 .474 .501 .050 .599 .403 105 TABLE 14. Overall sunnary of relative density values for juvenile and nature wood. Section Nunber of Average Nunber of Relative Oensity ght Sections Growth Increaents Juvenile Hood Nature Hood Total Juvenile Hood Hatare Hood Total Hean S.D. Hai. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. B.H. IS 22.67 24.71 45.73 .487 .046 .596 .413 .563 .034 .630 .496 .523 .054 .625 .413 201 15 22.47 17.57 38*86 .457 .045 .561 .389 .529 .032 .592 .474 .465 .052 .589 .389 401 IS 22.00 16.22 31.73 .460 .040 .541 .401 .491 .027 .540 .439 .467 .040 .549 .400 601 IS 22.13 - 22.13 .462 .035 .551 .410 - .462 .035 .551 .410 801 IS 12.S3 12.53 .481 .035 .556 .437 . . . . .481 .035 .556 .437 All Sections 75 20.28 19.95 30.20 .469 .040 .561 .410 .533 .032 .594 .474 .483 .043 .547 .410 106 Table 15. Suaaary of sampled dead branch characteristics. Tret Number of Height Position Number of Number Branches (m) 6rovth Increments Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. IAS 5 17.8 4.218 22.2 12.2 13.4 5.983 20.0 6.0 1A7 7 (S.S 7.378 23.4 5.2 11.1 5.550 22.0 6.0 1B6 11 13.0 (.374 22.0 3.4 12.0 2.932 18.0 B.O 1811 13 11.2 ..037 20.8 2.4 18.3 S.360 26.0 11.0 1C1 10 17.4 5.316 24.1 8.0 16.5 4.648 24.0 10.0 IC6 11 16.6 4.576 24.1 10.5 14.2 4.051 22.0 9.0 IDS 9 8.3 4.431 1S.1 2.0 10.7 1.481 13.0 9.0 1D6 9 10.0 5.394 17.7 2.7 10.5 2.006 15.0 8.0 1E3 10 8.4 4.773 16.0 2.2 10.2 2.699 15.0 7.0 1E8 12 12.9 S.886 21.6 3.3 14.6 2.839 19.0 10.0 1F7 12 12.4 6.640 22.4 2.5 11.0 3.604 18.0 7.0 IF 10 11 13.9 6.311 23.4 4.2 8.4 2.383 13.0 6.0 A l l Trees 120 12.9 6.226 24.1 2.0 12.7 4.628 26.0 6.0 107 l ibit 16. Suaaary of lovest relative density values. Tree Hunter of Height Position Lovest Relative Density Nutber Sections (•) Number of 6rovth Increments Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1A5 S 1S.1 1A7 5 1S.2 1B6 5 17.8 1111 5 14.S 1C1 5 16.3 1C6 5 IS.S 1D5 S 13.1 1D6 5 12.1 1E3 5 14.3 1E8 3 14.7 1F7 S 16.9 1F10 S 1S.9 CR1 S 6.6 CR2 5 12.8 11.207 29.4 1.3 11.474 29.5 1.3 13.757 36.1 1.3 10.839 28.3 1.3 12.269 32.0 1.3 11.613 30.4 1.3 9.717 25.6 1.3 8.926 23.6 1.3 10.648 28.0 1.3 10.981 28.8 1.3 12.882 33.7 1.3 11.928 31.2 1.3 4.954 13.4 1.3 9.714 25.8 1.3 7.4 2.302 11.0 5.0 7.2 1.483 9.0 5.0 6.8 2.168 9.0 4.0 6.0 3.336 10.0 2.0 5.2 0.837 6.0 4.0 5.8 2.049 8.0 4.0 5.8 4.438 13.0 2.0 7.2 4.087 13.0 4.0 7.0 1.871 10.0 5.0 9.8 3.834 15.0 5.0 7.4 1.140 9.0 6.0 7.4 5.367 14.0 2.0 9.0 1.581 11.0 7.0 7.8 1.924 10.0 5.0 All Trees 70 14.3 10.229 36.1 1.3 7.1 2.904 15.0 2.0 108 Table 17. Differences between height of juvenile - nature wood transition point, height of crovn base and total height. Section Height Difference Between Transition Height Difference Between Transition Height Point and Crovn Base Point and'Total Height I Obs. Hean S.D. Hax. Hin. I Obs. Hean S.D. Hax. Hin. B.H. 12 10.25 3.802 17.22 8.09 14 18.95 5.875 28.97 8.65 20Z 12 8.71 3.404 13.23 2.52 14 18.51 4.324 23.54 7.23 401 9 3.85 3.280 6.72 -3.15 9 14.59 4.081 22.02 9.78 All Sections 33 7.95 4.311 17.22 -3.15 37 17.72 5.118 28.97 7.23 109 Tib It 18. Suaaary of height difference statist ics. f i rs t Height Second Height Nutter Height Difference (•) Heasureaent Heasuretent of Observations Hean S.B. Hax. Hin. Total height Live crovn base height IS 14.78 3.399 21.90 6.80 Total height Average crovn height IS 10.26 3.295 15.10 4.00 Average crovn height Live crovn base height 15 4.50 2.920 10.40 0.20 Total height Average transition A 14 12.63 3.835 18.76 7.13 Total height Average transition B 14 17.91 4.172 25.28 8.06 Average transition A Average transition B 14 5.28 4.388 16.35 0.11 Average transition A Live crovn base height 14 2.16 3.658 8.90 -4.36 Average transition A Average crovn height 14 -2.21 3.971 -9.96 5.17 Average transition B Live crovn base height 14 -3.12 3.737 -10.88 3.04 Average transition B Average crovn height 14 -7.50 4.993 -17.94 -1.52 110 T a b l e 19. C o r r e l a t i o n n a t r i x f o r l i v e c r o v n base h e i g h t , average c r o v n h e i g h t , a v e r a g e t r a n s i t i o n h e i g h t A and a v e r a g e t r a n s i t i o n h e i g h t B. ! L i v e Crovn ! Average ! Average ! Average ! Base H e i g h t ! Crovn H e i g h t ! T r a n s i t i o n • T r a n s i t i o n I 1 ! H e i g h t A 1 H e i g h t B L i v e C r o v n Base H e i g h t 1.0000 Average Crovn H e i g h t 0.8402 It 1.0000 Average T r a n s i t i o n H e i g h t A 0.8419 II 0.7936 II 1.0000 Average T r a n s i t i o n H e i g h t B 0.7340 t l 0.5888 1 0.7407 II 1.0000 I S i g n i f i c a n t a t t h e 0.05 l e v e l II S i g n i f i c a n t a t t h e 0.01 l e v e l (14 o b s e r v a t i o n s ) I l l Figure 1. Location of Douglas-fir stands. 112 o.e f i i i i i i ; i i i i 5 10 IS 20 25 SO 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Figure 2. Pith to bark relative density profiles for sanple tree IAS. 113 1MEIGMT»B.H7| -1 1 : 1 1 1 1 I 1 1 1— 5 10 15 20 25 30 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Figure 3a. Segmented linear regression aodel or. pith to bark r e l a t i v e density p r o f i l e for a sample radius. Figure 3b. Simple linear regression model on pith to bark r e l a t i v e density p r o f i l e for a saaple radius. • t • I t 4? < 0 t t t 1 M I t H I 1J I K JO l i t > t t M l i t » ' I t t t t i t s T t t l > X ' K X x y y x x X X WOOOOOt 10 » 10 i t to t t «o « t to t t t o GROWTH NCREMENTS f ROM PITH i n i t >o n i o t t to <t to t t to GROWTH INCREMENTS f ROM PITH K> It 10 » 10 I t >0 4 t 10 I t 10 GROWTH INCREMENTS f ROM PITH F i g u r e 4a. S c a t t e r p l o t o f h e i g h t over nunber o f growth i n c r e m e n t s at which j u v e n i l e - n a t u r e wood t r a n s i t i o n o c c u r s . F i g u r e 4b. S c a t t e r p l o t o f h e i g h t over nunber o f growth i n c r e n e n t s at the b a s e of dead b r a n c h e s f o r a l l t r e e s . F i g u r e 4c. S c a t t e r p l o t o f h e i g h t o v e r nunber o f growth i n c r e n e n t s which i n d i c a t e s t h e l o w e s t r e l a t i v e d e n s i t y v a l u e i n t h e p r o f i l e . 4 7 . 5 - 4 5 - 4 2 . 5 - 4 0 - 37.5 35 3 2 . 5 - 3 0 - 2 7 . 5 - X 2 5 -o UJ 2 2 . 5 - I 2 0 - 17.5- 15- 12.5- 10 - 7 .5 - 5 - 2 . 5 - 0 y • -0.1313 «• 0 .5833 X r • 0 .8894 .8' 9' • D • 12.5 15 17.5 20 22.5 75 27.5 30 32.5 35 37.5 40 42.5 45 47.5 TOTAL HfTGHT (m) Figure 3*. Scatter plot and height prediction aodel for crovn base height over total height. Figure 3b. Scatter plot and height prediction aodel for average crovn height over total height. 116 47.5- : i i 1 1 1 1 1 1 1 ! : 1 1 1— 12.5 15 17.5 20 22.5 25 27.5 30 32.5 35 37.5 40 42.5 45 47.5 TOTAL HEIGHT (m) F i g u r e 6. S c a t t e r p l o t o f a) t o t a l h e i g h t and h e i g h t p r e d i c t i o n t o d e l s o ver t o t a l h e i g h t ; f o r : b) a v e r a g e crown h e i g h t ; and c ) crown base h e i g h t . 117 4i s- i i i ' i , 1 i i 1 i i \ .* , 0 5 » 15 30 71 JO ii 40 45 50 55 GROWTH INCREMENTS FROM PITH Figure 7. Graphical representation of: a) total tree height; and b) crovn base height over nunber of growth increnents fron the pith at breast height. 118 4J.S- GROWTH INCREMENTS FROM PITH Figure 8. Graphical representation of: a) total tree height; b) crovn base height before harvest; c) l i v e crovn base height at harvest; and d) average crovn height at harvest over nuaber of growth increaents froa the pith at breast height. Figure Sa. Scatter and height prediction nodel for total tree height over nunber of growth increments f r o i the pith at breast height. V = -3.5855 + 0.9854x - 0.0037x r = 0.9324 x x X X X . xy/y. ,'X x X / x »- X XX? XXX 10 It 70 25 SO SB 40 45 50 B5 60 GROWTH INCREMENTS FROM PITH Figure 9b. Scatter and height prediction nodel for lowest r e l a t i v e density over nuiber of growth increnents fron the pith at breast height. 2 y = -6.3482 + 1.0073x - O .OO88X r = 0.9089 40 6 39- 37.5- 38 34.5- 33- 31.6- 30- 28 6- 27- ? 26.5 J ' • I ' l 1 i I 1 i i i i 0 6 10 16 20 25 30 35 40 46 60 65 60 GROWTH INCREMENTS FROM PITH 46- 43 5 42 Figure 10a. Scatter and height prediction nodel for height to crown base over nunber of growth increments f r o i the pith at breast height. 46 43 6 42 40 6 39 376 36 34 6 33 316 30 26 6 27 "E 266 t— 24 5 22 8 UJ X 2' 166 18 16 5 16 13 6 12 10 5 H 9 7.6 6 4.6 6.9988 + 0.4853X • 0.7 174 B B B B H B B p / / / / / / / / / / B J» »»*B BEE B BB 10 16 20 26 SO 36 40 46 60 65 80 GROWTH INCREMENTS FROM PITH Figure 10b. Scatter and height prediction nodel for juvenile - nature wood transition points over nunber of growth increments fron the pith at breast height. 121 1 i 11 - i — 1 — i 1 1 •! - i 'l 11 r——r- 0 5 10 15 20 25 30 35 40 45 60 65 60 GROWTH INCREMENTS FROM PITH Figure 11. Height prediction nodels for: a) total tree height; b) lowest relative density height; c) crovn base height; d) juvenile - nature wood transition height over nunber of growth increnents fron the pith at breast height; and e) diagranatic tree representations. u z I o ie- y = 11.0912 - 0 4264x o r = -0.5646 16- o 14 - o 0 12- o o_ 10- o'~'-~- o o o o 8 o o *• * « ~ « ^ O 6- § ° 0 O 4 - o 2- Q n -2- -4- O C 8 10 12 14 TRANSITION HEIGHT H Figure 12a. Scatter and height prediction aodel for the difference between crovn base height and juvenile - nature vood transition height over juvenile - nature vood transition height. 28- 26 24- 22- 20 18- 16- 14 - 12- 10- 8- 6- 4 - 2- o o o 8 o 8 o y = 19.3270 - 0.2319x r = -0.2319 8 o o o <9 S 8 10 12 14 TRANSITION HEIGHT M —t— 16 Figure 12b. Scatter and height prediction aodel for the difference betveen total height and juvenile - nature vood transition height over juvenile - nature vood transition height. 123 Figure 13. Graphical representation of: a) estimation of the average transition height A; and b) estination of the average transition height height 8 over nunber of growth increnents froa pith at breast height. 124 41 46- 44 42- 40- 16- 16 14 c E S » H so .E .e *» E " U « < " * 14 12 H 10 • e 4- I 0 V \ * - >A — • r«> \ / \ / o —r— B.H — r ~ 20%. T Legend A TREC-U5 X mt-u? • TR£[_-166 E TREE —1E11 E TREE-1C1 ¥ 1REJ^IC6 4- IfCE-IM & 1RCE-1D6 o Ifrr^iES, 4 TREC-1C6 O T«£-ir7 E TREE-iriO V 1REE-CR1 E 1BIC-CR? 40% AVG TRANS ( A ) TREE SECTION Figure 14. Scatter plot of juvenile - nature (J. N.) wood transition nuiber of growth increments over tree sections and overall section averages, i . e . average t r a n s i t i o n age A. 125 z UJ g LU X z o IS) Z < o 46 43 6- 42- 40 6- 3* 37.5 se 34 5 33 315 30 235 27 26 6 24 22.6 21 18 6- 18- 16 6- 15 13 6- 12- 106 • 76 e 4 6 * o •-r, Leoend TRCt - 1 * 5 X met -U7 D 1BCC -»6 E iRtr -ten E m t - I C 1R£E -1C6 * If" e -106 0 IRCt •t -ue o m r - V 7 c 1REE -irio V 1 « £ -C»l E l « t - C K 2 — r - B.H. 20% TREE SECTION —I 1 40% AVG TRANS (B) Figure IS. Scatter plot of height differences atong total and transition heights over tree sections and overall section averages, i . e . average transition height B. 47.5 45- 42.3- 40- 37.3- 35 32 5- 30- (m ) 27.5- y- X 25- O U 22.5- I 20 17 5- 15 12.5- 10- 7.5- 5- 2.S- 0- y = -5.1764 + 0.7894 X r = 0.8248 B B / a / / ^ B3 s B 1 I I I I 1 I I I I I ! I I I I2.S IS 17.5 20 22.5 23 27.5 30 32 3 33 37.5 40 42 3 43 47.5 TOTAL HEIGHT (m) Figure 16a. Scatter plot and height prediction nodel for average transition height A over total height. 47.5- 45- 42 5 40- 37.3 33- 32.3- 30- (m ) 27.5- 23-X o UJ 22 5-X 20- 17.5- 15 12.5- 10- 7.5- 5- 2.5- 0 \- y = -5.2892 + 0.6421 X r = 0.7811 r o x*.>* 17 5 15 17 5 20 22.5 25 27.5 30 32 5 33 37.3 40 42.3 43 47 5 TOTAL HEIGHT (m) Figure 16b. Scatter plot and height prediction nodel for average t r a n s i t i o n height B over total height. 127 Figure 17. Scatter plot of a) total tree height, and height prediction aodels over total height for: b) average crovn height; c) average transition height A; d) live crovn base height; and e) average transition height B. 128 GROWTH INCREMENTS FROM PITH Figure 19. Pith to hart relative density profiles for pruned tree RF3. 129 Figure 18. Pith to bark relative density profiles for pruned tree Rf2. 130 Appendix 1. Average Crown Height E s t i m a t i o n Procedure 1. The length o f each branch (BL) was p l o t t e d a g a i n s t the v e r t i c a l d i s t a n c e from the t e r m i n a l leader t o the base o f the branch (L) t o observe the a c t u a l shape o f each sampled crown (Appendix l a ) . 2. The length o f each branch (BL) was p l o t t e d a g a i n s t t h e transformed v e r t i c a l d i s t a n c e from the t e r m i n a l leader t o the base o f the branch (Appendix l b ) : l n [ ( L/c ) + 1 ] where: ln = n a t u r a l l o g a r i t h m L = d i s t a n c e from the t e r m i n a l leader t o the branch base or crown 1ength c = c o e f f i c i e n t t h a t d e s c r i b e s the c u r v a t u r e o f the crown p r o f i l e (estimated f o r D o u g l a s - f i r as 6.1 by M i t c h e l l (1975)) 131 The s l o p e o f each crown, or r e g r e s s i o n c o e f f i c i e n t (b) v a l u e s t h a t r e l a t e branch growth t o he i g h t growth were estimated u s i n g the f o l l o w i n g r e g r e s s i o n equat i on: BL = bd [ In ( L/c ) + 1 ] (1) where: BL = branch length b = r e g r e s s i o n c o e f f i c i e n t t h a t r e l a t e s branch growth t o h e i g h t growth d = c o e f f i c i e n t t h a t compensates f o r branch crooks (estimated f o r D o u g l a s - f i r as 0.975, by Mitchel1 (1975)) The average crown r a d i u s , which r e p r e s e n t e d the maximum branch length (BL), was u t i l i z e d t o estimate t h e d i s t a n c e from the t e r m i n a l leader t o the crown base u s i n g Equation 1 and s o l v i n g f o r L (Appendix l c ) as fol1ows: L = c ( e B L / ( b d ) - 1 ) where: e = 2.71828 Average crown he i g h t was c a l c u l a t e d by s u b t r a c t i n g L from the t o t a l t r e e h e i g h t (Table 3 ) . 132 • i i i i ' i i i I 0 1.5 3 4.5 6 7.5 9 10.5 12 13.5 VERTICAL DISTANCE FROM THE LEADER (L) (m) Appendix l a . R e l a t i o n s h i p between t o t a l b r a n c h l e n g t h (BL) and t h e v e r t i c a l d i s t a n c e f r o i t h e l e a d e r (L) f o r S a t p l e T r e e 1A5. 133 4.5 3.5- X o z X u z < cr m 2.5- 0.5 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 VERTICAL DISTANCE FROM THE LEADER ln[(L/c)+l)] Appendix l b . R e l a t i o n s h i p between t o t a l b r a n c h l e n g t h (BL) and t h e t r a n s f o r a e d v e r t i c a l d i s t a n c e f r o i t h e l e a d e r l n [ ( L / c H l ] f o r S a i p l e T r e e 1A5 . 134 - A: CROWN RADIUS J Q' o/ O / 4 7 - 0 o / 0 0 w 0 / 0 4 - 0 4 - 0 4 /o / 0 c 0 0 0 .6 0 0 0 0 4 0 t 0 0 U - — i — - i 1 1 -4 B: AVERAGE CROWN POSITION 0-2 0.4 0.6 0.6 B l 1.2 1.4 1.6 VERTICAL DISTANCE FROM THE LEADER ln[(L/c)+l)] Appendix l c . Average crown h e i g h t p o s i t i o n d e t e r m i n a t i o n f o r s a a p l e t r e e 1A5. 135 BRANCH Y E A R S Appendix 2. R e l a t i o n s h i p between t o t a l h e i g h t and b r a n c h age t o e s t i m a t e base of l i v e crown p o s i t i o n s at young a g e s . 136 Appendix 3. Summary o f X-Ray D e n s i t o m e t r i c A n a l y s i s Procedure 1. A f t e r a i r d r y i n g , the wood sample s t r i p s were mounted and glued between two mounting s t i c k s . 2. The mounted samples were reduced t o a uniform t h i c k n e s s o f two mm u s i n g a s p e c i a l l y designed twin blade c i r c u l a r saw. 3. I d e n t i f i c a t i o n c h a r a c t e r s were then w r i t t e n on the mounts ad j a c e n t t o the wood samples u s i n g an x-ray opaque lead based p a i n t . 4. The wood samples were e x t r a c t e d by immersion i n a s o l u t i o n o f 1:2 a l c o h o l benzene f o r 30 minutes and then a i r d r i e d a t room temperature. 5. A p o r t i o n o f the core mounting s t i c k was removed t o measure the angle between the l o n g i t u d i n a l t r a c h e i d s and the long a x i s o f the sample s u r f a c e . T h i s angle was measured with a goniometer i n the eyepiece o f a low power s t e r e o s c o p i c microscope. 6. The wood samples a l o n g with c a l i b r a t i o n wedges were p l a c e d on f i n e g r a i n e d , high r e s o l u t i o n , s i n g l e emulsion x-ray f i l m s . The c a l i b r a t i o n wedges, made o f D o u g l a s - f i r wood b l o c k s o f known r e l a t i v e d e n s i t y , were u t i l i z e d i n the c o n v e r s i o n o f f i l m d e n s i t y i n t o wood r e l a t i v e d e n s i t y d a t a . 137 7. Radiographs were then made by exposing the wood samples, c a l i b r a t i o n wedges and x-ray f i l m s on a moving c o l 1imated x-ray scanning machine o r i e n t e d a c c o r d i n g t o the angle o f the l o n g i t u d i n a l t r a c h e i d s . 8. The radiographs were developed i n s p e c i a l l y designed f i l m p r o c e s s i n g tanks c o n t a i n i n g separate s o l u t i o n s o f d e v e l o p er, stop bath i n d i c a t o r and f i x e r with hardener. The tanks were p l a c e d i n a temperature c o n t r o l l e d w a t e r j a c k e t . The length o f time and temperature a t which the radiographs were exposed t o the chemicals was determined a c c o r d i n g t o the chemical manufacturer's i n s t r u c t i o n s . 9. The developed radiographs were examined on a l i g h t t a b l e under a low power s t e r e o s c o p i c microscope. The p i t h date and the c o r r e s p o n d i n g growth increment c a l e n d a r years were marked, i n decades, on the f i l m s . 10. The radiographs were p l a c e d on a computerized scanning densitometer t h a t converted the wood sample image on the f i l m i n t o growth increment width and r e l a t i v e d e n s i t y data, measured a t 0.01 mm and 0.05 mm s t e p s a l o n g the r a d i u s o f the wood sample, r e s p e c t i v e l y . 11. The data o b t a i n e d from the densitometer were s t o r e d on magnetic tapes f o r f u r t h e r p r o c e s s i n g and summarizing. F o r i n t e k Canada C o r p o r a t i o n ' s data a c q u i s i t i o n Tree Ring Input Program (TRIP) was used t o o b t a i n the average r e l a t i v e d e n s i t y o f each growth i ncrement. 138 Appendix 4. Fortran prograi t o deternine residual sua o f •quarts using non - l inear optimization routines for segnented regression models. L i s t m g of FAST 1 $R • F T N SCARDS'DAVID S S P R 1 N T - - C 2 R -LOAD*NA:NLMON 3 ASSIGN 1-1A53RD<8) 4 CALL GETDAT 5 IN P 6 . 4 1 0 2 5 . . 3 5 6 4 7 E - 2 . 2 0 . .4924 1E-2 7 PR F B EX SIMPLX 9 1 10 2 0 0 . 1 0 11 I E - 0 5 12 EX FNMIN 13 200 14 1 0 . 1 . E - 1 1 16 STOP 17 SET COST-ON L i s t i n g of . . . • D A V I D . S 1 FUNCTION XDFUNC(X.N) 2 IMPLICIT R E A L ' S ! A - H . O - Z ) 3 COMMON / S H A R E / P O I N T S ( 2 . 100).NDAT 4 R E A L ' S XfN) 5 X D F U N C ' 0 . 0 6 DO 100 I -1 .NDAT 7 I F ( P O I N T S ( 1 . 1 ) GT X (3 ) ) X O F U N C « X D F U N C + ( P O I N T S ! 2 . I ) - B 1 ( X ! 1 ) + X ( 2 ) ' X ( 3 ) * X ( 4 ) ' ( P 0 I N T S ( 1 . I ) - X ! 3 ) ) ) ) " 2 9 I F ( P O I N T S ( 1 , l ) . L E . X ( 3 ) ) X D F U N C " X D F U N C * ( P O I N T S ! 2 , I ) - 10 1 < X ( 1 ) * X ( 2 ) ' P 0 I N T S ( 1 . I ) ) ) " 2 11 100 CONTINUE 12 RETURN 13 END 14 C 15 C 16 C 17 SUBROUTINE GETDAT 18 IMPLICIT R E A L ' S ! A - H . O - Z ) 19 COMMON / S H A R E / P 0 I N T S ( 2 . 1 0 0 ) . N D A T 20 DO 100 1 - 1 . 1 0 0 21 R E A D ( 1 . 2 O O . E N D » 5 O O ) P 0 I N T S ( 1 . I ) . P O I N T S ! 2 . I ) 22 20O F O R M A T ( T 6 . F 2 . 0 . F 1 1 . 7 ) 23 W R I T E ( 6 . 2 O O ) P 0 I N T S ( 1 . I ) . P O I N T S ( 2 . I ) 24 NDAT-I 25 100 CONTINUE 26 500 RETURN 27 END 1 |HEIGHT-803? HEIGHT-60% 0 6- 0 6 - 0 4 - lHEIGHT-40%1 0 6 0 6- 0.4 1 I 1 1 i 1 I 1 I 1 I - 5 10 15 20 25 30 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix S. a) Tree IAS. Simple and segaented linear regression models on pith to bark relative density profiles. Legend A HT/C. INCREMENTS TROM PITH X HT/LOWEST RELATIVE DENSITY • HT/CROWN BASE EJ HT/J. - M. WOOD TRANSITION _ I i I 1 I I 1 1 I 1 I I . ' 0 6 10 16 20 25 30 35 40 46 60 66 60 GROWTH INCREMENTS FROM PITH Appendix 5. b) Tree IAS. Relationships between total tree height, lowest relative density height, crown base height and juvenile - mature wood transition over nuaber of growth increments from pith at breast height. 1 1 1 1 1 1 i 1 1 1 r 5 10 15 20 25 30 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix f>. a) Tree 1A7. Siapie and segaented linear regression aodels on pith to bark relative density profiles. Legend A HT/G. INCREMENTS FROM PITH X HT/LOWEST RELATIVE DENSITY • HT/CROWN BASE H HT/J - M. WOOD TRANSITION -1 1 I 1 1 I 1 1 1 1 I 1 — 1 0 5 10 15 20 25 30 35 40 45 60 65 60 GROWTH INCREMENTS FROM PITH Appendix f>. b) Tree 1A7. Relationships between total tree height, lowest relative density height, crown base height and juvenile - nature wood transition over nuaber of growth increaents froa pith at breast height. 10 15 ?0 75 Jf 35 40 «5 50 Si GROWTH INCREMENTS FROM PITH Appendix 7. a) Tree IBS. Sinple and segnented linear regression nodels on pith to bark relative density p r o f i l e s . i i { i i i 1 1 i 1 1 1 i i 0 6 10 16 20 25 30 36 40 46 60 65 60 GROWTH INCREMENTS FROM PITH Appendix 7. b) Tree 1B6. Relationships between total tree height, lowest r e l a t i v e density height, crown base height and juvenile - nature wood transition over nunber of growth increnents fron pith at breast height. 0.6 0 5 ^ 0.4 0 .6- 0.5 0 4 tn 0.6 z 0.5 0 4- 0 6 0 6 0 4 0.6 0 6-1 0.4 lHEIGMT-,B0%j [HEJGHT-60*J |HEIGHT-20% HEIGHT-B.H. 5 10 15 70 ?5 ?0 J5 40 45 50 55 60 GROWTH INCREMENTS FROM PITH Appendix 8. a) Tree 1BU. Siaple and segaented linear regression aodels on pith to bark relative density profiles. 46 4 3 5 42 40.6 39 37.6 36 - 34 6 33 31.5 3 0 - 28 6 27- 25 6- 24 Legend A HT/G. INCREMENTS FROM PITH X HT/LOWEST RELATIVE DENSITY • HT/CROWN BASE HT/J. - M. WOOD TRANSITION_ •P- N3 15 20 25 30 35 40 45 50 GROWTH INCREMENTS FROM PITH Appendix 8. b) Tree IBM. Relationships between total tree height, lowest relative density height, crown base height and juvenile - nature wood transition over nunber of growth increments froa pith at breast h*ight. 0.6- 0 5- 04 0 6 0 5 04 06 06 1 0 4 06 06 0-4 H 0 6-t 06 04 [HEIGHT-8 0*| [HEIGHT-60%] |HEIGHT-40%J |HEIGHT-20lt] |HEIGHT-B.H"] — i . i I I I I I I I I — 5 10 15 20 25 JO 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix 9. a) Tree 1C1. Sinple and segnented linear regression nodels on pith to bark relative density profiles. 46- 43 6- 42- 40.6- 39- 37.6- 36- 34 6 - 33- 316- 30- 28 6- 27- (m ) 26.5- r— 24- X 22 5-o U J 21- 19.5- 18- 16.6- 15- 13.6- 12- 10.6 9 - 7.6- 6- 4.6- 3- 1.6 A Legend A HT/G. INCREMENTS TRQM PITH X HT/LOWEST RELATIVE DENSITY • HT/CROWN BASE HT/J.- M. WOOD TRANSITION —T— 10 T I 1 1 1 1— 20 25 30 35 4 0 46 50 GROWTH INCREMENTS FROM PITH - 1 — 15 55 6 0 Appendix 9. b) Tree 1C1. Relationships between total tree height, lowest relative density height, crown base height and juvenile - nature wood transition over nunber of growth increnents fron pith at breast height. I I i 1 I r 10 15 70 75 ™ J 5 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix 10. a) Tree 1C6. Siaple and segaented linear regression models on pith to bark relative density profiles. 45- 43 5 42 40.5 30 37.5- 36 34.6- 33- 31.6- 30- 28 5- 27- 25.6 24 22 5 2 H 19.6 18 16.6- 15 13 6- 12 10.5 9 7.5 6 4.6 3 1-8 A Legend A HT/G. INCREMENTS FROM PITH X HT/LOWEST RELATIVE DENSITY • HT/CROWN BASE 0 y_TZLli*- WOOD TRANSITION - r i i 1 i 1 i 1 i I 10 15 20 25 30 35 40 45 60 55 60 GROWTH INCREMENTS FROM PITH Appendix 10. b) Tree ICS. Relationships between total tree height, lovest relative density height, crovn base height and juvenile - nature vood transition over nuaber of growth increments froa pith at breast height. 0.6 OS 0 4 0.4- ••• ••• [ H E I G H J - 8 0 » ) I H E I G H T - B . ' H T I 5 10 15 2n 75 30 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix 11. a) Tree IDS. Sinple and segnented linear regression nodels on pith to bark relative density profiles. Legend A HT/G. INCREMENTS FROM PITH X HT/L0WE5T RELATIVE OENSITY • HT/CROWN BASE HT/J . - M. WOOD TRANSITION 1— 15 20 25 30 35 40 GROWTH INCRFMENTS FROM PITH 46 -I— 60 -r— 65 — r - 60 Appendix II. b) Tree IDS. Relationships between total tree height, lowest relative density height, crown base height and juvenile - nature wood transition over nunber of growth increnents fron pith at breast height. H E I G H T - 8 0 % , [ H E J G H T - 6 0 % ; H E I G H T - 4 0 % H E I G H T - 2 0 % | H E I G H T - B R 1 1 1 i 1 : 1 1 — 1 1 1— 5 10 15 70 75 JO J 5 <n A* 50 55 GROWTH INCREMENTS FROM PITH Appendix 12. a) Tree 1D6. Staple and segaented linear regression aodels on pith to bark relativt density profiles. Legend A HT/G. INCREMENTS FROM PITH X HI/LOWEST RELATIVE DENSITY • HT/CROWN BASE B HT/J. - M. WOOD TRANSITION / »A X J , ' S I -1— 15 7 0 2 5 3 0 35 4 0 45 6 0 GROWTH INCREMENTS FROM PITH Appendix 12. b) Tree ID6. Relationships between total tree height, lowest relative density height, crown base height and juvenile - aature wood transition over nunber of growth increments froa pith at breast height. — i — 4 0 1 0 6 5 6 0 06 05 0 4 0.6 0.6 0 4 >-*- in 0 6 z UJ ui 0.6 5 04 ui EE 06 06 0 4 0.6-1 0 6 0.4- V HEIGHT-80% |HEtGHT-40tt| |HEIGHT-20%| |HEIGHT-B"H"1 4n sn 55 GROWTH INCREMENTS FROM PITH Appendix 13. a) Tree 1E3. Sinple and segnented linear regression nodels on pith to bark relative density profiles. 15 20 25 30 35 40 45 60 GROWTH INCRFMENTS FROM PITH Appendix 13. b) Tree 1E3. Relationships between total tree height, lowest r e l a t i v e density height, crown base height and juvenile - nature wood transition over nunber of growth increnents fron pith at breast height. i i 1 '• i I 1 I 1 1 5 10 15 70 25 30 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix 14. a) Tree 1E8. Simple and segaented linear regression aodels on pith to bark relative density profiles. Legend A HT/C. INCREMENTS FROM PITH X HT/LQWEST RELATIVE DENSITY • HT/CROWN BASE B HT/J.- M. WOOD TRANSITION GROWTH INCREMENTS FROM PITH lix 14. b) Tree IE8. Relationships between total tree height, lowest relative density height, crovn base height and juvenile - aature vood transition over nunber of growth increments froa pith at breast height. 0 6 - 0 5 0 . 4 - 0 . 6 - 0 5 0 4 V) 0 . 6 ui OS l 0 . 4 UJ K 0 6 0 . 6 0 . 4 0 6 0 6 0 . 4 A- [ H E I G H T - 8 0 % ! I ^ E I G H T - 6 0 % J I H E I G H T - 4 0 % ) H E I G H T - 2 0 % |HEIGHT-BH1 5 10 15 70 75 J O 3 5 4 0 45 5 0 55 GROWTH INCREMENTS FROM PITH Appendix IS. a) Tree 1F7. Sinple and segnented linear regression nodels on pith to bark relative density profiles. 1 I I 1 I 1 0 1 5 2 0 2 6 3 0 3 5 4 0 4 5 5 0 5 5 6 0 GROWTH INCREMENTS FROM PITH Appendix 15. b) Tree 1F7. Relationships between total tree height, lowest relative density height, crown base height and juvenile - nature wood transition over nunber of growth increnents fron pith at breast height. 0 6 0.5- 0 4- 0 6- 0 5 0 4 ui 0.6 z 0.5 1 0.4 0 6 0.6 0.4 0.6- 0 6 0.4 H [HEIGHT-80%J |HEIGHT-40»1 |HEIGHT-20%| |HEIGHT-B.H~1 5 10 t!> 70 75 30 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix 16. a) Tree 1F10. Siaple and segaented linear regression aodels on pith to bark relative density p r o f i l e s . 45- 43.6- 42- 40.6- 38- 37.6- I I I i I i 1 1 1 i l l 1 0 6 10 15 20 25 30 35 4 0 45 SO 65 60 GROWTH INCREMENTS FROM PITH Appendix 16. b) Tree IF10. Relationships between total tree height, lowest r e l a t i v e density height, crown base height and juvenile - nature wood transition over nunber of growth increments froa pith at breast height. Legend A HT/G. INCREMENTS FROM PITH X HT/LOWEST RELATIVE DENSITY • HT/CROWN BASE G3 HT/J.- M. WOOD TRANSITION -- [HEIGHT-80%| <fv. |HEIGHT-40%] 1 HEIGHT-20% 1 1 1 i 1 1 i 1 [HEIGHT-B.HJ GROWTH INCREMENTS FROM PITH Appendix 17. a) Tret CR1. Sinple and segnented linear regression nodels on pith to bark relative density profiles. Legend A HT/G, INCREMENTS FROM PITH X HT/LOWEST RELATIVE DENSITY B HT/J.- M. WOOD TRANSITION I i i 1 i 1 : 1 1 i 1 1 1 • 0 6 10 15 20 25 30 35 40 45 60 65 60 GROWTH INCREMENTS FROM PITH Appendix 17. b) Tree CRI. Relationships between total tree height, lowest relative density height, crown base height and juvenile - nature wood transition over nunber of growth increnents fron pith at breast height. 5 m 15 20 25 JO J5 40 4b 50 55 GROWTH INCREMENTS FROM PITH Appendix 18. a) Tree CR2. Sinple and segmented linear regression aodels on pith to bark relative density profiles. Legend A HT/G. INCREMENTS FROM PITH X HT/LOWEST RELATIVE DENSITY H HT/J.- M. WOOD TRANSITION 1 I 1 I I I 1 1 1 1 1 1 0 6 10 15 20 25 30 35 40 45 50 65 60 GROWTH INCREMENTS FROM PITH Appendix 18. b) Tree CR2. Relationships between total tree height, lowest relative density height, crown base height and juvenile - nature wood transition over nuaber of growth increnents froa pith at breast height. 0.6 |HEIGHT-80%| |HEIGHT-60%| HEIGHT-40%| \ A : . . . . HEIGHT-20%| • • ! • HEIGHT-B H.| 1 1 I 1 1 1 1 1 I 1 r- 5 10 15 20 25 SO 35 40 45 50 55 GROWTH INCREMENTS FROM PITH Appendix 19. a) Tree RFt. Sinple and segaented linear regression aodels on pith to bark relative density profiles. 46 43.5 42 40.6 39 37.6 36 34.6 33 31.5 30 286 27 25.5 24- 22.6 21 19.6 18- 16 5 16 13 6 12- 10.6 9- 7.6 8 4.6 3 1-6 A Legend A HT/G. INCREMENTS FROM PITH X HT/LOWEST RELATIVE DENSITY • HT/CROWN BASE HEIGHT 10 16 20 25 30 36 40 45 50 GROWTH INCREMENTS FROM PITH —i i— 65 60 Appendix 19. b) Tree RF1. Relationships between total tree height, lowest relative density height and crown base height over mincer of growth increments froa pith at breast height. 154 Appendix 20. Sunnary of relative density data. a) Tree IAS Height Oianeter Section Nunber of 6rovth Relative Density (n) (cn) Height Increnents I.B. O.B. Juv. Hat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 46.8 40.3 B.H. 22 34 56 .486 .058 .620 .380 .572 .044 .640 .480 .542 .062 .640 .380 7.5S 39.3 33.8 201 28 19 47 .438 .054 .570 .360 .513 .044 .620 .420 .468 .063 .620 .360 14.90 34.1 29.5 40X 25 15 40 .422 .043 .540 .370 .483 .033 .520 .400 .445 .049 .540 .370 22.20 27.0 25.9 601 28 - 28 .460 .038 .560 .400 - - - - .460 .038 .560 .400 29.40 19.5 18.7 BOX 13 - 13 .440 .030 .510 .410 - - - - .440 .030 .510 .410 b) Tree 1A7 Height Dianeter Section Nunber of firovth Relative Density (n) (cn) Height Increnents I.B. O.B. Juv. Nat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 46.1 39.8 B.H. 19 32 51 .525 .052 .620 .430 .597 .040 .660 .460 .569 .057 .660 .430 7.20 41.7 37.3 201 24 20 44 .482 .067 .600 .370 .567 .042 .650 .470 .520 .071 .650 .370 15.10 37.0 32.8 401 24 IS 39 .471 .046 .570 .400 .495 .042 .550 .380 .480 .045 .570 .380 22.50 30.7 26.5 601 31 - 31 .479 . 054 . 670 . 410 - - - - .479 . 054 . 670 . 410 29.90 17.6 16.1 801 18 - IB .499 . 038 . 600 . 450 - - - - .499 . 038 . 600 . 450 155 Appendix 20. Suaaary of relative density data (cont.l. c) Tree 116 Height Diameter Section Number of Growth Relative Density (m) (cm) Height Increments l.B. O.B. Juv. Hat. Total Juvenile Hood nature Mood Total Hood Wood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 49.2 40.0 B.H. 16 37 S3 .467 .035 .560 .420 .551 .042 .650 .450 .520 .055 .650 .420 8.SS 39.S 36.S 201 17 28 45 .448 .038 .S60 .400 .539 .030 .590 .490 .504 .OSS .590 .400 17.20 33.5 31.5 401 18 14 32 .470 .034 .540 .420 .526 .027 .570 .490 .495 .042 .570 .420 25.80 25.6 24.5 601 24 - 24 .478 .027 .540 .440 - - - - .478 .027 .540 .440 36.10 14.5 13.3 802 12 - 12 .479 .052 .610 .420 - - - - .479 .052 .610 .420 d) Tree 1B11 Height Diameter Section Number of Growth Relative Density (m) (ca) Height Increments l .B. O.B. Juv. Hat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 49.1 43.5 B.H. 32 25 63 .515 .044 .610 .430 .572 .041 .680 .510 .543 .057 .680 .430 7.10 41.8 37.7 201 25 28 53 . 480 . 039 . 570 . 410 . 4% .034 .590 .440 .489 .037 .590 .410 14.20 36.5 32.0 401 16 29 45 .479 .032 .530 .410 .477 .034 .580 .430 .478 .033 .580 .410 21.30 27.7 24.7 601 29 - 29 .479 .031 .560 .430 - - - - .479 .031 .560 .430 28.45 15.8 14.0 80Z 19 - 19 .488 .032 .570 .450 - - - - .488 .032 .570 .450 156 Appendix 20. Sunnary of relative density data (cont.). e) Tree IC1 Height Dianeter Section Nunber of Growth Relative tensity (n) (cn) Height Increnents I.B. O.B. Juv. Nat. Total Juvenile Hood Hature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 47.3 40.7 B.H. 19 35 54 .503 .037 .590 .440 .586 .035 .660 .490 .558 .053 .660 .440 8.00 40.1 36.2 201 25 22 47 . 464 .043 . 560 . 390 . 530 . 027 . 570 . 470 . 490 . 049 . 570 . 390 16.00 36.1 32.9 401 29 10 39 .458 .030 .520 .400 .497 .019 .520 .450 .468 .032 .520 .400 24.15 29.8 25.9 601 29 - 29 .448 .023 .510 .410 - - - - .448 .023 .510 .410 32.00 12.0 14.9 80Z 15 - 15 .411 .015 .460 .400 . . . . .411 .015 .460 .400 f) Tree 1C6 Height Dianeter Section Nunber of firovth Relative tensity (n) (ci) Height Increnents I.B. O.B. Juv. Hat. Total Juvenile Hood Hature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 47.1 37.5 B.H. 15 38 S3 .502 .052 .650 .440 .592 .046 .700 .500 .566 .062 .700 .440 7.60 39.8 34.2 201 35 11 46 .489 .059 .580 .380 .544 .032 .600 .510 .502 .059 .600 .380 15.20 35.1 31.5 402 26 10 36 .488 .043 .560 .430 .518 .019 .560 .500 .496 .040 .560 .430 22.80 29.0 26.7 601 25 - 25 .478 .034 .550 .410 - - - - .478 .034 .550 .410 30.40 14.4 13.2 801 12 - 12 .499 .035 .560 .430 - - - - .499 .035 .560 .430 157 Appendix 20. Sunnary of relative density data (cont.). g) Tree 10S Height <n) Dianeter (cn) I.B. O.B. Section Height Nunber of 6routh Increnents Juv. Hat. Total Hood Hood Sect. Relative Density Juvenile Hood Hean S.D. Hax. Hin. Hature Hood Hean S.D. Hax. Hin. Total Hean S.D. Hax. Hin. 1.30 45.5 26.8 B.H. 13 14 33 .462 .031 .540 .420 .490 .032 .540 .440 .474 .034 .540 .420 6.40 35.7 31.9 201 20 7 27 .466 .026 .500 .430 .530 .032 .560 .480 .482 .039 .560 .430 12.80 27.6 25.9 401 20 - 20 .475 .035 .550 .430 - .475 .035 .550 .430 19.20 20.3 18.2 60Z 14 - 14 .456 .034 .510 .390 - .456 .034 .510 .390 25.60 11.3 10.1 801 8 - 8 .540 .027 .580 .500 - .540 .027 .580 .500 h) Tree 1D6 Height Dianeter Section Nunber of firovth Relative Density (n) (cn) I.B. O.B. Height Increnents Juv. Hat. Total Hood Hood Sect. Juvenile Hood Hean S.D. Hax. Hin. Nature Hood Hean S.D. Hax. Hin. Total Hean S.D. Hax. Hin. 1.30 43.2 38.5 B.H. 17 18 35 .445 .055 .550 .380 .530 .033 .600 .490 .488 .062 .600 .380 5.90 .384 34.3 201 15 14 29 .407 .031 .470 .350 .468 .031 .520 .430 .437 .043 .520 .350 11.90 33.4 32.1 40Z 23 - 23 .450 .037 .550 .400 - .450 .037 .550 .400 17.70 25.8 23.4 601 17 - 17 .428 .041 .530 .360 - .428 .041 .530 .360 23.60 13.2 12.2 801 8 8 .468 .027 .510 .420 _ _ - _ .468 .027 .510 .420 158 Appendix 20. Summary of relative density data (cont.). i) Tree 1E3 Height Diameter Section Number of 6rovth Relative Density (m) (cm) Height Increments l.B. O.B. Juv. Hat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Mean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 39.4 37.6 B.H. 28 15 43 .574 .045 .670 .500 .634 .028 .680 .590 .595 .049 .680 .500 7.10 35.3 32.5 201 26 6 32 .487 .030 .560 .440 .546 .031 .590 .500 .498 .038 .590 .440 14.00 31.3 28.5 401 11 15 26 .444 .034 .510 .390 .454 .013 .480 .430 .450 .024 .510 .390 21.00 22.8 21.1 601 17 - 17 .417 .017 .450 .400 - - - - .417 .017 .450 .400 28.00 12.8 11.4 80Z 9 9 .483 .031 .560 .450 - - - - .483 .031 .560 .450 j) Tree 1E8 Height Diaaeter Section Number of 6rovth Relative Density (a) (ca) Height Increments l.B. O.B. Juv. Hat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 68.2 57.1 B.H. 34 13 47 .472 .042 .590 .390 .527 .016 .570 .510 .487 .044 .590 .390 7.20 54.7 48.6 201 26 IS 41 .441 .057 .610 .360 .503 .026 .570 .460 .463 .057 .610 .360 14.40 45.4 40.5 40Z 33 - 33 .456 .039 .530 .370 - - - - .456 .039 .530 .370 21.60 36.3 32.5 601 25 - 25 .420 .034 .500 .360 - - - - .420 .034 .500 .360 28.80 21.3 19.7 601 14 - 14 .454 .030 .530 .420 - - - - .454 .030 .530 .420 159 Appendix 20. Summary of relative density data (cont.). k) Tree 1F7 Height Dianeter Section Nunber of Growth Relative Density (•) (cn) Height Increments l.B. O.B. Juv. Hat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 S7.S 48.3 B.H. 25 28 53 .503 .053 .650 .430 .595 .025 .640 .550 .551 .061 .650 .430 8.30 47.3 44.0 20Z 25 21 46 .454 .061 .610 .380 .533 .026 .600 .510 .490 .061 .610 .380 16.40 39,9 37.3 401 24 14 38 .470 .043 .570 .420 .478 .033 .550 .430 .473 .040 .570 .420 24.90 30.9 26.8 601 22 - 22 .497 .056 .650 .430 - - - - .497 .056 .650 .430 33.70 16.1 14.7 801 14 - 14 .517 .058 .640 .450 - - - - .517 .058 .640 .450 1) Tree 1F10 Height Diaaeter Section Nuaber of Growth Relative Density (a) (ca) Height Increaents l.B. O.B. Juv. Nat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 52.7 45.3 B.H. 24 28 52 .492 .054 .640 .430 .576 .030 .630 .510 .537 .060 .640 .430 7.80 41.S 36.4 207. 22 24 46 .450 . 048 . 570 . 390 . 517 . 032 . 570 . 450 . 485 . 052 . 570 . 390 15.90 35.0 31.3 401 15 24 39 .446 .028 .490 .410 .487 .021 .530 .440 .472 .030 .530 .410 23.40 28.0 23.9 601 26 - 26 .495 .026 .550 .460 - - - - .495 .026 .550 .460 31.20 16.5 14.4 801 19 - 19 .470 .042 .560 .430 - - - - .420 .042 .560 .430 160 Appendix 20. Sunnary of relative density data (cont.). n) Tree Cfil Height Dianeter Section Nunber of Growth Relative Density (n) (cn) Height Increnents ~ I.B. O.B. Juv. Hat. Total Juvenile Hood Hature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Max. Hin. Hean S.D. Hax. Hin. 1.30 22.1 20.0 B.H. 20 17 37 .491 .054 .610 .410 .590 .046 .670 .520 .536 .070 .670 .410 3.34 19.8 18.4 201 19 15 34 .490 .054 .660 .420 .612 .034 .680 .560 .543 .076 .680 .420 5.10 18.0 16.8 40Z 31 14 31 .486 .069 .620 .390 - .486 .069 .620 .390 9.95 12.3 11.4 601 17 - 17 .485 .025 .540 .450 - .485 .025 .540 .450 13.36 6.3 5.7 801 7 - 7 .485 .040 .540 .430 - .485 .040 .540 .430 n) Tree CR2 Height Dianeter Section Nunber of 6rowth Relative Density (n) (cn) Height Increnents I.B. O.B. Juv. Hat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.40 42.4 38.4 B.H. 23 6.40 36.8 34.5 201 13 11.80 33.6 31.7 401 22 18.72 24.8 23.4 601 20 25.77 10.7 10.0 801 16 12 35 .428 .038 .510 .340 .473 16 29 .443 .037 .500 .370 .514 22 .488 .028 .540 .440 - 20 .459 .048 .630 .400 - 16 .493 .041 .590 .440 - .017 .500 .440 .444 .039 .510 .340 .032 .580 .440 .483 .049 .580 .370 - - - .488 .028 .540 .440 - .459 .048 .630 .400 - - - .493 .041 .590 .440 161 Appendix 20. Suanary of relative density data (cont.). o) Tree RF1 Height Dianeter Section Nunber of Growth Relative Density (a) (ca) Height Increaents l.B. O.B. Juv. Hat. Total Juvenile Hood Nature Hood Total Hood Hood Sect. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. Hean S.D. Hax. Hin. 1.30 28.3 26.0 B.H. 21 - 21 .429 .041 .530 .360 - - - - .429 .041 .530 .360 4.54 24.3 22.3 201 17 - 17 .423 .035 .500 .380 - - - - .423 .035 .500 .380 9.00 20.6 18.6 40Z 13 - 13 .398 .054 .500 .340 - - - - .398 .054 .500 .340 13.65 15.0 14.0 60Z 8 - 8 .445 .042 .510 .400 - - - - .445 .042 .510 .400 18.16 7.4 0.6 B0I 4 - 4 .492 .025 .520 .460 - - - - .492 .025 .520 .460 p) Tree RF2 Height (a) Dianeter (ca) l.B. O.B. Section Height Nuaber of Growth Increaents Juv. Hat. Total Hood Hood Sect. Relative Density Juvenile Hood Hean S.D. Hax. Hin. Nature Hood Hean S.D. Hax. Hin. Total Hean S.D. Hax. Hin. 1.30 59.4 68.3 B.H. 21 30 51 .425 .021 .480 .370 .475 .045 .640 .410 .454 .045 .640 .370 3.80 51.6 61.0 10Z 17 30 47 .427 .028 .490 .380 .489 .050 .620 .430 .466 .053 .620 .380 6.30 50.7 56.0 201 44 - 44 .421 .027 .490 .360 - .421 .027 .490 .360 12.30 44.4 50.3 40Z 37 - 37 .432 .026 .500 .390 - .432 .026 .500 .390 18.90 31.1 34.6 601 26 26 .425 .035 .560 .380 _ .425 .035 .560 .380 162 Appendix 20. Sunnary of relative density data (cont.). q) Tree Rf3 Height (n) Dianeter (cn) I.B. O.B. Section Height Hunber of firovth Increnents Juv. Hat. Total Hood Hood Sect. Relative Density Juvenile Hood Hean S.D. Hax. Hin. Hature Hood Hean S.D. Hax. Hin. Total Hean S.D. Hax. Hin. 1.30 37.5 44.0 B.H. 15 30 45 .482 .035 .600 .440 .523 .023 .580 .490 .509 .033 .600 .440 2.90 34.4 40.5 10Z 13 30 43 .438 .039 .560 .400 .490 .029 .570 .430 .474 .040 .570 .400 4.35 32.0 36.B 20Z 39 39 .458 .036 .580 .380 - .458 .036 .580 .380 11.60 25.0 30.4 401 33 33 .431 .026 .490 .380 - .431 .026 .490 .380 17.75 17.0 19.6 60Z 21 21 .470 .027 .560 .440 _ .470 .027 .560 .440

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