UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Fertilization of stagnated sitka spruce plantations of northern Vancouver Island Germain, André Yvon 1985

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
831-UBC_1985_A6 G47.pdf [ 10.46MB ]
Metadata
JSON: 831-1.0095955.json
JSON-LD: 831-1.0095955-ld.json
RDF/XML (Pretty): 831-1.0095955-rdf.xml
RDF/JSON: 831-1.0095955-rdf.json
Turtle: 831-1.0095955-turtle.txt
N-Triples: 831-1.0095955-rdf-ntriples.txt
Original Record: 831-1.0095955-source.json
Full Text
831-1.0095955-fulltext.txt
Citation
831-1.0095955.ris

Full Text

FERTILIZATION OF STAGNATED SITKA SPRUCE PLANTATIONS ON NORTHERN VANCOUVER ISLAND BY ANDRE YVON GERMAIN M.F., The U n i v e r s i t y of B r i t i s h C o lumbia, 1985 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF FORESTRY i n THE FACULTY OF GRADUATE STUDIES V Faculty of Forestry We a c c e p t t h i s t h e s i s as con f o r m i n g t o the r e q u i r e d s t a n d a r d COLUMBIA 1985 THE UNIVERSITY OF BRITISH September 1985 (c) ^ Andre Yvon Germain, I n p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l m e n t o f t h e r e q u i r e m e n t s f o r an advanced degree a t the U n i v e r s i t y o f B r i t i s h C o l u m b i a , I agree t h a t t h e L i b r a r y s h a l l make i t f r e e l y a v a i l a b l e f o r r e f e r e n c e and s t u d y . I f u r t h e r agree t h a t p e r m i s s i o n f o r e x t e n s i v e c o p y i n g o f t h i s t h e s i s f o r s c h o l a r l y purposes may be g r a n t e d by t h e head o f my department o r by h i s o r h e r r e p r e s e n t a t i v e s . I t i s u n d e r s t o o d t h a t c o p y i n g o r p u b l i c a t i o n o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l n o t be a l l o w e d w i t h o u t my w r i t t e n p e r m i s s i o n . Department o f The U n i v e r s i t y o f B r i t i s h Columbia 1956 Main Mall Vancouver, Canada V6T 1Y3 DE-6 (3/81) i i F e r t i l i z a t i o n o f S t a g n a t e d S i t k a S p r u c e P l a n t a t i o n s on N o r t h e r n V a n c o u v e r I s l a n d ABSTRACT E x t e n s i v e a r e a s o f S i t k a s p r u c e p l a n t a t i o n s e s t a b l i s h e d d u r i n g t h e l a s t 15 y e a r s on t h e C H - p h a s e o f t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n on n o r t h e r n V a n c o u v e r I s l a n d a r e p r e s e n t l y e x h i b i t i n g symptoms o f s e v e r e c h l o r o s i s and g r o w t h c h e c k . I n v e s t i g a t i o n s i n t o t h e p o o r p e r f o r m a n c e o f t h e s e p l a n t a t i o n s a r e d e s c r i b e d i n t h i s t h e s i s . C o m p a r i s o n s o f t h e s o i l n u t r i e n t l e v e l s b e t w e e n t h i s p o o r l y p r o d u c t i v e C H - p h a s e and t h e a d j a c e n t h i g h l y p r o d u c t i v e H A - p h a s e were m a d e . In a d d i t i o n , f e r t i l i z a t i o n s c r e e n i n g t r i a l s were e s t a b l i s h e d i n o r d e r t o i d e n t i f y p o s s i b l e l i m i t i n g n u t r i e n t s and d e t e r m i n e t h e p o t e n t i a l r e s p o n s i v e n e s s o f S i t k a s p r u c e t o f e r t i l i z a t i o n . S o i l s a m p l e s were c o l l e c t e d o v e r an age s e q u e n c e o f c u t o v e r s f r o m b o t h p h a s e s i n o r d e r t o c o m p a r e d i f f e r e n c e s i n t h e s o i l n u t r i e n t s t a t u s and t o d e t e r m i n e t h e e f f e c t s o f t i m e s i n c e h a r v e s t i n g on N m i n e r a l i z a t i o n r a t e s . S i g n i f i c a n t l y g r e a t e r a m o u n t s o f t o t a l and a v a i l a b l e P and t o t a l , KC1 e x t r a c t a b l e , and m i n e r a l i z a b l e N ( p = . 0 1 ) were f o u n d i n t h e m i n e r a l s o i l and humus o f t h e H A - p h a s e . The m i n e r a l s o i l o f t h e H A - p h a s e a l s o had i i i s i g n i f i c a n t l y h i g h e r (p=.05) c o n c e n t r a t i o n s o f e x c h a n g e a b l e K. I n a d d i t i o n , t h i s p h a s e had a s i g n i f i c a n t l y l o w e r (p=.01) C/N r a t i o . A l t h o u g h s i g n i f i c a n t d i f f e r e n c e s were n o t e d i n t h e m i n e r a l n u t r i e n t c o m p o s i t i o n o f t h e two p h a s e s , i n a l l c a s e s ( w i t h t h e p o s s i b l e e x c e p t i o n o f m i n e r a l i z a b l e N ) , t h e a b s o l u t e d i f f e r e n c e s b e t w e e n t h e two p h a s e s d i d n o t a p p e a r l a r g e enough t o a c c o u n t f o r t h e d r a m a t i c d i f f e r e n c e s i n p r o d u c t i v i t y . H a r v e s t i n g p l u s s l a s h b u r n i n g a p p e a r s t o have had l i t t l e e f f e c t on t h e r a t e s o f N m i n e r a l i z a t i o n i n t h e humus o r m i n e r a l s o i l o f t h e HA-phase. However, i n t h e CH-phase h a r v e s t i n g p l u s s l a s h b u r n i n g h a s had a s i g n i f i c a n t i n f l u e n c e on t h e m i n e r a l i z a t i o n r a t e s o f t h e humus b u t n o t o f t h e m i n e r a l s o i l . H a r v e s t i n g i n i t i a l l y r e s u l t e d i n a s i g n i f i c a n t (p=.05) i n c r e a s e i n t h e m i n e r a l i z a t i o n r a t e s , h o w e v e r , w i t h i n f i v e y e a r s t h e y r e t u r n e d t o l e v e l s c o m p a r a b l e t o t h a t o f t h e c o n t r o l . F e r t i l i z a t i o n s c r e e n i n g t r i a l s were e s t a b l i s h e d i n f i v e S i t k a s p r u c e p l a n t a t i o n s r a n g i n g i n age f r o m 8 t o 14 y e a r s . A l l p l a n t a t i o n s were g r o w i n g on t h e CH-phase and were e x h i b i t i n g symptoms o f c h l o r o s i s and g r o w t h c h e c k . Changes i n t h e f i r s t - y e a r n e e d l e d r y - w e i g h t , n e e d l e n u t r i e n t c o m p o s i t i o n , and l e a d e r g r o w t h were m o n i t o r e d . T r e a t m e n t s f o r t h e s e t r i a l s c o n s i s t e d o f a N, P, K f a c t o r i a l e x p e r i m e n t , and one s e p a r a t e t r e a t m e n t o f a c o m p l e t e n u t r i e n t m i x t u r e . E a c h t r e a t m e n t was r e p l i c a t e d s e v e n t i m e s i n e a c h o f t h e f i v e p l a n t a t i o n s . N o r N p l u s K f e r t i l i z a t i o n r e s u l t e d i n a 10% i v i n c r e a s e i n n e e d l e d r y - w e i g h t and a 25 t o 30% i n c r e a s e i n f i r s t - y e a r l e a d e r g r o w t h r e s p o n s e o v e r t h a t o f t h e c o n t r o l . P f e r t i l i z a t i o n had a s t r o n g s y n e r g i s t i c e f f e c t and when added i n c o m b i n a t i o n w i t h N o r N p l u s K r e s u l t e d i n a n e e d l e d r y - w e i g h t i n c r e a s e o f 40 t o 4 1 % and a l e a d e r g r o w t h i n c r e a s e o f 78 t o 8 3 % . A l i m i t e d s a m p l e o f n a t u r a l l y o c c u r r i n g h e m l o c k i n some o f t h e p l o t s e x h i b i t e d s i m i l a r t r e n d s , a l t h o u g h l e a d e r g r o w t h i n c r e a s e s were somewhat g r e a t e r . F e r t i l i z a t i o n w i t h P and K, a l o n e o r t o g e t h e r , had no e f f e c t on l e a d e r g r o w t h o r n e e d l e w e i g h t d e s p i t e t h e s e v e r e d e f i c i e n c i e s o f t h e s e two e l e m e n t s . However, P had a p o s i t i v e i n f l u e n c e on t h e u p t a k e o f N, K, Ca and Mg, w h e r e a s K p o s i t i v e l y a f f e c t e d Ca and d e p r e s s e d Mg. A f t e r N f e r t i l i z a t i o n , f o l i a r N c o n c e n t r a t i o n s i n c r e a s e d d r a m a t i c a l l y , r a n g i n g f r o m a mean o f 3.2% f o r t h e l o w e s t ( 2 0 0 kg N/ha) a p p l i c a t i o n r a t e t o 4.1% f o r t h e h i g h e s t ( 4 0 0 kg N/ha) a p p l i c a t i o n r a t e . The h i g h f o l i a r N c o n c e n t r a t i o n s had a s i g n i f i c a n t n e g a t i v e i n f l u e n c e on f o l i a r K c o n c e n t r a t i o n s . ' T h i s d e c l i n e i n K c o n c e n t r a t i o n s c o u l d o n l y p a r t i a l l y be a t t r i b u t e d t o a g r o w t h d i l u t i o n e f f e c t and o c c u r r e d w h e t h e r o r n o t K was a d d e d . A s i m i l a r e f f e c t on P, Ca o r Mg was n o t n o t e d . The h i g h N c o n c e n t r a t i o n s a l s o a p p e a r e d t o have had a n e g a t i v e i n f l u e n c e on b o t h n e e d l e w e i g h t and l e a d e r g r o w t h a s t h e r e was a t e n d e n c y f o r t h e r e s p o n s e o f b o t h t o d e c l i n e a s N c o n c e n t r a t i o n s i n c r e a s e d . T h e r e were s i g n i f i c a n t d i f f e r e n c e s i n b o t h l e a d e r g r o w t h and n e e d l e w e i g h t r e s p o n s e s b e tween some o f t h e p l a n t a t i o n s , b u t t r e a t m e n t s r e c e i v i n g b o t h N and P V f e r t i l i z e r s c o n s i s t e n t l y gave t h e g r e a t e s t r e s p o n s e s . The i n d i v i d u a l t r e a t m e n t , h o w e v e r , w h i c h gave t h e g r e a t e s t and most c o n s i s t e n t o v e r a l l r e s p o n s e was t h a t c o n t a i n i n g a l l m a c r o - and m i c r o - n u t r i e n t s . R e s u l t s f r o m t h i s s t u d y i n d i c a t e t h a t t h e p o o r p e r f o r m a n c e o f S i t k a s p r u c e p l a n t a t i o n s e s t a b l i s h e d on t h e CH-phase o f t h e s a l a l - m o s s e c o s y s t e m i s p a r t i a l l y due t o a s e v e r e N and P d e f i c i e n c y . T h e s e d e f i c i e n c i e s a r e a s s o c i a t e d w i t h t h e c o m p l e t e i n v a s i o n o f t h e s e c u t o v e r s by s a l a l . I t ^ h a s a l s o been shown t h a t t h e S i t k a s p r u c e i n t h e s e p l a n t a t i o n s w o u l d be h i g h l y r e s p o n s i v e t o N and P f e r t i l i z a t i o n . A l t h o u g h K d o es n o t a p p e a r t o l i m i t g r o w t h and no a p p a r e n t b e n e f i t s were g a i n e d f r o m K f e r t i l i z a t i o n , a s e v e r e N i n d u c e d K d e f i c i e n c y i s l i k e l y . v i TABLE OF CONTENTS PAGE ABSTRACT i i TABLE OF CONTENTS v i L I S T OF TABLES v i i i L I S T OF FIGURES x ACKNOWLEDGEMENTS x i i i INTRODUCTION 1 LITERATURE REVIEW 4 F o l i a r A n a l y s i s 4 S i t k a S p r u c e N u t r i t i o n and F e r t i l i z e r R e s p o n s e .... 16 STUDY AREA AND S I T E DESCRIPTION 25 L o c a t i o n 25 C l i m a t e 25 S i t e and E c o s y s t e m D e s c r i p t i o n 28 COMPARISONS OF SOIL NUTRIENT STATUS AND NITROGEN MINERALIZATION POTENTIAL OF THE CH- AND HA-PHASES 45 INTRODUCTION 45 MATERIALS AND METHODS 46 F i e l d P r o c e d u r e s 46 L a b o r a t o r y A n a l y s i s 47 S t a t i s t i c a l A n a l y s i s 48 RESULTS AND DISCUSSION 49 SUMMARY AND CONCLUSIONS 59 v i i PAGE EFFECTS OF FERTILIZATION ON 1983 LEADER GROWTH, CURRENT YEAR NEEDLE WEIGHT AND NEEDLE NUTRIENT COMPOSITION 61 INTRODUCTION 61 MATERIALS AND METHODS 63 F i e l d P r o c e d u r e s 63 L a b o r a t o r y A n a l y s i s 66 S t a t i s t i c a l A n a l y s i s 67 RESULTS AND DISCUSSION 69 E f f e c t s on Needle Weight and Leader Growth ... 69 E f f e c t s on F o l i a r N i t r o g e n 80 E f f e c t s on F o l i a r Phosphorus 88 E f f e c t s on F o l i a r P o t a s s i u m 95 E f f e c t s on F o l i a r C a l c i u m and Magnesium 105 E f f e c t s on F o l i a r S u l f u r I l l E f f e c t s on F o l i a r M i c r o - N u t r i e n t s 115 SUMMARY AND CONCLUSIONS 123 GENERAL CONCLUSIONS 125 LITERATURE CITED 128 APPENDICES 147 APPENDIX I The A n a l y s i s of V a r i a n c e and Student-Newman-K e u l s ' M u l t i p l e Range Test of I n d i v i d u a l Stands 147 APPENDIX I I E f f e c t s of F e r t i l i z a t i o n on Needle N u t r i e n t C o m p o s i t i o n and Needle Weight f o r Each Stand . 160 v i i i L I S T OF T A B L E S P A G E T A B L E 1 . F o l i a r n u t r i e n t c o n c e n t r a t i o n s a s s o c i a t e d w i t h g o o d a n d p o o r g r o w t h o f S i t k a s p r u c e , w e s t e r n h e m l o c k a n d w e s t e r n r e d c e d a r 2 0 T A B L E 2 . T e m p e r a t u r e a n d p r e c i p i t a t i o n f o r P o r t H a r d y . 2 7 T A B L E 3 . S o i l p r o f i l e d e s c r i p t i o n o f t h e C H - p h a s e . . . . . 3 9 T A B L E 4 . S o i l p r o f i l e d e s c r i p t i o n o f t h e H A - p h a s e 4 0 T A B L E 5 . P h y s i c a l a n d c h e m i c a l d e s c r i p t i o n o f s o i l p r o f i l e s f r o m t h e C H - a n d H A - p h a s e s 4 1 T A B L E 6 . C o m p a r i s o n o f n u t r i e n t c o n t e n t s i n t h e C H - a n d H A - p h a s e s a v e r a g e d o v e r a l l c u t o v e r s . V a l u e s i n p a r e n t h e s i s a r e jf SD 5 1 T A B L E 7 . E s t i m a t e s o f s o i l n u t r i e n t c o n t e n t s i n t h e C H - p h a s e a n d t h e H A - p h a s e a n d i n o t h e r s o i l s o f V a n c o u v e r I s l a n d . V a l u e s i n p a r e n t h e s i s a r e r a n g e s 5 2 T A B L E 8 . E s t i m a t e s o f m i n e r a l i z a b l e N f o r a v a r i e t y o f s i t e s t h r o u g h o u t t h e P a c i f i c N o r t h w e s t a n d i n B r i t a i n 5 7 T A B L E 9 . S t a n d c h a r a c t e r i s t i c s o f f i v e S i t k a s p r u c e p l a n t a t i o n s s e l e c t e d f o r f e r t i l i z a t i o n 6 3 T A B L E 1 0 . R a t e s o f a p p l i c a t i o n i n k g / h a f o r m a c r o - a n d m i c r o - n u t r i e n t m i x t u r e 6 5 T A B L E 1 1 . A n a l y s i s o f v a r i a n c e o f f i r s t y e a r l e a d e r g r o w t h , n e e d l e d r y - w e i g h t , a n d n e e d l e n u t r i e n t c o n c e n t r a t i o n a n d c o n t e n t 7 0 T A B L E 1 2 . P e r c e n t c h a n g e f r o m c o n t r o l i n n e e d l e d r y -w e i g h t a n d 1 9 8 3 l e a d e r g r o w t h f o r e a c h s t a n d . . 7 3 T A B L E 1 3 . 1 9 8 3 l e a d e r g r o w t h r e s p o n s e s o f s a m p l e d h e m l o c k . T r e a t m e n t s c o n n e c t e d b y t h e s a m e l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 7 9 i x PAGE T A B L E 14, T A B L E 15, T A B L E 16, T A B L E 17, T A B L E 18, W i t h i n and b e t w e e n s p e c i e s c o m p a r i s o n s o f mean f o l i a r N c o n c e n t r a t i o n s (% o v e n - d r y w e i g h t ) f o r s p r u c e , h e m l o c k and c e d a r . T r e a t m e n t s c o n n e c t e d by t h e same l i n e o r f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 , 81 W i t h i n and b e t w e e n s p e c i e s c o m p a r i s o n o f mean f o l i a r P c o n c e n t r a t i o n s (% o v e n - d r y w e i g h t ) f o r s p r u c e , h e m l o c k and c e d a r . T r e a t m e n t s c o n n e c t e d by t h e same l i n e o r f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 , 92 Mean f o l i a r K c o n c e n t r a t i o n s o f S i t k a s p r u c e and h e m l o c k . T r e a t m e n t s c o n n e c t e d by t h e same l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 A p p l i c a b l e t o s p r u c e o n l y 104 Mean f o l i a r Ca and Mg c o n c e n t r a t i o n o f S i t k a s p r u c e and h e m l o c k . T r e a t m e n t s c o n n e c t e d by t h e same l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 . A p p l i c a b l e t o s p r u c e o n l y 110 C o m p a r i s o n o f f o l i a r m i c r o - n u t r i e n t c o n c e n t r a t i o n w i t h e s t i m a t e s f r o m L i t e r a t u r e . A l l v a l u e s i n ppm 121 X LIST OF FIGURES PAGE FIGURE 1 FIGURE 2, FIGURE 3, FIGURE 4, FIGURE 5, FIGURE 6, FIGURE 7, FIGURE 8, FIGURE 9, T h e o r e t i c a l r e l a t i o n s h i p between growth and f o l i a r n u t r i e n t c o n t e n t r a t i o n Schematic r e l a t i o n s h i p s between needle n u t r i e n t c o n c e n t r a t i o n , c o n t e n t and n e e d l e dry weight f o l l o w i n g f e r t i l i z a t i o n (Morrow, 1979) L o c a t i o n of study a r e a 13 26 Mature s t a n d s of the HA- and CH-phases a) HA-phase, t h i s s t a n d i s a p p r o x i m a t e l y 70 y e a r s o l d and o r i g i n a t e d from the 1906 blowdown. CH-phase, t h i s s t a n d i s uneven aged (140-300+ y e a r s ) and has developed w i t h l i t t l e or no d i s t u r b a n c e , b) 31 Development of p l a n t a t i o n s on the HA- and CH-phases a f t e r l o g g i n g . R i c k F o u r n i e r i s seen here s t a n d i n g i n two p l a n t a t i o n s which were both e s t a b l i s h e d i n 1973. These photos were taken a p p r o x i m a t e l y 40 m a p a r t , a) HA-phase b) CH-phase 34 I l l u s t r a t i o n of growth p a t t e r n s f o r S i t k a spruce growing on the CH-phase 35 Mean c u m u l a t i v e h e i g h t growth of S i t k a spruce on the CH- and HA-phases. Means a r e based on 14 and 10 sample t r e e s f o r the CH- and HA-phases, r e s p e c t i v e l y 36 T y p i c a l s o i l p r o f i l e s of the HA- and CH-phases. P r o f i l e s shown were dug on the same day and occupy the same r e l a t i v e t o p o g r a p h i c l o c a t i o n . a) HA-phase b) CH-phase ...... 38 N m i n e r a l i z a t i o n r a t e s of the FH l a y e r and m i n e r a l s o i l of the HA-phase ( ) and the CH-phase ( ). L i n e s c o n n e c t i n g the same p o i n t s are not s i g n i f i c a n t l y d i f f e r e n t . V e r t i c a l b a r s + 1 SD 56 x i PAGE F IGURE 1 0 . N e e d l e w e i g h t r e s p o n s e . T r e a t m e n t s c o n n e c t e d by t h e same l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 . V e r t i c a l b a r s + 1 SD . . . 72 F IGURE 1 1 . L e a d e r g r o w t h r e s p o n s e . T r e a t m e n t s c o n n e c t e d by t h e same l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 72 F IGURE 1 2 . N x P i n t e r a c t i o n e f f e c t s on 1983 l e a d e r g r o w t h and n e e d l e w e i g h t . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 74 F IGURE 1 3 . R e l a t i o n s h i p b e t w e e n f o l i a r N c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 84 F IGURE 1 4 . E f f e c t s o f N x P i n t e r a c t i o n on N u p t a k e . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 86 F IGURE 1 5 . E f f e c t s o f N x P i n t e r a c t i o n on P c o n c e n t r a t i o n . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 89 F IGURE 1 6 . R e l a t i o n s h i p b e t w e e n f o l i a r P c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 93 F IGURE 1 7 . E f f e c t s o f N x P and N x K i n t e r a c t i o n s on p o t a s s i u m c o n c e n t r a t i o n . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 97 F IGURE 1 8 . E f f e c t s o f N x P and N x K i n t e r a c t i o n s on p o t a s s i u m c o n t e n t . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 98 F IGURE 1 9 . R e l a t i o n s h i p b e t w e e n f o l i a r K c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 99 F IGURE 2 0 a . S i t k a s p r u c e e x h i b i t i n g b r o n z i n g o r s c o r c h i n g o f f o l i a g e p r i o r t o f e r t i l i z a t i o n b . S i t k a s p r u c e e x h i b i t i n g symptoms o f K d e f i c i e n c y a f t e r f e r t i l i z a t i o n w i t h 300 kg N, 50 kg P and 50 kg K 102 F IGURE 2 1 . R e l a t i o n s h i p b e t w e e n f o l i a r Ca c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 106 F IGURE 2 2 . R e l a t i o n s h i p b e t w e e n f o l i a r Mg c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 107 x i i PAGE F IGURE 2 3 . E f f e c t s o f N x P i n t e r a c t i o n on Ca and Mg c o n t e n t . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 . . . . 109 F IGURE 2 4 . R e l a t i o n s h i p b e t w e e n f o l i a r S c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 113 F IGURE 2 5 . R e l a t i o n s h i p b e t w e e n f o l i a r B c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 116 F IGURE 2 6 . R e l a t i o n s h i p b e t w e e n f o l i a r Cu c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 117 F IGURE 2 7 . R e l a t i o n s h i p b e t w e e n f o l i a r Mn c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 118 F IGURE 2 8 . R e l a t i o n s h i p b e t w e e n f o l i a r Zn c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t 119 x i i i A C K N O W L E D G E M E N T S I w o u l d l i k e t o t h a n k t h e m a n y p e o p l e w h o h e l p e d t h r o u g h o u t t h i s t h e s i s . T h e a s s i s t a n c e o f R i c h a r d F o u r n i e r a n d N a n c y R o g e r s i n c a r r y i n g o u t t h e m a n y h o u r s o f p h y s i c a l l y d e m a n d i n g f i e l d w o r k w a s g r e a t l y a p p r e c i a t e d . S i m i l a r l y , t h e l a b o r a t o r y a n a l y s i s c o u l d n o t h a v e b e e n c o m p l e t e d w i t h o u t t h e a d v i s e a n d c o o p e r a t i o n o f M i n T z e a n d h i s w i f e E v a . S p e c i a l t h a n k s g o t o D r . J o h n B a r k e r a n d B i l l D u m o n t o f W e s t e r n F o r e s t P r o d u c t s C o . L t d . f o r t h e i r m o r a l s u p p o r t a n d f i n a n c i a l a s s i s t a n c e i n p r o v i d i n g m u c h o f t h e m a t e r i a l s n e c e s s a r y f o r t h i s t h e s i s . I w o u l d l i k e t o t h a n k my c o m m i t t e e m e m b e r s f o r t h e i r h e l p f u l r e v i e w s o f t h e t h e s i s m a n u s c r i p t . A s p e c i a l t h a n k s h o w e v e r , m u s t b e e x t e n d e d t o D r . V a l i n M a r s h a l l o f t h e P a c i f i c F o r e s t R e s e a r c h C e n t r e f o r t h e m a n y h o u r s o f d i s c u s s i o n s a n d e n c o u r a g e m e n t w h i c h h e g a v e . T h e a s s i s t a n c e a n d e n c o u r a g e m e n t o f my t h e s i s a d v i s o r , D r . G o r d o n W e e t m a n , i s a l s o g r a t e f u l l y a c k n o w l e d g e d . F i n a l l y , I w o u l d l i k e t o t h a n k my w i f e , J u d y , f o r r e v i e w i n g . a n d t y p i n g t h e m a n u s c r i p t a n d f o r h e r e n c o u r a g e m e n t a n d p a t i e n c e t h r o u g h o u t t h i s t h e s i s . - 1 -INTRODUCTION Con s i d e r a b l e a t t e n t i o n has r e c e n t l y been focused on the poor performance of S i t k a spruce ( P i c e a s i t c h e n s i s (Bong.) Carr.) p l a n t a t i o n s on the cedar-hemlock phase of the salal-moss ecosystem a s s o c i a t i o n d e s c r i b e d by Lewis'(1982). Although these p l a n t a t i o n s had i n i t i a l l y performed w e l l i n both height growth and s u r v i v a l , they are now e x p e r i e n c i n g a severe d e c l i n e . P r e s e n t l y , the annual height increment of the S i t k a spruce i n many of these p l a n t a t i o n s only averages about 10 cm and the t r e e s are now extremely c h l o r o t i c . Over 1900 ha of S i t k a spruce p l a n t a t i o n s have been e s t a b l i s h e d on the salal-moss, and the s i m i l a r but wetter, cedar-skunk cabbage ecosystem a s s o c i a t i o n i n Block 4 of Tree Farm Lic e n c e 25 (T.F.L. 25) ( F i g u r e 3 ) . The p o t e n t i a l f o r s i m i l a r p l a n t a t i o n f a i l u r e s throughout c o a s t a l B r i t i s h Columbia may be c o n s i d e r a b l y g r e a t e r , s i n c e these ecosystem a s s o c i a t i o n s , or very s i m i l a r ones, p r e s e n t l y supporting old-growth cedar-hemlock stands are common. To date, l i t t l e - a t t e n t i o n has been paid to the n u t r i t i o n a l aspects of these s i t e s and t h e i r c a p a b i l i t y to support second growth p l a n t a t i o n s a f t e r h a r v e s t i n g . ''Terry Lewis, 1982. Ecosystems of the Port M c N e i l l block (Block 4) of Tree Farm Lic e n c e 25. Unpublished I n t e r n a l r e p o r t , Western F o r e s t Products L t d . . - 2 -T h e p o o r p e r f o r m a n c e o f t h e p l a n t a t i o n s e s t a b l i s h e d o n t h e c e d a r - h e m l o c k p h a s e b e c o m e s e v e n m o r e d r a m a t i c w h e n c o m p a r e d t o t h e g o o d g r o w t h p e r f o r m a n c e s o f t h e s p r u c e p l a n t a t i o n s e s t a b l i s h e d o n t h e h i g h l y p r o d u c t i v e h e m l o c k - a m a b i l i s f i r p h a s e , a l s o o f t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n ( S e e p a g e s 2 8 t o 4 4 f o r a c o m p l e t e d e s c r i p t i o n a n d d i s c u s s i o n o f b o t h p h a s e s ) . A l t h o u g h t h e s e t w o p h a s e s o f t e n o c c u r c o n t i g u o u s t o e a c h o t h e r , t h e p l a n t a t i o n s o f t h e h e m l o c k - a m a b i l i s f i r p h a s e h a v e n o t e x p e r i e n c e d t h e d e c l i n e i n g r o w t h c o m m o n l y a s s o c i a t e d w i t h t h e p l a n t a t i o n s o f t h e c e d a r - h e m l o c k p h a s e . L e w i s ( 1 9 8 2 ) s u g g e s t e d t h a t t h e d i f f e r e n c e s i n p r o d u c t i v i t y b e t w e e n t h e t w o p h a s e s w e r e r e l a t e d t o t h e d i f f e r e n c e s i n t h e i r d e v e l o p m e n t h i s t o r i e s . L e w i s h y p o t h e s i z e d t h a t t h e l a c k o f d r a m a t i c d i s t u r b a n c e s t o t h e m a t u r e s t a n d s o f t h e c e d a r - h e m l o c k p h a s e , s u c h a s t h e p e r i o d i c w i n d t h r o w d i s t u r b a n c e s w h i c h i s b e l i e v e d t o o c c u r t o t h e m a t u r e s t a n d s o f t h e h e m l o c k - a m a b i l i s f i r p h a s e , h a s l e d t o a g r a d u a l d e c l i n e i n o r g a n i c m a t t e r d e c o m p o s i t i o n a n d n u t r i e n t t u r n o v e r a n d t h u s , p r o d u c t i v i t y o f t h i s s i t e . He s u g g e s t e d t h a t t h e k e y t o i m p r o v e d ' p r o d u c t i v i t y l a y i n t h e m a n a g e m e n t o f t h e s u r f a c e o r g a n i c l a y e r a n d b e l i e v e d t h a t t h i s w o u l d b e s t b e a c h i e v e d b y s c a r i f i c a t i o n . . W h i l e t h i s a p p r o a c h may b e f e a s i b l e f o r f u t u r e c u t o v e r s , i t i s n o t a c c e p t a b l e f o r e x i s t i n g p l a n t a t i o n s , s i n c e , d e s p i t e t h e i r g r o w t h c h e c k , e v e n t h e y o u n g e s t p l a n t a t i o n s a r e a p p r o a c h i n g t w o m e t r e s i n h e i g h t . I n a d d i t i o n , a s L e w i s n o t e d , t h e r e i s s o m e q u e s t i o n a s t o - 3 -w h e t h e r a s i n g l e d i s t u r b a n c e w o u l d b e s u f f i c i e n t t o e n s u r e c o n t i n u e d p r o d u c t i v i t y t h r o u g h o u t t h e e n t i r e r o t a t i o n . I n f a c t , t h e r e i s i n c r e a s i n g e v i d e n c e t o s u g g e s t t h a t o n s o m e s i t e s , g r o w t h b e n e f i t s f r o m s c a r i f i c a t i o n a r e s h o r t - l i v e d ( R o s s a n d M a l c o l m , 1 9 8 2 ; T i a r k s , 1 9 8 3 ) . T h u s i f p r o d u c t i v i t y i s t o b e m a i n t a i n e d , a d d i t i o n a l t r e a t m e n t s s u c h a s f e r t i l i z a t i o n may b e r e q u i r e d . T h e r e f o r e , i t i s i m p o r t a n t t o k n o w w h a t b e n e f i t s may b e d e r i v e d f r o m f e r t i l i z a t i o n a n d w h i c h n u t r i e n t s w o u l d m o s t l i k e l y s t i m u l a t e g r o w t h . T h i s k n o w l e d g e w i l l p r o v i d e g u i d e l i n e s f o r t h e m a n a g e m e n t o f f u t u r e p l a n t a t i o n s a n d may a l s o p r o v i d e a s o l u t i o n t o t h e p r e s e n t p r o b l e m o f s t a g n a t i o n . T h i s s t u d y w i l l a d d r e s s s o m e o f t h e q u e s t i o n s c o n c e r n i n g t h e p o o r p e r f o r m a n c e o f S i t k a s p r u c e p l a n t a t i o n s o n t h e c e d a r - h e m l o c k p h a s e o f t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n . S p e c i f i c a l l y , t h e o b j e c t i v e s w i l l b e t o : 1 . D e t e r m i n e w h i c h n u t r i e n t ( s ) a r e p r e s e n t l y d e f i c i e n t a n d l i m i t i n g g r o w t h o n t h e c e d a r -h e m l o c k p h a s e . 2 . I d e n t i f y t h e p o t e n t i a l r e s p o n s i v e n e s s o f t h e S i t k a s p r u c e t o f e r t i l i z a t i o n . 3 . C o m p a r e t h e d i f f e r e n c e s o f t h e t w o p h a s e s o f t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n a n d t o p r o v i d e p l a u s i b l e e x p l a n a t i o n s f o r t h e d r a m a t i c d i f f e r e n c e s i n p r o d u c t i v i t y . -4-LITERATURE REVIEW F o l i a r A n a l y s i s A c o n s i d e r a b l e body of l i t e r a t u r e p r e s e n t l y e x i s t s on the u s e s , m e r i t s and problems a s s o c i a t e d w i t h f o l i a r a n a l y s i s . S i n c e much of t h i s work has a l r e a d y been summarized i n a number o f e x c e l l e n t r e v i e w s , n o t a b l y S m i t h , 1962; L e a f , 1973; M o r r i s o n , 1974; van den D r i e s s c h e , 1974; and Turner e t a l . , 1978, i t i s f e l t t h a t a d e t a i l e d r e i t e r a t i o n of t h i s work i s not n e c e s s a r y . However, s i n c e much of t h i s t h e s i s i s based on the i n t e r p r e t a t i o n of f o l i a r a n a l y s i s , a b r i e f r e v i e w , p a r t i c u l a r l y of the more r e c e n t l i t e r a t u r e i s g i v e n . The use of f o l i a r a n a l y s i s l i e s i n the b e l i e f t h a t the p l a n t i t s e l f i s the best i n t e g r a t o r of a l l f a c t o r s a f f e c t i n g i t s m i n e r a l n u t r i e n t s t a t u s ( B a l l a r d , R., 1979; Maynard, 1982). Changes i n the p l a n t environment, e x t e r n a l or i n t e r n a l , a r e u s u a l l y r e a d i l y r e f l e c t e d i n the c o n c e n t r a t i o n of some or a l l of the f i f t e e n e s s e n t i a l e l e m e n t s found i n the f o l i a g e . R i c h a r d s and Bevege (1972) i d e n t i f i e d two uses of f o l i a r a n a l y s i s : ( i ) — a d i a g n o s t i c t o o l f o r i d e n t i f y i n g n u t r i e n t d i s o r d e r s , and ( i i ) — a p r e d i c t i v e t o o l f o r d e t e r m i n i n g p o s s i b l e growth responses t o f e r t i l i z a t i o n . I t has been used e x t e n s i v e l y i n a g r i c u l t u r e f o r both purposes, -5-h o w e v e r i n f o r e s t r y , w h i l e f o l i a r a n a l y s i s i s a c c e p t e d a n d u s e d r o u t i n e l y a s a d i a g n o s t i c t o o l , i t i s g e n e r a l l y c o n s i d e r e d t o b e t o o i m p r e c i s e t o q u a n t i t a t i v e l y p r e d i c t f e r t i l i z e r r e s p o n s e s ( v a n d e n D r i e s s c h e , 1 9 7 4 ; B a l l a r d , R . , 1 9 7 9 ) . H o w e v e r , f o l i a r a n a l y s i s h a s u s u a l l y b e e n f o u n d t o b e b e t t e r c o r r e l a t e d w i t h f e r t i l i z e r r e s p o n s e s t h a n s o i l a n a l y s i s a n d t h e r e f o r e i t t e n d s t o b e u s e d m o r e o f t e n ( B a l l a r d , R . , 1 9 7 9 ) . M a n y o f t h e f a c t o r s c o n t r i b u t i n g t o t h e i m p r e c i s i o n o f f o l i a r a n a l y s i s i n b o t h i t s d i a g n o s t i c a n d p r e d i c t i v e a p p l i c a t i o n s a r e w e l l k n o w n , b u t t h e c o n t r o l o f t h e s e a r e d i f f i c u l t a n d s t i l l u n d e r i n v e s t i g a t i o n . S o m e o f t h e s e f a c t o r s a r e : ( i ) C r i t i c a l n u t r i e n t l e v e l s : F o r m a n y n u t r i e n t s a n d s p e c i e s , s t a t i s t i c a l l y e s t a b l i s h e d c r i t i c a l n u t r i e n t l e v e l s a n d g r o w t h r e s p o n s e c u r v e s h a v e n o t b e e n d e t e r m i n e d . E v e n w h e r e s i g n i f i c a n t r e l a t i o n s h i p s h a v e b e e n d e v e l o p e d , t h e y a r e u s u a l l y n o t s e n s i t i v e e n o u g h t o i d e n t i f y m a r g i n a l d e f i c i e n c i e s . A s a r e s u l t , t h e a b i l i t y o f f o l i a r a n a l y s i s t o i d e n t i f y p o t e n t i a l l y r e s p o n s i v e s i t e s t e n d s t o b e g o o d o n l y i n t h e v e r y d e f i c i e n t r a n g e ( B a l l a r d , R . , 1 9 7 9 ) . ( i i ) W i t h i n — t r e e v a r i a b i l i t y : A c o n s i d e r a b l e . - a m o u n t o f i n h e r e n t v a r i a b i l i t y e x i s t s w i t h i n t h e t r e e . W h i l e m u c h o f t h i s v a r i a b i l i t y may b e . o v e r c o m e t h r o u g h s t a n d a r d i z a t i o n o f s a m p l i n g m e t h o d s , t h e r e i s s t i l l s o m e d e b a t e o v e r w h i c h m e t h o d s s h o u l d b e a d o p t e d . F o r e x a m p l e , f o r m a n y o f t h e c o n i f e r o u s s p e c i e s i n t h e T e m p e r a t e a n d B o r e a l f o r e s t r e g i o n s , i t i s g e n e r a l l y a c c e p t e d t h a t f o l i a g e - 6 -s a m p l i n g f o r f o l i a r a n a l y s i s be done i n t h e f a l l and be r e s t r i c t e d t o t h e c u r r e n t y e a r ' s f o l i a g e f r o m t h e u p p e r p o r t i o n o f t h e c r o w n ( B a l l a r d , T . f 1 9 7 9 ) . W a r i n g and Y o u n g b e r g ( 1 9 7 2 ) h o w e v e r , a r g u e d t h a t s a m p l i n g d u r i n g t h e p e r i o d o f most a c t i v e g r o w t h w o u l d p r o v i d e a more s e n s i t i v e i n d i c a t o r o f p o s s i b l e n u t r i e n t d e f i c i e n c i e s . T h i s same s e n t i m e n t h a s r e c e n t l y b e e n e c h o e d by Mor row and T immer ( 1 9 8 1 ) and P o w e r s ( 1 9 8 3 ) , a l l o f whom a l s o s u g g e s t e d t h a t s a m p l i n g o f c u r r e n t p l u s o n e - y e a r - o l d n e e d l e s c o u l d g r e a t l y i m p r o v e f o l i a r d i a g n o s i s . B a l l a r d , R. ( 1 9 7 9 ) n o t e d t h a t many r e s e a r c h e r s do n o t f u l l y a p p r e c i a t e an e l e m e n t s ' p h y s i o l o g i c a l f u n c t i o n and b e h a v i o u r . T h u s , many o f t h e s a m p l i n g and a n a l y t i c a l t e c h n i q u e s d e v e l o p e d i n f o l i a r a n a l y s i s may n o t p r o v i d e a good i n d e x o f t h e n u t r i e n t s t a t u s o f t h e t r e e . ( i i i ) F e r t i l i z e r — i n d u c e d i n t e r a c t i o n s : P a s t r e s e a r c h e r s h a v e o f t e n f a i l e d t o r e c o g n i z e some o f t h e f e r t i l i z e r — i n d u c e d i n t e r a c t i o n s w h i c h r e g u l a t e p o t e n t i a l r e s p o n s e s . E x a m p l e s o f t h e s e w o u l d be t h e s t o c k i n g x f e r t i l i z e r r e s p o n s e i n t e r a c t i o n w h i c h h a s been shown t o s t r o n g l y r e g u l a t e t h e r e s p o n s e o f s t a n d s t o n i t r o g e n f e r t i l i z a t i o n ( B a l l a r d , R . , 1 9 7 9 ) , o r t h e s p e c i e s x n i t r o g e n s o u r c e i n t e r a c t i o n w h i c h h a s b e e n s u g g e s t e d a s a p o s s i b l e r e a s o n f o r t h e d i f f e r e n t i a l r e s p o n s e s o f w e s t e r n h e m l o c k ( T s u g a h e t e r o p h y l l a ( R a f . ) S a r g . ) s t a n d s t o n i t r o g e n o u s f e r t i l i z e r s ( W e b s t e r e t a l . , 1 9 7 6 ; G i l l and L a v e n d e r , 1 9 8 3 a ) . ( i v ) F o r e s t s t a n d v a r a b i l i t y : C o n v e n t i o n a l m e t h o d s o f m e a s u r i n g g r o w t h r e s p o n s e s f r o m f e r t i l i z e r t r i a l s u s u a l l y c o n s i s t o f c o m p a r i n g d i f f e r e n c e s i n g r o w t h o f t h e c o n t r o l - 7 -p l o t s t o t h a t o f f e r t i l i z e d p l o t s ( S a l o n i u s and M a h e n d r a p p a , 1 9 8 3 ) . Numerous e m p i r i c a l t r i a l s h a v e shown t h a t r e s e a r c h p l o t s a r e s e l d o m s i m i l a r , and t h e n a t u r a l v a r i a t i o n o c c u r r i n g i n f o r e s t e c o s y s t e m s c a n o f t e n mask p o t e n t i a l f e r t i l i z e r r e s p o n s e s (Shumway and A t k i n s o n , 1 9 7 7 ; O l s o n e t a l . , 1 9 7 9 ) . A t t e m p t s t o i m p r o v e t h e p r e d i c t a b i l i t y o f g r o w t h r e s p o n s e s h a s l e d r e s e a r c h e r s t o e x a m i n e a l t e r n a t i v e m e t h o d s . S a l o n i u s and M a h e n d r a p p a ( 1 9 8 3 ) s u g g e s t e d t h a t s i n c e t h e p a s t g r o w t h p e r f o r m a n c e o f a t r e e was a good i n d i c a t o r o f p o s s i b l e f u t u r e g r o w t h , e a c h t r e e c o u l d be u s e d a s i t s own c o n t r o l . T h e y e x p r e s s e d g r o w t h r e s p o n s e by e s t a b l i s h i n g a r a t i o o f t h e 1 0 - y e a r p o s t - f e r t i l i z a t i o n r a d i a l g r o w t h t o t h e 1 0 - y e a r p r e - f e r t i l i z a t i o n r a d i a l g r o w t h f o r e a c h t r e a t m e n t . Shumway and A t k i n s o n ( 1 9 7 7 ) s u g g e s t e d u s i n g an i n d i v i d u a l t r e e a p p r o a c h where t r e e p a i r s , one f e r t i l i z e d and one n o t f e r t i l i z e d , o f s i m i l a r a t t r i b u t e s a r e c o m p a r e d . ( v ) G r o w t h p a r a m e t e r s e l e c t i o n : F e r t i l i z e r r e s p o n s e s and d e g r e e o f c o r r e l a t i o n w i t h f o l i a r n u t r i e n t l e v e l s a r e a l s o a f f e c t e d by t h e g r o w t h p a r a m e t e r b e i n g m e a s u r e d . M a d g w i c k ( 1 9 6 4 ) n o t e d t h a t f o l i a r P c o n c e n t r a t i o n s c o r r e l a t e d w e l l w i t h t o t a l h e i g h t b u t n o t w i t h l e a d e r l e n g t h i n r e d p i n e ( P i n u s r e s i n o s a A i t . ) . More r e c e n t l y , C o m e r f o r d ; e t a l . ( 1 9 8 0 ) showed t h a t d i f f e r e n t m e a s u r e s o f g r o w t h ( r a d i a l , b a s a l a r e a , h e i g h t , v o l u m e , b i o m a s s , and s p e c i f i c v o l u m e ) g a v e d i f f e r e n t r e s u l t s f o r t h e l o n g e v i t y and m a g n i t u d e o f r e s p o n s e o f r e d p i n e t o K f e r t i l i z a t i o n . I t i s a p p a r e n t t h a t i m p r o v e d m e n s u r a t i o n t e c h n i q u e s and a b e t t e r u n d e r s t a n d i n g o f t h e p h y s i o l o g i c a l r e l a t i o n s h i p s b e t w e e n t h e - 8 -e l e m e n t s and t h e v a r i o u s g r o w t h p a r a m e t e r s may e v e n t u a l l y l e a d t o b e t t e r c o r r e l a t i o n s b e t w e e n f o l i a r n u t r i e n t l e v e l s and f e r t i l i z e r r e s p o n s e s . The b a s i s f o r t h e u s e o f f o l i a r a n a l y s i s l i e s i n t h e r e l a t i o n s h i p b e t w e e n f o l i a r n u t r i e n t l e v e l s and g r o w t h . T h i s r e l a t i o n s h i p , i l l u s t r a t e d i n F i g u r e 1 , i s o f t e n d e s c r i b e d a s one o f " d i m i n i s h i n g r e t u r n s " ( M a c y , 1 9 3 6 ; R i c h a r d s and B e v e g e , 1 9 7 2 ) . V a r i o u s m o d i f i c a t i o n s t o t h i s c u r v e h a v e b e e n made t o b e t t e r d e s c r i b e t h e r e l a t i o n s h i p ( R i c h a r d s and B e v e g e , 1 9 7 2 ) . The o r i g i n a l M i t s c h e r l i c h e q u a t i o n i s f r e q u e n t l y a l t e r e d t o i n c l u d e a " d e p r e s s i o n f a c t o r " t o a c c o u n t f o r t o x i c i t y a t s u p r a - o p t i m u m n u t r i e n t l e v e l s (D t o E , F i g u r e 1 ) . L e y t o n ( 1 9 5 8 ) s u g g e s t e d t h a t a s i m p l e p a r a b o l a c o u l d be u s e d a s a good a p p r o x i m a t i o n o f t h e M i t s c h e r l i c h e q u a t i o n . S t e e n b j e r g ( 1 9 5 2 ) s u g g e s t e d a s i g m o i d a l r e l a t i o n s h i p may e x i s t a t t h e l o w e r end o f t h e c u r v e w h i c h w o u l d a c c o u n t f o r an i n i t i a l d i l u t i o n e f f e c t due t o l a r g e g r o w t h r e s p o n s e s . A much more r a d i c a l d e p a r t u r e f r o m t h i s t r a d i t i o n a l c u r v e h a s r e c e n t l y b e e n p r o p o s e d by I n g e s t a d ( 1 9 7 7 , 1 9 7 9 ) . He s u g g e s t s t h a t t h e " d i m i n i s h i n g r e t u r n " t y p e c u r v e s a r e an a r t i f a c t o f t h e e x p e r i m e n t a l d e s i g n and t h a t t h e g r o w t h c u r v e f o r n i t r o g e n was b e s t d e s c r i b e d by an i n c r e a s i n g e x p o n e n t i a l f u n c t i o n r a t h e r t h a n a d e c r e a s i n g l o g a r i t h m i c f u n c t i o n . I n t e r p r e t a t i o n s o f f o l i a r a n a l y s i s h o w e v e r , a r e u s u a l l y b a s e d on t h e r e l a t i o n s h i p d e s c r i b e d by t h e c o n v e n t i o n a l c u r v e s . T h e s e c u r v e s a r e t y p i c a l l y d i v i d e d i n t o r e g i o n s o f d e f i c i e n c y , c r i t i c a l , l u x u r y and t o x i c i t y . Macy - 9 -I o CD CO < LU o D INCREASING CONCENTRATION OF LIMITING ELEMENT > FIGURE 1. T h e o r e t i c a l r e l a t i o n s h i p b e t ween g r o w t h and f o l i a r n u t r i e n t c o n c e n t r a t i o n . ( 1 9 3 6 ) f e l t t h a t t h e key t o i n t e r p r e t i n g s u c h a r e l a t i o n s h i p l a y i n t h e f a c t t h a t t h e r e was a c r i t i c a l l e v e l ( P o i n t C, F i g u r e 1) f o r e a c h n u t r i e n t , b e l o w w h i c h t h e r e was " p o v e r t y - a d j u s t m e n t " (B t o C, F i g u r e 1) and a b o v e , " l u x u r y c o n s u m p t i o n " (C t o D, F i g u r e 1 ) . Macy's zo n e o f p o v e r t y a d j u s t m e n t c o r r e s p o n d s t o t h e d e f i c i e n c y r e g i o n o f n u t r i e n t s i n p l a n t s p e c i e s . A c c o r d i n g t o t h e n e a r l i n e a r r e l a t i o n s h i p o f t h e c u r v e w i t h i n t h i s r e g i o n , an i n c r e a s e i n t h e f o l i a r c o n c e n t r a t i o n o f t h e - 1 0 -l i m i t i n g n u t r i e n t s h o u l d r e s u l t i n an a l m o s t p r o p o r t i o n a l i n c r e a s e i n g r o w t h o r y i e l d u n t i l t h e c r i t i c a l n u t r i e n t l e v e l i s r e a c h e d . T r e e s w i t h f o l i a r n u t r i e n t c o n c e n t r a t i o n s i n t h i s r a n g e w o u l d n o r m a l l y be e x p e c t e d t o r e s p o n d t o f e r t i l i z a t i o n ( P r i t c h e t t , 1 9 7 9 ) . L u x u r y c o n s u m p t i o n on t h e o t h e r hand i s n o t s u p p o s e t o r e s u l t i n any i n c r e a s e i n y i e l d ( M a c y , 1 9 3 6 ) . T h i s b e l i e f a p p e a r s t o h a v e l a r g e l y o r i g i n a t e d f r o m a g r i c u l t u r a l r e s e a r c h and g r e e n h o u s e and p o t t r i a l s on s e e d l i n g s . I n f o r e s t e c o s y s t e m s , h o w e v e r , l u x u r y c o n s u m p t i o n , t h r o u g h i n t e r n a l r e t r a n s l o c a t i o n o f n u t r i e n t s , may be one m e c h a n i s m by w h i c h p r o l o n g e d g r o w t h r e s p o n s e s c a n be o b t a i n e d f r o m f e r t i l i z a t i o n ( M i l l e r , 1 9 8 1 ) . The c r i t i c a l p e r c e n t a g e i d e n t i f i e d by Macy ( 1 9 3 6 ) h a s l e d t o t h e d e v e l o p m e n t o f t h e c r i t i c a l n u t r i e n t l e v e l c o n c e p t . T h i s c o n c e p t i s b a s e d on t h e p r e m i s e t h a t t h e c o n c e n t r a t i o n o f a p a r t i c u l a r n u t r i e n t i s an u n i q u e m e a s u r e o f g r o w t h p r o v i d e d t h a t i t i s t h e o n l y l i m i t i n g f a c t o r ( L e y t o n , 1 9 5 8 ) . W h i l e Macy b e l i e v e d t h a t t h e c r i t i c a l p e r c e n t a g e o f e a c h n u t r i e n t c o u l d be i d e n t i f i e d by a d e f i n i t e p o i n t , i t i s now g e n e r a l l y a c c e p t e d t h a t t h e r e i s no s i n g l e o p t i m u m o r c r i t i c a l c o n c e n t r a t i o n , b u t r a t h e r , a c e r t a i n i d e n t i f i a b l e r a n g e ( F a r r e t a l . , 1 9 7 7 ) . The u s e o f t h e c r i t i c a l n u t r i e n t c o n c e p t a s s u m e s t h a t t h e r e l a t i o n s h i p b e t w e e n f o l i a r n u t r i e n t c o n c e n t r a t i o n s and g r o w t h i s r e l a t i v e l y c o n s i s t e n t f o r any one s p e c i e s . R e c e n t r e s e a r c h i n d i c a t e s h o w e v e r , t h a t t h i s a s s u m p t i o n may n o t be e n t i r e l y v a l i d . " O p t i m u m " n u t r i e n t l e v e l s i n t h e f o l i a g e o f a s p e c i e s h a v e b e e n shown t o c h a n g e w i t h p r o v e n a n c e ( v a n den D r i e s s c h e , 1 9 7 3 ) , age ( M i l l e r e t a l . , 1 9 8 1 ) , h e i g h t ( D i g h t o n and H a r r i s o n , 1983) and e v e n s i t e ( B o n n e a u , 1 9 7 3 ) . F o l i a r n u t r i e n t c o m p o s i t i o n s a r e t y p i c a l l y r e p o r t e d i n r e l a t i v e t e r m s s u c h a s c o n c e n t r a t i o n ( i . e . p e r c e n t a g e o r ppm o f o v e n d r y - w e i g h t ) ( L e a f , 1 9 7 3 ; v a n den D r i e s s c h e , 1 9 7 4 ) . When e x p r e s s e d i n s u c h t e r m s , f e r t i l i z e r t r e a t m e n t e f f e c t s , s u c h a s d i l u t i o n and a n t a g o n i s m , o f t e n become o b s c u r e d (T immer and S t o n e , 1 9 7 8 ) . The u s e o f c o n t e n t ( i . e . mg p e r f a s c i c l e , p e r 100 n e e d l e s o r p e r sq cm o f l e a f a r e a ) a s an e x p r e s s i o n o f f o l i a r n u t r i e n t l e v e l s h a s b e e n s u g g e s t e d a s an a l t e r n a t i v e ( L e a f , 1 9 7 3 ) . H o w e v e r , B r o c k l e y ( 1 9 8 1 ) s u g g e s t e d t h a t f r o m a n u t r i t i o n a l v i e w p o i n t , a b s o l u t e u p t a k e i s l e s s i m p o r t a n t t h a n c o n c e n t r a t i o n . I d e a l l y , a method w h i c h e x p r e s s e s n u t r i e n t c o m p o s i t i o n i n b o t h c o n c e n t r a t i o n and c o n t e n t w o u l d be s u p e r i o r t o u s i n g s i m p l y one o r t h e o t h e r . A g r a p h i c a l t e c h n i q u e , o r i g i n a l l y d e v e l o p e d by K r a u s s ( 1 9 6 7 ) , w h i c h e f f e c t i v e l y i n c o r p o r a t e s n e e d l e n u t r i e n t c o n c e n t r a t i o n , c o n t e n t and n e e d l e w e i g h t h a s b e e n u s e d by a number o f r e s e a r c h e r s ( H e i n s d o r f , 1 9 6 7 ; C z a p o w s k y j e t a l . , 1 9 8 0 ; T immer and S t o n e , 1 9 7 8 ; Weetman and F o u r n i e r , 1 9 8 3 ) . T h i s m e t h o d e n a b l e s r e s e a r c h e r s t o e f f e c t i v e l y d i s t i n g u i s h b e t w e e n t r e a t m e n t e f f e c t s (T immer and S t o n e , 1 9 7 8 ) . T h i s same a p p r o a c h h a s t h e r e f o r e b e e n u s e d i n t h i s s t u d y t o h e l p i n t e r p r e t f o l i a r a n a l y s i s and i n d i c a t e where p o t e n t i a l f u t u r e g r o w t h r e s p o n s e s may be e x p e c t e d . - 1 2 -In t h i s method t h e a b s o l u t e o r r e l a t i v e c h a n g e s i n n e e d l e n u t r i e n t c o n c e n t r a t i o n s , n e e d l e c o n t e n t , and n e e d l e w e i g h t , r e s u l t i n g f r o m a c t u a l f e r t i l i z e r t r i a l s , a r e g r a p h i c a l l y c o m p a r e d t o a c o n t r o l (Weetman and F o u r n i e r , 1 9 8 3 ) ( F i g u r e 2 ) . The i n t e r p r e t a t i o n s a s t o w h e t h e r a n u t r i e n t i s d e f i c i e n t and w h e t h e r a r e s p o n s e t o f e r t i l i z a t i o n c a n be e x p e c t e d a r e b a s e d on t h e d i r e c t i o n and m a g n i t u d e o f t h e s h i f t s f r o m t h e c o n t r o l ( F i g u r e 2 ) . Use o f t h i s t e c h n i q u e i s b a s e d on two a s s u m p t i o n s : ( i ) — d r y - w e i g h t o f n e e d l e s i s c l o s e l y c o r r e l a t e d w i t h f e r t i l i z e r g r o w t h r e s p o n s e s , and ( i i ) — n e e d l e number i s f i x e d i n t h e f i r s t s e a s o n f o l l o w i n g f e r t i l i z a t i o n (T immer and S t o n e , 1 9 7 8 ) . F o r most c o n i f e r s , t h i s l a t t e r a s s u m p t i o n i s met s i n c e t h e l e a f p r i m o r d i a a r e i n i t i a t e d and s e t i n t h e p r e v i o u s y e a r . T h i s h a s b e e n shown t o be t r u e f o r S i t k a s p r u c e ( C a n n e l and W i l l e t t , 1 9 7 5 ) , b u t s p e c i e s s u c h a s h e m l o c k and c e d a r do n o t h a v e t h i s c h a r a c t e r i s t i c and t h e r e f o r e t h e t e c h n i q u e may n o t be a s a p p l i c a b l e t o t h e m . Good c o r r e l a t i o n h a s e i t h e r b e e n f o u n d o r h a s b e e n s u g g e s t e d t o e x i s t b e t w e e n t h e w e i g h t o f n e e d l e s one y e a r a f t e r f e r t i l i z a t i o n and s u b s e q u e n t g r o w t h r e s p o n s e s ( L e y t o n , 1 9 5 6 ; Keay e t a l . , 1 9 6 8 ; Weetman and A l g a r , 1 9 7 4 ; T immer and S t o n e , 1 9 7 8 ; M o r r o w , 1 9 7 9 ) . Numerous o t h e r s t u d i e s , w h i l e n o t d i r e c t l y i n v e s t i g a t i n g t h e r e l a t i o n s h i p s o f n e e d l e w e i g h t , h a v e n o t e d a c o n n e c t i o n b e t w e e n c h a n g e s i n n e e d l e w e i g h t a n d s u b s e q u e n t g r o w t h r e s p o n s e s f o l l o w i n g f e r t i l i z a t i o n ( M a k i , 1 9 6 0 ; F e r d a , 1 9 7 5 ; H a i n e s e t a l . , 1 9 7 5 ; UNIT NEEDLE WEIGHT - 1 3 -(mg/NEEDLE) — > -ELEMENT CONTENT (ug/NEEDLE) DIRECTION OF SHIFT RESPONSE IN CHANGE IN . NEEDLE WEIGHT NUTRIENT NUTRIENT STATUS POSSIBLE DIAGNOSIS CONC. CON TIC NT A + + DILUTION NON-LIMITING B + 0 + UNCHANGED NON-LIMITING C + + + DEFICIENCY LIMITING D 0 + + LUXURY NON-TOXIC CONSUMPTION E - + + + EXCESS TOXIC F EXCESS ANTAGONISTIC Possible Diagnosis: 1. A shift towards A^  implies nutrient supply diluted by additional growth, suggesting nutrient may not be limiting. 2. A shift towards Js implies nutrient transport into foliage just sufficient to keep pace with shoot or leaf expansion, indicating nutrient may not be limiting. 3. A shift towards C implies the nutrient was limiting. 4 . A shift towards JJ implies luxury consumption by the foliage. 5. A shift towards JC implies a toxic effect of the nutrient unless associated with other growth constraints. 6. A shift towards F implies a deficiency induced by the treatment, true antagonism. FIGURE 2. S c h e m a t i c r e l a t i o n s h i p s between n e e d l e n u t r i e n t c o n c e n t r a t i o n , c o n t e n t and n e e d l e d r y - w e i g h t f o l l o w i n g f e r t i l i z a t i o n ( M o r r o w , 1 9 7 9 ) . -14-M c l n t o s h , 1982). S t i l l o t h e r f e r t i l i z a t i o n s t u d i e s have used a l t e r n a t i v e n e e d l e parameters such a s , needle a r e a , l e n g t h , and t o t a l biomass t o c h a r a c t e r i z e t r e a t m e n t r e s p o n s e s ( B r i x , 1971; Tamm, 1974; M i l l e r and M i l l e r , 1976; Turner and O l s o n , 1976). I n d i v i d u a l n e e d l e weight has been shown t o be h i g h l y c o r r e l a t e d w i t h n e e d l e l e n g t h (Timmer and Stone, 1978) and s u r f a c e a r e a (Gordon and Gatherum, 1967; M e l l o r and Tregunna, 1972; van den D r i e s s c h e , 1974) and, s i n c e n e e d l e weight i s e a s i e r t o d e t e r m i n e , i t tends t o be used more o f t e n (Morrow, 1979). Timmer and Stone (1978) argued t h a t s i n c e shoot growth i s d e t e r m i n a t e , d i f f e r e n c e s i n t o t a l w e i g h t of f i r s t year f o l i a g e / t r e e must c l o s e l y r e f l e c t d i f f e r e n c e s i n weight of i n d i v i d u a l n e e d l e s i n the f i r s t season a f t e r f e r t i l i z a t i o n . They f u r t h e r suggested t h a t t h i s s h o u l d then be r e l a t e d t o f u t u r e growth performance s i n c e i t has been shown t h a t the dominant mechanism u n d e r l y i n g growth r e s p o n s e s i s i n c r e a s e d p h o t o s y n t h e t i c a r e a (Tamm, 1974; Fagerstrom and Lohm, 1977). A s i m i l a r assumption was f i r s t a l l u d e d t o by L e y t o n ( 1 9 5 6 ) . He noted t h a t when a treatment had an e f f e c t on t r e e growth, the response was f i r s t r e f l e c t e d i n an i n c r e a s e i n n e e d l e w e i g h t . Keay et a l . (1968) suggested t h a t changes i n needle weight f o l l o w i n g f e r t i l i z a t i o n may p r o v i d e a r a p i d method of i d e n t i f y i n g p o t e n t i a l l y r e s p o n s i v e s t a n d s . The use of n e e d l e weight as a p r e d i c t o r of growth r e s p o n s e s i s not w i t h o u t problems however. Mahendrappa and S a l o n i u s (1982) found l i t t l e change i n b l a c k spruce ( P i c e a  mariana ( M i l l . ) BSP) n e e d l e weight a f t e r urea f e r t i l i z a t i o n - 1 5 -d e s p i t e a s i g n i f i c a n t g r o w t h r e s p o n s e . E v e r a r d ( 1 9 7 3 ) , w h i l e a c k n o w l e d g i n g t h a t n e e d l e w e i g h t i s a good i n d i c a t i o n o f t h e h e a l t h and v i g o u r o f a t r e e , s u g g e s t e d t h a t i t may n o t be a s w e l l c o r r e l a t e d t o g r o w t h a s n e e d l e n u t r i e n t c o n c e n t r a t i o n s . P a r t o f t h e p r o b l e m a s s o c i a t e d w i t h c o r r e l a t i n g g r o w t h r e s p o n s e s w i t h n e e d l e w e i g h t i n c r e a s e s l i e s i n t h e f a c t t h a t n e e d l e w e i g h t , l i k e n u t r i e n t c o n c e n t r a t i o n s , i s h i g h l y v a r i a b l e and s t r o n g l y i n f l u e n c e d by e n v i r o n m e n t a l f a c t o r s ( T u r n e r and O l s o n , 1 9 7 6 ) . G a r r e t t and Zahmer ( 1 9 7 3 ) n o t e d t h a t m o i s t u r e s t r e s s d u r i n g t h e g r o w i n g s e a s o n c o u l d s i g n i f i c a n t l y i n f l u e n c e t h e n u m b e r , s i z e , and p r e s u m a b l y w e i g h t , o f n e e d l e s i n t h e f o l l o w i n g g r o w i n g s e a s o n by i n f l u e n c i n g t h e number o f n e e d l e p r i m o r d i a i n i t i a t e d . S i m i l a r l y , P o l l a r d and L o g a n ( 1 9 7 7 ) f o u n d t h a t p h o t o p e r i o d and t e m p e r a t u r e had a s i g n i f i c a n t i n f l u e n c e on t h e n e e d l e p r i m o r d i a i n i t i a t e d i n P i c e a s p e c i e s . C o n n e l l and W i l l e t t ( 1 9 7 5 ) n o t e d t h a t s h o o t e x t e n s i o n i n d e t e r m i n a t e s p e c i e s s u c h a s S i t k a s p r u c e was l a r g e l y c o n t r o l l e d by t h e number o f n e e d l e p r i m o r d i a i n i t i a t e d i n t h e c u r r e n t y e a r r a t h e r t h a n t h e e l o n g a t i o n o f i n t e r n o d e s b e t w e e n p r i m o r d i a . T r e e s w i t h f e w e r n e e d l e s may t h e r e f o r e grow l e s s t h a n t r e e s w i t h more n e e d l e s d e s p i t e a g r e a t e r n e e d l e w e i g h t . M o r e o v e r , a t r e e w i t h f e w e r n e e d l e s i n t h e y e a r o f f e r t i l i z a t i o n may h a v e a r e l a t i v e l y l a r g e r i n c r e a s e i n n e e d l e w e i g h t t h a n a t r e e w i t h more n e e d l e s s i n c e g r o w t h w o u l d be c o n c e n t r a t e d on f e w e r n e e d l e s . T h u s i t i s a p p a r e n t t h a t some c a r e must be e x e r c i s e d i n i n t e r p r e t i n g c h a n g e s i n n e e d l e w e i g h t . T h i s w i l l be p a r t i c u l a r l y t r u e when c o m p a r i n g n e e d l e w e i g h t - 1 6 -r e s p o n s e s o f t r e e s f r o m s t a n d s o f w i d e l y d i f f e r i n g g e o g r a p h i c a n d / o r s i t e c h a r a c t e r i s t i c s . D e s p i t e some o f t h e p r o b l e m s a s s o c i a t e d w i t h u s i n g n e e d l e w e i g h t a s a g r o w t h p r e d i c t o r , t h e g r a p h i c a l t e c h n i q u e u s e d i n t h i s s t u d y h a s some a d v a n t a g e s o v e r t h e c r i t i c a l n u t r i e n t l e v e l c o n c e p t s i n c e i t a l l o w s f o r t h e i d e n t i f i c a t i o n o f t h e d i f f e r e n t t r e a t m e n t e f f e c t s . M o r e o v e r , n e e d l e w e i g h t a p p e a r s t o be a s e n s i t i v e i n d i c a t o r o f t h e g e n e r a l h e a l t h o f a t r e e ( E v e r a r d , 1 9 7 3 ) and t h e r e f o r e s h o u l d be r e l a t e d t o g r o w t h . T r e e s g r o w i n g on n u t r i e n t d e f i c i e n t s i t e s t y p i c a l l y show a g r a d u a l s h o r t e n i n g o f n e e d l e s and a d e c r e a s e i n n e e d l e w e i g h t . T h e s e same t r e e s o n c e f e r t i l i z e d u s u a l l y show an i n c r e a s e i n n e e d l e w e i g h t f o l l o w e d by a s u b s e q u e n t i n c r e a s e i n h e i g h t g r o w t h ( F e r d a , 1 9 7 5 ) . I t s h o u l d t h e r e f o r e be p o s s i b l e , b a s e d on c h a n g e s i n n e e d l e w e i g h t and n u t r i e n t c o m p o s i t i o n , t o i d e n t i f y p o t e n t i a l l y r e s p o n s i v e s t a n d s . S i t k a s p r u c e N u t r i t i o n and F e r t i l i z e r R e s p o n s e A l t h o u g h S i t k a s p r u c e i s r e c o g n i z e d a s an i m p o r t a n t t i m b e r and p u l p s p e c i e s i n t h e P a c i f i c N o r t h w e s t , l i t t l e a t t e n t i o n h a s b e e n g i v e n t o i t s n u t r i t i o n a l r e q u i r e m e n t s ( F a r r e t a l . , 1 9 7 7 ) . T h i s i s p r o b a b l y due t o t h e f a c t t h a t S i t k a s p r u c e was o f r e l a t i v e l y m i n o r i m p o r t a n c e f o r r e f o r e s t a t i o n ( R o c h e and F o w l e r , 1 9 7 5 ) , p a r t i c u l a r l y when c o m p a r e d w i t h o t h e r c o a s t a l s p e c i e s s u c h a s D o u g l a s - f i r ( P s e u d o t s u g a m e n z i e s i i ( M i r b . ) F r a n c o ) . T h i s h a s n o t b e e n t h e c a s e i n E u r o p e , e s p e c i a l l y i n B r i t a i n where S i t k a s p r u c e was o r i g i n a l l y i n t r o d u c e d a s an e x o t i c s p e c i e s i n 1831 ( R o c h e - 1 7 -and F o w l e r , 1 9 7 5 ) . I t s p o t e n t i a l f o r r a p i d g r o w t h and h i g h v o l u m e p r o d u c t i o n was r e c o g n i z e d q u i c k l y and s m a l l s c a l e p l a n t a t i o n s o f S i t k a s p r u c e were e s t a b l i s h e d a s e a r l y a s 1 8 6 6 , w i t h l a r g e r c o m m e r c i a l p l a n t a t i o n s b e i n g e s t a b l i s h e d by 1913 ( D a v i e s , 1 9 8 2 ) . S i n c e t h e n S i t k a s p r u c e p l a n t a t i o n s h a v e b e e n e s t a b l i s h e d on a l a r g e s c a l e i n B r i t a i n ( R o c h e and F o w l e r , 1975) and i t i s now t h e p r e d o m i n a n t s p e c i e s p l a n t e d ( D a v i e s , 1 9 8 2 ) . In 1 9 7 0 , t h e n a t i o n a l r e q u i r e m e n t f o r S i t k a s p r u c e s e e d i n B r i t a i n t o t a l l e d o v e r 1300 kg ( B u s z e w i c z , 1 9 7 0 ) , w h e r e a s i n B r i t i s h C o l u m b i a , i n 1 9 6 9 , t h e t o t a l s e e d r e q u i r e m e n t was o n l y 39 kg ( B . C . F o r . S e r v . , 1 9 6 9 ) . Much o f o u r k n o w l e d g e o f t h i s s p e c i e s ' n u t r i t i o n a l r e q u i r e m e n t s h a s t h e r e f o r e o r i g i n a t e d f r o m r e s e a r c h i n B r i t i s h f o r e s t s . N u t r i t i o n a l l y , S i t k a s p r u c e i s c o n s i d e r e d t o be a r e l a t i v e l y d e m a n d i n g s p e c i e s ( K r a j i n a e t a l . , 1 9 8 2 ) , h o w e v e r , i t s g e o g r a p h i c d i s t r i b u t i o n i s t h o u g h t t o be r e s t r i c t e d more by c l i m a t e and p h y s i o g r a p h y r a t h e r t h a n e d a p h i c f a c t o r s ( R o c h e and F o w l e r , 1 9 7 5 ) . In i t s n a t u r a l h a b i t a t , t h e s p e c i e s i s r e s t r i c t e d t o low e l e v a t i o n s o f t h e P a c i f i c c o a s t a l f o g b e l t . T h i s a r e a i s c h a r a c t e r i z e d by h a v i n g a p e r h u m i d c l i m a t e o f m o d e r a t e t e m p e r a t u r e and h i g h p r e c i p i t a t i o n . S i t k a s p r u c e h a s b e e n shown t o be a s t o l e r a n t t o h i g h w a t e r t a b l e s a s w e s t e r n r e d c e d a r ( M i n o r e , 1 9 7 0 ; K r a j i n a e t a l . , 1 9 8 2 ) . H o w e v e r , on s i t e s s u b j e c t e d t o f l o o d i n g , r o o t d e v e l o p m e n t i s r e s t r i c t e d t o t h e u p p e r h o r i z o n s ( C o r d e s , 1 9 7 2 ) . A l t h o u g h c a p a b l e o f p r o d u c i n g b o t h d e e p and s h a l l o w r o o t s y s t e m s ( B l y t h and M a c l e o d , 1 9 8 1 ; C o r d e s , 1 9 7 2 ) , b e s t - 1 8 -g r o w t h o c c u r s on d e e p , a c i d i c t o m i l d l y a c i d i c s o i l s w h i c h a l l o w f r e e r o o t i n g t o a d e p t h o f a t l e a s t 1 m ( R o c h e and F o w l e r , 1 9 7 5 ) . L a c k o f a d e q u a t e r o o t i n g v o l u m e i s c o n s i d e r e d t o be one o f t h e m a i n f a c t o r s l i m i t i n g p r o d u c t i v i t y on many s i t e s i n b o t h t h e P a c i f i c N o r t h w e s t and B r i t a i n ( D a y , 1 9 5 7 ; R o s s and M a l c o l m , 1 9 8 2 ) . A l t h o u g h S i t k a s p r u c e s e e d l i n g s c a n t o l e r a t e h i g h l e v e l s o f ammonium c o m p o u n d s , b e s t g r o w t h i s b e l i e v e d t o o c c u r when n i t r a t e s p r e d o m i n a t e ( K r a j i n a e t a l . , 1 9 8 2 ) . T a y l o r ( 1 9 3 5 ) a l s o n o t e d t h a t S i t k a s p r u c e r e g e n e r a t i o n i n A l a s k a was most a b u n d a n t and v i g o r o u s on s o i l s w i t h h i g h n i t r i f y i n g c a p a b i l i t i e s . T h e s e f i n d i n g s h o w e v e r , a r e i n c o n t r a s t w i t h t h o s e o f v a n den D r i e s s c h e ( 1 9 7 1 ) who f o u n d t h a t ammonium t e n d e d t o p r o d u c e b e t t e r g r o w t h t h a n n i t r a t e . S i m i l a r l y , e x t e n s i v e n u r s e r y r e s e a r c h i n B r i t a i n h a s f o u n d t h a t ammonium s u l p h a t e c o n s i s t e n t l y g a v e b e t t e r g r o w t h t h a n c a l c i u m n i t r a t e ( B e n z i a n , 1 9 6 5 ) . H o w e v e r , L e y t o n ( 1 9 5 2 ) f o u n d l i t t l e d i f f e r e n c e i n g r o w t h b e t w e e n ammonium- and n i t r a t e - f e d s e e d l i n g s . T h e r e i s s t i l l no c o n c e n s u s on t h e s p e c i e s ' p r e f e r e n c e o f N f o r m ( v a n den D r i e s s c h e and D a n g e r f i e l d , 1 9 7 5 ; Adams and A t w i l l , 1 9 8 2 ) . The a b i l i t y o f a t r e e t o u t i l i z e any one f o r m o f N d e p e n d s on f a c t o r s s u c h a s p H , l i g h t , m o i s t u r e , a g e , c a r b o h y d r a t e s u p p l y , and n i t r a t e r e d u c t a s e a c t i v i t y ( M i c h a e l e t a l . , 1 9 7 0 ; B e e v e r s and H a g e m a n , 1 9 6 9 ; B i g g and D a n i e l , 1 9 7 8 ) . A l t h o u g h i t h a s b e e n shown t h a t p l a n t s v a r y i n t h e i r c a p a b i l i t i e s t o grow on ammonium and n i t r a t e ( B e e v e r s and H a g e m a n , 1 9 8 3 ) , i t seems u n l i k e l y t h a t a t r e e , i n i t s n a t u r a l e n v i r o n m e n t , w o u l d - 1 9 -a c t i v e l y p r e f e r one f o r m o f N o v e r t h e o t h e r . In f a c t , n u m e r o u s f e r t i l i z e r t r i a l s h a v e shown t h a t s i g n i f i c a n t l y g r e a t e r r e s p o n s e s c a n o f t e n be o b t a i n e d when b o t h f o r m s o f N a r e a d d e d s i m u l t a n e o u s l y ( B i n n s , 1 9 7 5 ; B e e v e r s and H a g e m a n , 1 9 8 3 ) . T h e r e h a v e b e e n n u m e r o u s a t t e m p t s t o q u a n t i f y f o l i a r n u t r i e n t l e v e l s a s s o c i a t e d w i t h good and p o o r g r o w t h o f S i t k a s p r u c e ( T a b l e 1 ) . In g e n e r a l , i t c a n be s a i d t h a t p o o r g r o w t h o f S i t k a s p r u c e o c c u r s when f o l i a r n u t r i e n t l e v e l s a r e l e s s t h a n 1 . 2 % , 0 . 1 4 % , and 0 . 5 % f o r N, P and K r e s p e c t i v e l y , w h e r e a s good g r o w t h i s a s s o c i a t e d w i t h l e v e l s g r e a t e r t h a n 1 .5% N, 0 . 1 8 % P , and 0 . 8 % K. V a l u e s i n b e t w e e n t h e s e l i m i t s a r e d e s c r i b e d a s b e i n g m a r g i n a l , and a l t h o u g h g r o w t h r e s p o n s e s t o f e r t i l i z a t i o n c a n be e x p e c t e d i n t h i s r a n g e , t h e r e s p o n s e s a r e o f t e n s m a l l ( E v e r a r d , 1 9 7 3 ) . N u t r i e n t d e f i c i e n c i e s s e v e r e e n o u g h t o s i g n i f i c a n t l y i n f l u e n c e g r o w t h o f S i t k a s p r u c e p l a n t a t i o n s i n B r i t a i n h a v e commonly b e e n r e c o r d e d f o r N, P , K, and o c c a s i o n a l l y Cu ( B i n n s e t a l . , 1 9 8 0 ) . C o u n t l e s s n u m b e r s o f f e r t i l i z e r t r i a l s h a v e shown t h e s p e c i e s t o be h i g h l y r e s p o n s i v e t o r e m e d i a l f e r t i l i z a t i o n when t h e s e d e f i c i e n c i e s e x i s t ( D i c k s o n , 1 9 7 3 ; C h a r l i s l e and B r o w n , 1 9 7 3 ; D i c k s o n and S a v i l l , 1 9 7 4 ; M c i n t o s h , 1 9 7 8 , 1 9 8 1 , 1 9 8 3 ) . S i m i l a r l y , i n t h e P a c i f i c N o r t h w e s t , S i t k a s p r u c e p l a n t a t i o n s and s e c o n d g r o w t h s t a n d s h a v e b e e n shown t o be h i g h l y r e s p o n s i v e t o n i t r o g e n o u s f e r t i l i z e r s , o f t e n more so t h a n o t h e r s p e c i e s s u c h a s h e m l o c k o r D o u g l a s - f i r ( A u s t i n and S t r a n d , 1 9 6 0 ; W e b s t e r e t a l . , 1 9 7 6 ; F a r r e t a l . , 1 9 7 7 ) . TABLE 1. Fbliar nutrient concentrations assolciated with good and poor growth of Sitka spruce, western hemlock and western red cedar. SPECIES PERCENT OVEN-DRY WEIGHT Ca Mg Sitka spruce Good growth - mean' 1.47 0.24 1.15 0.24 0.12 - range (1. 07-1.76) (0.18-0.33) (0. 68-1.58) (0. 15-0. 40) (0. 09-0.16) 2 - mean 1.38 0.22 0.80 0.31 0.09 - range (1. 05-1.66) (0.13-0.32) (0. 55-1.35) (0. 13-0. 56) (0. 06-0.15) Optimum-3 >1.50 >0.18 >0.70 - >0.07 Poor growth - mean' 0.95 0.16 0.69 0.28 0.10 - range (0. 72-1.27) (0.08-0.19) (0. ,30-0.89) (0. ,21-0. 37) '(0. 08-0.12) 2 - mean-1- 0.88 0.15 0.65 0.31 0.07 - range (0. ,69-1.12) (0.10-0.21) (0, .42-0.92) (0. ,14-0. ,50) (0, ,03-0.10) Deficient''' <1.20 <0.14 <0.50 - <0.07 Western hemlock Good growth - mean-^  1.28 0.28 0.68 0.20 0.13 - range (1 .00-1.48) (0.18-0.34) (0 .26-0.94) (0 .09-0, .34) (0 .09-0.17) Optimum-3 >1.50 >0.30 >0.80 - -Poor growth 2 - mean'- 0.83 0.18 0.62 0.17 0.09 - range (0 .60-1.02) (0.09-0.40) (0 .40-0.82) (0 .08-0 .28) (0 .07-0.14) Deficient" 3 <1.20 <0.25 <0.60 - -Western red cedar Deficient'^ 1.50 0.13 0 .40-0.80 0 .10-0 .20 0 .06-0.12 Sources: 1. Binns and Atterson, 1967, 2. Farr et a l . , 1977. 3 . Binns et a l . , 1980. 4. Ballard, 1982. I O I - 2 1 -W e b s t e r e t a l . ( 1 9 7 6 ) n o t e d t h a t h e m l o c k - s p r u c e s t a n d s i n O r e g o n f e r t i l i z e d w i t h 168 and 336 kg N/ha had a v e r a g e d i a m e t e r r e s p o n s e s 4 t o 6 y e a r s a f t e r f e r t i l i z a t i o n o f 27% and 4 9 % , r e s p e c t i v e l y f o r s p r u c e , b u t o n l y 3% and 18%, r e s p e c t i v e l y f o r h e m l o c k . F a r r e t a l . ( 1 9 7 7 ) f o u n d t h a t t h e a d d i t i o n o f 448 k g / h a o f u r e a t o S i t k a s p r u c e p l a n t a t i o n s i n A l a s k a r e s u l t e d i n an a v e r a g e 20 t o 25% i n c r e a s e i n h e i g h t g r o w t h o v e r a 3 t o 4 y e a r p e r i o d . F e r t i l i z e r t r i a l s f r o m B r i t a i n h a v e shown t h a t S i t k a s p r u c e i s p a r t i c u l a r l y r e s p o n s i v e t o p h o s p h o r u s f e r t i l i z a t i o n . W h i l e t h e most r e s p o n s i v e s i t e s h a v e b e e n f r o m s i t e s w i t h deep o r g a n i c s o i l s , p a r t i c u l a r l y t h e o l i g o t r o p h i c p e a t s , P d e f i c i e n c i e s i n s p r u c e o r r e s p o n s e s t o P f e r t i l i z a t i o n h a v e b e e n known t o o c c u r on a r a n g e o f d i f f e r e n t s i t e s ( M c i n t o s h , 1 9 8 1 ) . I t i s now r e c o g n i z e d t h a t s a t i s f a c t o r y g r o w t h o f S i t k a s p r u c e on o r g a n i c s o i l s i s v i r t u a l l y i m p o s s i b l e u n l e s s a t o p d r e s s i n g o f P o r P p l u s K i s a p p l i e d a t t h e t i m e o f p l a n t i n g ( M c i n t o s h , 1 9 8 3 ) . I n t h e P a c i f i c N o r t h w e s t , l i t t l e a t t e n t i o n h a s b e e n g i v e n t o P f e r t i l i z a t i o n a s i t i s g e n e r a l l y b e l i e v e d t h a t n i t r o g e n i s t h e most l i m i t i n g e l e m e n t i n s o i l s o f t h i s r e g i o n ( A t k i n s o n , 1 9 7 5 ) . H o w e v e r , a number o f g r e e n h o u s e and p o t . t r i a l s u s i n g s o i l s f r o m a v a r i e t y o f c o a s t a l s i t e s h a v e shown s i g n i f i c a n t g r o w t h r e s p o n s e s o f S i t k a s p r u c e , h e m l o c k , and D o u g l a s - f i r s e e d l i n g s t o P and N p l u s P f e r t i l i z a t i o n ( M e u r i s s e , 1 9 7 6 ; H e i l m a n and E k u a n , 1 9 8 0 ; A n d e r s o n e t a l . , 1 9 8 2 ) . G e s s e l e t a l . ( 1 9 7 9 ) a l s o n o t e d t h a t i n many f e r t i l i z e r t r i a l s w i t h i n t h e P a c i f i c N o r t h w e s t where o t h e r - 2 2 -n u t r i e n t s b e s i d e s N have been t e s t e d , N p l u s P o f t e n gave b e t t e r r e s p o n s e s t h a n s i m p l y N a l o n e . I n g e n e r a l , b e n e f i t s f r o m P o r P p l u s K f e r t i l i z a t i o n on o r g a n i c s o i l s i n B r i t a i n have been f o u n d t o l a s t 7 t o 10 y e a r s ( M c i n t o s h , 1 9 8 1 ) . C o n s i d e r a b l y l o n g e r b e n e f i t s f r o m P f e r t i l i z a t i o n , o f t e n e x c e e d i n g 20 y e a r s , have o c c u r r e d on some s i t e s i n New Z e a l a n d ( B a l l a r d , R., 1978) and on a v a r i e t y o f s i t e s i n t h e s o u t h e a s t e r n S t a t e s ( P r i t c h e t t and C o m e r f o r d , 1 9 8 2 ) . The need f o r K f e r t i l i z a t i o n has been shown t o v a r y by s i t e , b u t i t i s g e n e r a l l y b e l i e v e d t h a t w i d e s p r e a d K d e f i c i e n c i e s w i l l o c c u r on most deep o r g a n i c s o i l s and t h a t many p l a n t a t i o n s e s t a b l i s h e d on t h e s e s i t e s w i l l r e q u i r e K f e r t i l i z a t i o n a t some t i m e i n t h e i r d e v e l o p m e n t ( A t t e r s o n and B i n n s , 1 9 7 5 ) . M c i n t o s h ( 1 9 8 1 ) n o t e d t h a t t h e p r o b a b i l i t y o f a K d e f i c i e n c y o c c u r r i n g i n c r e a s e d w i t h i n c r e a s i n g p e a t d e p t h . He s u g g e s t e d t h a t t h e r e seemed t o be a t h r e s h o l d v a l u e o f a b o u t 30 cm, a b o v e w h i c h a K d e f i c i e n c y i s u n l i k e l y , and b e l o w w h i c h a K d e f i c i e n c y i s h i g h l y l i k e l y . R e s p o n s e s t o K a p p e a r l e s s c o n s i s t e n t and d r a m a t i c t h a n r e s p o n s e s t o P. However, a number o f f e r t i l i z e r t r i a l s h ave shown t h a t i t i s p o s s i b l e t o g a i n s i g n i f i c a n t a d d i t i o n a l - b e n e f i t s by a d d i n g b o t h P and K a t t h e t i m e o f p l a n t i n g r a t h e r t h a n s i m p l y a d d i n g P a l o n e ( M c i n t o s h , 1 9 8 1 ) . The i n c l u s i o n o f N a t t h i s t i m e h a s n o t been e f f e c t i v e ( D i c k s o n and S a v i l l , 1 9 7 4 ) . A c t u a l g r o w t h r e s p o n s e s t o P p l u s K f e r t i l i z a t i o n i n B r i t a i n h ave been v e r y d r a m a t i c . D i c k s o n - 2 3 -and S a v i l l ( 1 9 7 4 ) f o u n d t h a t s e v e n y e a r s a f t e r P p l u s K f e r t i l i z a t i o n , i n c r e a s e s i n t o t a l h e i g h t g r o w t h o f S i t k a s p r u c e r a n g e d f r o m 128% t o 265% f o r P a p p l i c a t i o n s r a n g i n g f r o m 36 t o 216 kg P/ha. L e a d e r g r o w t h a t t h e end o f t h i s t i m e was s t i l l 100 t o 250% g r e a t e r t h a n t h e c o n t r o l s . B a s e d on a s u r v e y o f t h e B r i t i s h l i t e r a t u r e , t h e s e v a l u e s a p p e a r t o be t h e norm r a t h e r t h a n t h e e x c e p t i o n . I n many o f t h e s p r u c e p l a n t a t i o n s e s t a b l i s h e d i n B r i t a i n , s i g n s o f N d e f i c i e n c y o f t e n b e g i n t o a p p e a r 6 t o 8 y e a r s a f t e r p l a n t i n g ( D i c k s o n and S a v i l l , 1 9 7 4 ) . T h e s e p l a n t a t i o n s have been shown t o be h i g h l y r e s p o n s i v e t o N f e r t i l i z a t i o n . As m e n t i o n e d p r e v i o u s l y , S i t k a s p r u c e h a s a l s o been shown t o be h i g h l y r e s p o n s i v e t o n i t r o g e n o u s f e r t i l i z e r s i n t h e P a c i f i c N o r t h w e s t . U n l i k e t h e c a s e f o r P, r e s p o n s e s t o N a r e t y p i c a l l y o f s h o r t d u r a t i o n , o f t e n l a s t i n g o n l y 3 t o 4 y e a r s ( M c i n t o s h , 1981; F a r r e t a l . , 1 9 7 7 ) . However, t h e r e a r e numerous e x a m p l e s where c o n s i d e r a b l y l o n g e r r e s p o n s e s t o N f e r t i l i z a t i o n have been o b t a i n e d ( A t k i n s o n , 1 9 7 5 ) . M i l l e r ( 1 9 8 1 ) showed t h a t t h e l o n g e v i t y o f r e s p o n s e t o N f e r t i l i z a t i o n was r e l a t e d t o l u x u r y c o n s u m p t i o n ; i . e . t h e g r e a t e r t h e N u p t a k e o v e r and above t h e t r e e s i m m e d i a t e r e q u i r e m e n t s , t h e l o n g e r t h e r e s p o n s e . The s h o r t - t e r m n a t u r e o f N f e r t i l i z e r r e s p o n s e s has l e d i n v e s t i g a t o r s t o l o o k f o r a l t e r n a t i v e methods o f i m p r o v i n g t h e N n u t r i t i o n o f S i t k a s p r u c e . I n B r i t a i n t h i s h as p r i m a r i l y been a c h i e v e d t h r o u g h weed c o n t r o l a n d / o r c u l t i v a t i o n . B o t h methods have been shown t o be e f f e c t i v e i n - 2 4 -i m p r o v i n g t h e N n u t r i t i o n o f S i t k a s p r u c e p l a n t a t i o n s ( D i c k s o n a n d S a v i l l , 1 9 7 4 ; R o s s a n d M a l c o l m , 1 9 8 2 ) . D i c k s o n a n d S a v i l l ( 1 9 7 4 ) n o t e d h o w e v e r , t h a t r e g a r d l e s s o f t y p e a n d t i m e o f t r e a t m e n t , o n t h e p o o r e s t s i t e s , g r o w t h o f S i t k a s p r u c e w i l l b e c o m e l i m i t e d b y a N d e f i c i e n c y . R o s s a n d M a l c o l m ( 1 9 8 2 ) n o t e d t h a t t h e b e n e f i t s o f i n t e n s i v e s i t e p r e p a r a t i o n may o n l y l a s t f o r 1 0 t o 1 5 y e a r s . M o r e o v e r , w e e d c o n t r o l o r c u l t i v a t i o n a p p e a r t o m a i n l y b e n e f i t t h e N n u t r i t i o n o f t h e t r e e a n d n o t s o m u c h t h e P a n d K n u t r i t i o n . T h u s , f e r t i l i z a t i o n w i t h P p l u s K i s s t i l l r e q u i r e d i f s a t i s f a c t o r y g r o w t h i s t o b e a c h i e v e d . A l t h o u g h S i t k a s p r u c e h a s b e e n p l a n t e d i n B r i t a i n i n p u r e s t a n d s f o l l o w i n g f e r t i l i z a t i o n o n C a l l u n a m o o r l a n d s o i l s , r e c e n t a n a l y s i s o f m i x e d s t a n d s h a v e s h o w n i m p r o v e d g r o w t h r a t e s a n d P n u t r i t i o n o f S i t k a s p r u c e w h e n a s s o c i a t e d w i t h l o d g e p o l e p i n e . T h e r e a s o n s f o r t h i s i m p r o v e d P n u t r i t i o n a r e b e l i e v e d t o b e d u e t o c h a n g e s i n t h e m y c o r r h i z a l i n f e c t i o n o f t h e s p r u c e . S i m i l a r l y , C a l l u n a r o o t s a r e s u s p e c t e d o f u p s e t t i n g S i t k a s p r u c e P n u t r i t i o n v i a s o m e u n k n o w n m y c o r r h i z a l p r o c e s s . C a l l u n a e r a d i c a t i o n r e s u l t s i n i m p r o v e d P n u t r i t i o n . A p a r a l l e l b e t w e e n t h i s e f f e c t o f C a l l u n a a n d t h e r e d u c e d g r o w t h o f S i t k a s p r u c e o n s i t e s d o m i n a t e d b y s a l a l ( G a u t h e r i a s h a l l o n P u r s h . ) i n B . C . i s s u s p e c t e d ( W e e t m a n , F a c u l t y o f F o r e s t r y , U n i v e r s i t y o f B r i t i s h C o l u m b i a , p e r s o n a l c o m m u n i c a t i o n s ) . - 2 5 -S T U D Y A R E A AND S I T E D E S C R I P T I O N L o c a t i o n F i v e S i t k a s p r u c e p l a n t a t i o n s , l o c a t e d n e a r P o r t M c N e i l l o n n o r t h e r n V a n c o u v e r I s l a n d ( F i g u r e 3 ) , a n d r a n g i n g i n a g e f r o m 8 t o 1 4 y e a r s , w e r e s e l e c t e d f o r t h e f e r t i l i z e r t r i a l s . A l l p l a n t a t i o n s a r e l o c a t e d i n B l o c k 4 o f T r e e F a r m L i c e n c e 2 5 w h i c h i s p r e s e n t l y u n d e r t h e m a n a g e m e n t o f W e s t e r n F o r e s t P r o d u c t s L t d . A l l p l a n t a t i o n s a r e e s t a b l i s h e d o n t h e C e d a r - H e m l o c k p h a s e o f t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n a n d a r e e x h i b i t i n g s e v e r e c h l o r o s i s a n d g r o w t h c h e c k . C l i m a t e T h e r e g i o n h a s a C f b c l i m a t e ( a f t e r K o p p e n ' s c l a s s i f i c a t i o n : L e w i s , 1 9 8 2 ) . T h u s i t i s c h a r a c t e r i z e d b y h a v i n g m i l d w i n t e r s , c o o l m o i s t s u m m e r s a n d a r e l a t i v e l y l o n g s p r i n g a n d a u t u m n . T a b l e 2 g i v e s t h e 3 0 - y e a r n o r m a l v a l u e s o f t e m p e r a t u r e a n d p r e c i p i t a t i o n a s s u m m a r i z e d b y L e w i s ( 1 9 8 2 ) , a s w e l l a s t h e c l i m a t i c m e a n s f o r t h e 1 9 8 3 g r o w i n g s e a s o n . A l l d a t a w e r e o b t a i n e d f r o m t h e P o r t H a r d y A i r p o r t w e a t h e r s t a t i o n , l o c a t e d a b o u t 1 5 km n o r t h w e s t o f t h e p l a n t a t i o n s ( F i g u r e 3 ) . T h e m e a n d a i l y m a x i m u m t e m p e r a t u r e d u r i n g t h e w a r m e s t m o n t h s o f t h e y e a r ( J u l y a n d A u g u s t ) o n l y a v e r a g e s s l i g h t l y a b o v e 1 7 ° C a n d t h e m e a n d a i l y m i n i m u m t e m p e r a t u r e FIGURE 3. L o c a t i o n of study area. TA3LE 2. Temperature and precipitation values for Port Hardy. MONTHS MEAN DAILY MEAN DAILY MEAN DAILY MEAN MEAN MEAN TEMP. (oC) MAX. TEMP. (oC) MIN. TEMP. (oC) RAINFALL (mm) SNOWFALL (mm) PRECIPITATION (mm) 30 YEAR 1983 30 YEAR 1983 30 YEAR 1983 30 YEAR 1983 30 YEAR 1983 30 YEAR 1983 NORM NORM NORM NORM NORM NORM January 2.4 5.6 4.7 7.9 0.0 3.2 181 273 284 Trace 209 273 February 3.4 6.0 6.6 8.9 1.1 3.0 144 216 132 - 157 216 March 4.4 6.5 7.7 10.7 1.1 2.3 123 153 91 - 133 153 April 6.5 7.8 10.3 12.4 2.7 3.2 108 68 13 Trace 109 68 May 9.5 11.2 13.7 15.6 5.4 6.7 63 35 Trace - 63 35 June 11.0 12.4 15.8 15.3 8.3 9.4 59 163 0 - 59 163 July 13.6 14.0 17.3 17.5 9.9 10.4 54 151 0 - 54 151 August 13.3 14.0 17.3 18.1 10.2 10.4 68 56 0 - 68 56 Septembe 11.9 11.3 15.4 15.1 8.4 7.5 132 119 0 - 132 119 October 8.7 8.0 11.3. 11.4 5.6 4.6 253 170 0 Trace 253 170 November 5.3 6.3 7.8 8.7 2.8 3.9 231 288 33 33 234 291 December 4.5 1.1 5.7 4.0 1.2 -1.9 242 120 152 6 258 123 ANNUAL 8.0 8.7 11.2 12.1 4.7 5.2 1649 1812 706 6 1730 1818 •Note - Normal, mean values of temperature and precipitation for Port Hardy are projected from 25 - 29 years of record during the period 1941 - 1970 (Lewis, 1982)'. 1983 - Data frora Environment Canada's Weather Record for Port Hardy. -28-d u r i n g the c o l d e s t month ( J a n u a r y ) o n l y drops t o 0°C. The mean a n n u a l p r e c i p i t a t i o n i s about 1700 mm and o c c u r s m o s t l y as r a i n . A l t h o u g h May th r o u g h August tends t o be the d r i e s t p e r i o d of the y e a r , mean monthly p r e c i p i t a t i o n r a r e l y drops below 50 mm and thus s o i l m o i s t u r e d e f i c i t s a r e r a r e . However, due t o heavy r a i n f a l l , many s i t e s may s u f f e r from e x c e s s i v e m o i s t u r e l e v e l s e i t h e r y e a r - r o u n d or d u r i n g p a r t of the y e a r . For 1983, p r e c i p i t a t i o n i n A p r i l and May was c o n s i d e r a b l y l ower than the 30 — year a v e r a g e . T h i s was i m p o r t a n t s i n c e the f e r t i l i z e r was a p p l i e d i n the l a s t 2 t o 3 weeks of A p r i l , and thus the chance of l e a c h i n g , p a r t i c u l a r l y of the n i t r a t e i o n , would p r o b a b l y be l e s s than i n a "normal y e a r " . S i t e and Ecosystem D e s c r i p t i o n B l o c k 4 of T.F.L. 25 encompasses p a r t s of two major p h y s i o g r a p h i c s u b d i v i s i o n s — t h e Vancouver I s l a n d ranges and the N a w h i t t i Lowlands, w i t h the l a t t e r b e i n g f u r t h e r s u b d i v i d e d t o account f o r a l o w - l y i n g a r e a known as the Suquash B a s i n ( H o l l a n d , 1976). A l l f i v e p l a n t a t i o n s i n t h i s study a r e l o c a t e d w i t h i n t h i s b a s i n . I t i s c h a r a c t e r i z e d by h a v i n g a g e n t l y u n d u l a t i n g topography which seldom exceeds :300 m i n e l e v a t i o n . The s u r f a c e m a t e r i a l of the Suquash B a s i n m a i n l y c o n s i s t s of ve r y deep, u n c o n s o l i d a t e d , m o r a i n a l g l a c i a l and g l a c i a l f l u v i a l outwash m a t e r i a l . Lewis (1982) r e c e n t l y completed the e c o s y s t e m a t i c c l a s s i f i c a t i o n of B l o c k 4 of T.F.L. 25. H i s c l a s s i f i c a t i o n approach c l o s e l y f o l l o w s the b i o g e o c l i m a t i c ecosystem - 2 9 -c l a s s i f i c a t i o n p r e s e n t l y u s e d by t h e B r i t i s h C o l u m b i a M i n i s t r y o f F o r e s t s . W i t h i n B l o c k 4 , t h e most p r o m i n e n t s u b z o n e i s t h e W e t t e r N o r t h e r n M a r i t i m e C o a s t a l W e s t e r n H e m l o c k S u b z o n e (CWHe) o c c u p y i n g a p p r o x i m a t e l y 98 p e r c e n t o f t h e p r o d u c t i v e l a n d b a s e ( 3 0 , 5 2 9 h a ) . T h i s s u b z o n e i s f u r t h e r s u b d i v i d e d i n t o two v a r i a n t s , a l o w e r e l e v a t i o n s u b m o n t a n e v a r i a n t and a h i g h e r e l e v a t i o n montane v a r i a n t . The s u b m o n t a n e v a r i a n t e n c o m p a s s e s a b o u t 91 p e r c e n t o f t h e l a n d a r e a i n t h e CWHe s u b z o n e . L e w i s i d e n t i f i e d e l e v e n e c o s y s t e m a s s o c i a t i o n s i n t h i s v a r i a n t o f w h i c h t h e z o n a l o r " c l i m a t i c " e c o s y s t e m i s t h e T h u j a p l i c a t a - T s u g a  h e t e r o p h y l l a - A b i e s a m a b i l i s - G a u t h e r i a s h a l l o n -R h y t i d i a d e l p h u s l o r e u s ( r e f e r r e d t o h e r e i n a f t e r a s t h e S I o r s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n ) . The S I e c o s y s t e m a s s o c i a t i o n i s t h e d o m i n a n t e c o s y s t e m a s s o c i a t i o n w i t h i n B l o c k 4 and o c c u p i e s some 60 p e r c e n t o f t h e p r o d u c t i v e l a n d b a s e i n t h e CWHe s u b z o n e ( L e w i s , 1 9 8 2 ) . I t i s a l s o t h o u g h t t o o c c u p y a s i g n i f i c a n t p o r t i o n o f t h e r e m a i n i n g a r e a o f t h e p r o d u c t i v e l a n d b a s e o f n o r t h e r n V a n c o u v e r I s l a n d and may e v e n e x t e n d a s f a r s o u t h a l o n g t h e w e s t c o a s t o f V a n c o u v e r I s l a n d a s T o f i n o ( D u m o n t , W e s t e r n F o r e s t P r o d u c t s L t d . , p e r s o n a l c o m m u n i c a t i o n ) . A c c o r d i n g t o L e w i s ( 1 9 8 2 ) , t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n i s c o m p r i s e d o f two d i s t i n c t p h a s e s — t h e h e m l o c k -a m a b i l i s f i r ( H A - ) p h a s e and t h e c e d a r - h e m l o c k ( C H - ) p h a s e . T h e s e p h a s e s h a v e a p p a r e n t l y d e v e l o p e d due t o d i f f e r e n c e s i n s t a n d h i s t o r i e s . - 3 0 -T h e C H - p h a s e i s t h e c l i m a t i c c l i m a x c o m m u n i t y o f t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n . T h e m a t u r e s t a n d s o n t h e s e s i t e s c a n b e d e s c r i b e d a s b e i n g r e l a t i v e l y o p e n , c o n t a i n i n g l a r g e d e c a d e n t o l d - g r o w t h w e s t e r n r e d c e d a r ( T h u j a  p l i c a t a D o n n ) a n d h e m l o c k w i t h a m i n o r c o m p o n e n t o f a m a b i l i s f i r ( A b i e s a m a b i l i s ( D o u g l . ) F o r b e s ) ( F i g u r e A ) . T h e u n d e r s t o r y u s u a l l y c o n s i s t s o f a v e r y d e n s e , t a l l s h r u b l a y e r , i n v a r i a b l y d o m i n a t e d b y s a l a l . T h e h e r b l a y e r t e n d s t o b e s p a r s e w i t h t h e d o m i n a n t h e r b b e i n g B l e c h n u m s p i c a n t ( L . ) R o t h . T h e d o m i n a n t m o s s e s f o u n d i n t h i s p h a s e a r e H y l o c o m i u m s p l e n d e n s ( H e d w . ) B . S . G . a n d R h y t i d i a d e l p h u s l o r e u s ( H e d w . ) W a r n s t . T h e s e s t a n d s h a v e d e v e l o p e d o v e r a n u m b e r o f c e n t u r i e s w i t h l i t t l e o r n o d i s t u r b a n c e . D e s p i t e t h e i r a p p e a r a n c e , t h e y a r e c o n s i d e r e d t o b e h i g h l y v a l u a b l e a n d a v e r a g e y i e l d s , p r e d o m i n a n t l y d u e t o w e s t e r n r e d c e d a r , t y p i c a l l y e x c e e d 7 0 0 c u m / h a . T h e H A - p h a s e i s c h a r a c t e r i z e d b y d e n s e , e v e n - a g e d s t a n d s o f h e m l o c k a n d a m a b i l i s ( F i g u r e 4 ) . T h e f o r e s t f l o o r i s d o m i n a t d b y a c o n t i n u o u s c o v e r o f m o s s e s , m a i n l y S t o k e s i e l l a o r e g a n a ( S u l l . ) R o b i n s , a n d H y l o c o m i u m s p l e n d e n s . A l t h o u g h t h e h e r b l a y e r i s n o t w e l l - d e v e l o p e d , i t t e n d s t o b e m o r e v a r i e d t h a n i n t h e C H - p h a s e , a n d i n c l u d e s s u c h s p e c i e s a s B l e c h n u m s p i c a n t , P o l y s t i c h u m m u n i t u m ( K a u l f . ) P r e s l . a n d T i a r e l l a t r i f o l i a t a L . T h e s h r u b l a y e r , u n l i k e t h a t i n t h e C H - p h a s e , t e n d s t o b e s p a r s e w i t h o n l y a s p o r a d i c c o v e r o f s a l a l a n d V a c c i n i u m s p e c i e s . A c c o r d i n g t o L e w i s t h e s e s t a n d s a r e s e r a i , a n d i f a l l o w e d t o d e v e l o p w i t h o u t d i s t u r b a n c e , w i l l e v e n t u a l l y - 3 1 -? F I G U R E 4 . M a t u r e s t a n d s o f t h e H A - a n d C H - p h a s e s . a ) I I A - p h a s e - - t h i s s t a n d i s a p p r o x i m a t e l y 7 0 y e a r s o l d a n d o r i g i n a t e d f r o m a 1 9 0 6 b l o w d o w n . 9 • • b ) C H - p h a s e - - t h i s s t a n d i s u n e v e n a g e d ( 1 4 0 - 3 0 0 + y e a r s ) a n d h a s d e v e l o p e d w i t h l i t t l e o r n o d i s t u r b a n c e . - 3 2 -r e v e r t t o t h e C H - p h a s e . A p p a r e n t l y , t h e H A - p h a s e d e v e l o p s a s a r e s u l t o f e x t e n s i v e w i n d t h r o w d i s t u r b a n c e s , t h e l a t e s t o f w h i c h r e s u l t e d f r o m a s e v e r e s t o r m i n 1 9 0 6 . S i m i l a r d e n s e s t a n d s o f S i t k a s p r u c e a n d h e m l o c k a n d o f h e m l o c k a n d a m a b i l i s h a v e d e v e l o p e d d u e t o e x t e n s i v e w i n d t h r o w i n t h e E s t e v a n a n d W e s t V a n c o u v e r I s l a n d W e t t e r M a r i t i m e B i o g e o c l i m a t i c s u b z o n e s ( K l i n k a e t a l . , 1 9 7 9 ) . S i n c e r e m a i n s o f t h e o r i g i n a l o l d - g r o w t h s t a n d s , p a r t i c u l a r l y t h e r e d c e d a r c o m p o n e n t , a r e n o t r e a d i l y e v i d e n t i n m a n y o f t h e s t a n d s o f t h e H A - p h a s e , i t i s u n l i k e l y t h a t t h e s e s t a n d s d e v e l o p e d f r o m a s i n g l e w i n d t h r o w d i s t u r b a n c e , b u t r a t h e r , w e r e p r o b a b l y s u b j e c t e d t o a s e r i e s o f p e r i o d i c d i s t u r b a n c e s . T h i s w a s h i g h l i g h t e d r e c e n t l y i n 1 9 8 2 , w h e n m o r e t h a n 4 0 0 h a o f t h e s e s t a n d s h a d t o b e s a l v a g e d d u e t o s e v e r e b l o w d o w n ( C o a s t a l S i l v i c u l t u r a l C o m m i t t e e 2 ( C S C ) W o r k s h o p , 1 9 8 3 ) . S u c h d r a m a t i c d i s t u r b a n c e s w o u l d p r o v i d e l a r g e a r e a s o f m i x e d m i n e r a l s o i l / o r g a n i c m a t t e r s e e d b e d s . A f t e r d i s t u r b a n c e , e x t r e m e l y d e n s e a n d v i g o r o u s h e m l o c k a n d a m a b i l i s n a t u r a l r e g e n e r a t i o n d e v e l o p s o n t h e s e s i t e s . D e n s i t y e s t i m a t e s o f 1 0 , 0 0 0 t o 2 0 , 0 0 0 s t e m s / h a o r m o r e a p p e a r t y p i c a l f o r t h i s p h a s e . T h e s e s i t e s h a v e p r o v e n t o b e e x t r e m e l y p r o d u c t i v e . U n m a n a g e d m a t u r e 7 0 - y e a r - o l d s t a n d s h a v e e s t i m a t e d y i e l d s o f 1 2 t o 1 5 c u m / h a / y r ( C S C W o r k s h o p , 1 9 8 3 ) . H o w e v e r , c o m p a r i s o n o f h e i g h t g r o w t h i n y o u n g 1 0 t o 1 5 y e a r o l d p l a n t a t i o n s w i t h t h o s e o f B r i t i s h y i e l d c u r v e s ' C o a s t a l S i l v i c u l t u r a l C o m m i t t e e . 1 9 8 3 . U n p u b l i s h e d p r o c e e d i n g s o f t h e n o r t h e r n V a n c o u v e r I s l a n d 1 9 8 3 C S C W o r k s h o p o n t h e C o a s t a l W e s t e r n H e m l o c k Z o n e . - 3 3 -( s e e B r a d l y , 1 9 7 1 ) s u g g e s t t h a t p o t e n t i a l y i e l d s o f n e w l y e s t a b l i s h e d p l a n t a t i o n s c o u l d b e s i g n i f i c a n t l y i n c r e a s e d i f i n t e n s i v e m a n a g e m e n t , p a r t i c u l a r l y i n t h e f o r m o f s t o c k i n g c o n t r o l , w e r e p r a c t i s e d . T r a d i t i o n a l m a n a g e m e n t o f b o t h p h a s e s h a s c o n s i s t e d m a i n l y o f c l e a r c u t t i n g a n d t h e n b r o a d c a s t b u r n i n g f o l l o w e d b y p l a n t i n g , p r i m a r i l y w i t h S i t k a s p r u c e . I t h a s r e c e n t l y b e c o m e e v i d e n t h o w e v e r , t h a t t h e r e i s a s u b s t a n t i a l d i f f e r e n c e i n t h e p e r f o r m a n c e a n d p r o d u c t i v i t y o f t h e p l a n t a t i o n s b e t w e e n t h e t w o p h a s e s . P l a n t a t i o n s e s t a b l i s h e d o n t h e C H - p h a s e , w h i l e i n i t i a l l y p e r f o r m i n g w e l l i n b o t h s u r v i v a l a n d h e i g h t g r o w t h f o r a p e r i o d o f 3 t o 5 y e a r s a f t e r p l a n t i n g , a r e n o w e x p e r i e n c i n g a s e v e r e d e c l i n e i n g r o w t h ( F i g u r e s 5 t o 7 ) . T h e m e a n a n n u a l h e i g h t g r o w t h i n 1 9 8 2 a n d 1 9 8 3 f o r t h e f i v e p l a n t a t i o n s i n t h i s s t u d y w a s o n l y 1 0 . 5 a n d 9 . 6 c m , r e s p e c t i v e l y . T h e d e c l i n e t h e s e p l a n t a t i o n s a r e e x p e r i e n c i n g b e c o m e s e v e n m o r e d r a m a t i c w h e n c o m p a r e d t o t h e e x c e l l e n t p e r f o r m a n c e o f t h e r e g e n e r a t i o n o n t h e H A - p h a s e a n d t h e f a c t t h a t t h e s e t w o p h a s e s o f t e n o c c u r a d j a c e n t t o e a c h o t h e r ( F i g u r e 5 ) . U n l i k e t h e p l a n t a t i o n s e s t a b l i s h e d o n t h e C H - p h a s e , t h e p l a n t a t i o n s e s t a b l i s h e d o n t h e H A - p h a s e h a v e c o n t i n u e d t o p e r f o r m w e l l ( F i g u r e s 5 t o 7 ) . A s m e n t i o n e d e a r l i e r , e x t r e m e l y d e n s e a n d v i g o r o u s n a t u r a l h e m l o c k a n d a m a b i l i s r e g e n e r a t i o n t y p i c a l l y d e v e l o p o n t h e s e s i t e s a f t e r l o g g i n g . H e m l o c k g r o w t h i n t h e s e s t a n d s w a s e q u i v a l e n t o r b e t t e r t o t h a t o f s p r u c e . F o r e x a m p l e , t h e 1 9 8 2 a n d 1 9 8 3 m e a n a n n u a l h e i g h t i n c r e m e n t f o r 1 0 c o - d o m i n a n t s p r u c e a n d h e m l o c k - 3 4 -F I G U R E 5 . D e v e l o p m e n t o f p l a n t a t i o n s o n t h e H A - a n d C H - p h a s e s a f t e r l o g g i n g . R i c k F o u r n i e r i s s e e n h e r e s t a n d i n g i n t w o p l a n t a t i o n s w h i c h w e r e b o t h e s t a b l i s h e d i n 1 9 7 3 . T h e s e p h o t o s w e r e t a k e n a p p r o x i m a t e l y 4 0 m a p a r t . ) H A - p h a s e , -35-FIGURE 6. I l l u s t r a t i o n s o f g r o w t h p a t t e r n s f o r S i t k a s p r u c e g r o w i n g on t h e C H - p h a s e s . Note t h e n a t u r a l l y o c c u r r i n g c e d a r i n c e n t e r o f p h o t o a ) , c u r r e n t h e i g h t g r o w t h i s a b o u t 25 cm compared t o 8 cm f o r t h e s p r u c e . -36-J 1 I ! ! I I I I rjr- 2~ 5 g g tO 1 2 1 4 16 YEARS FROM PLANTING FIGURE 7. Mean c u m u l a t i v e h e i g h t g r o w t h o f S i t k a s p r u c e on t h e CH- and H A - p h a s e s . Means a r e b a s e d on 14 and 10 s a m p l e t r e e s f o r t h e CH- and H A - p h a s e s , r e s p e c t i v e l y . - 3 7 -s e l e c t e d f r o m a 1 6 - y e a r - o l d p l a n t a t i o n was 6 3 . 2 and 7 2 . 2 cm f o r s p r u c e and 5 6 . 9 and 8 7 . 3 cm f o r h e m l o c k , r e s p e c t i v e l y . S i m i l a r h e m l o c k i n g r e s s d o e s n o t o c c u r t o t h e same e x t e n t on t h e C H - p h a s e and e s t i m a t e s o f d e n s i t i e s u s u a l l y a v e r a g e l e s s t h a n 400 s t e m s / h a . W h i l e t h e h e i g h t g r o w t h o f t h e s e h e m l o c k a p p e a r s t o be b e t t e r t h a n t h a t o f t h e s p r u c e ( 1 6 . 9 and 1 7 . 1 cm i n 1982 and 1983 r e s p e c t i v e l y ) i t i s s t i l l p o o r and w e l l b e l o w t h a t o f t h e H A - p h a s e . C o n s i d e r a b l y more c e d a r i n g r e s s o c c u r s i n t h i s p h a s e t h a n i n t h e H A - p h a s e , and w h i l e no g r o w t h e s t i m a t e s h a v e been o b t a i n e d f o r t h i s s p e c i e s , i t i s t h e p r e f e r r e d s p e c i e s f o r t h e s i t e and i s c a p a b l e o f p r o d u c i n g a c c e p t a b l e g r o w t h ( D u m o n t , p e r s o n a l c o m m u n i c a t i o n ) . L e w i s ( 1 9 8 2 ) h y p o t h e s i z e d t h a t t h e m a i n r e a s o n u n d e r l y i n g t h e d i f f e r e n c e s i n p r o d u c t i v i t y b e t w e e n t h e two p h a s e s was r e l a t e d t o t h e d i f f e r e n c e s i n s t a n d d e v e l o p m e n t and i t s e f f e c t on n u t r i e n t t u r n o v e r . He s u g g e s t s t h a t t h e p e r i o d i c w i n d t h r o w d i s t u r b a n c e s o f t h e H A - p h a s e h a s had a " c u l t i v a t i n g e f f e c t " on t h e s o i l s , c r e a t i n g a much more f a v o u r a b l e p h y s i c a l and c h e m i c a l e n v i r o n m e n t f o r r o o t d e v e l o p m e n t and t r e e g r o w t h . D e s c r i p t i o n s o f a t y p i c a l s o i l p r o f i l e f o r b o t h p h a s e s a r e g i v e n i n T a b l e s 3 t o 5 and F i g u r e 8 . A l t h o u g h t h e s o i l s i n b o t h p h a s e s c a n be p r e d o m i n a n t l y c l a s s i f i e d a s a D u r i c F e r r o - H u m i c P o d z o l ( C a n . D e p t . A g r . , 1 9 7 8 ) , t h e i r p h y s i c a l p r o p e r t i e s a r e q u i t e d i s s i m i l a r . The H A - p h a s e i s c h a r a c t e r i z e d by h a v i n g deep (1+ m ) , w e l l d r a i n e d s o i l s o f l o o s e c o n s i s t e n c y . O r g a n i c a c c u m u l a t i o n s t e n d t o be l e s s i n t h i s p h a s e , a l t h o u g h i t - 3 8 -F I G U R E 8 . T y p i c a l s o i l p r o f i l e s of the HA- and CH-phases. P r o f i l e s shown were dug on the same day and occupy the same r e l a t i v e t o p o g r a p h i c l o c a t i o n . a ) H A - p h a s e — n o t e t h e l a c k o f v e g e t a t i o n on t h e f o r e s t f l o o r . A l s o n o t e t h e l a c k o f water a c c u m u l a t i o n d e s p i t e t h e f a c t t h a t t h e p i t i s 1+ m deep. to C H - p h a s e - - n o t e t h e d e n s e s a l a l g r o w t h i n t h i s p h a s e . W a t e r a c c u m u l a t i o n b e g a n a t a d e p t h o f 6 0 cm f r o m t h e t o p o f t h e f o r e s t f l o o r . - 3 9 -TABLE 3. S o i l p r o f i l e d e s c r i p t i o n of the CH-phase . HORIZON DEPTH DESCRIPTION (cm) LF 27 - 26 M i x t u r e of c o n i f e r o u s and s a l a l l i t t e r and mosses; loose c o n s i s t e n c y ; no r o o t s ; abrupt wavy boundary t o , H 2 6 - 0 Reddish b lack (5R 2.5/1 m), dark r e d d i s h brown (5YR 3/2 d ) ; mass ive ; abundant r o o t s a l l s i z e s ; abrupt wavy boundary t o , Ae 0 - 4 Grey (5YR 6/1 m) to brown (7.5YR 4/2 m); medium subangular b l o c k y , f r i a b l e ; few f i n e and medium r o o t s ; c l e a r , broken boundary t o , Bhf 4 - 1 9 Red (2YR 4/6 m), dark brown to brown (7.5YR 4/4 to -5 /4 d ) ; sandy loam; weak medium subangular b l o c k y ; f i r m when m o i s t ; n o n - s t i c k y and s l i g h t l y p l a s t i c , wet; p l e n t i f u l f i n e r o o t s , few medium and coarse r o o t s ; abrupt wavy boundary t o , Bf 19 - 34 Y e l l o w i s h red (5YR 5/6 m), y e l l o w i s h brown (10YR 5/8 d ) ; sandy loam; medium subangular b l o c k y ; f i r m when moi s t ; non-s t i c k y and n o n - p l a s t i c , wet; few f i n e r o o t s ; abrupt wavy boundary t o , B fg j 34 - 48 Y e l l o w i s h brown (10YR 5/8 m), y e l l o w i s h brown (10YR 5/8 d ) ; g r a v e l l y sandy loam; weak, medium and coarse subangular b l o c k y , extremely f i r m when m o i s t , non-s t i c k y and n o n - p l a s t i c ; no r o o t s ; common f a i n t m o t t l e s , seepage water p r e s e n t ; abrupt wavy boundary t o , BCc 48+ S t r o n g l y cemented to i n d u r a t e d g r a v e l l y sandy loam. - R O -T A B L E 4 . S o i l p r o f i l e d e s c r i p t i o n o f t h e H A - p h a s e . H O R I Z O N D E P T H D E S C R I P T I O N ( c m ) L F 1 5 - 12 V a r i e g a t e d m i x t u r e o f c o n i f e r o u s l i t t e r a n d m o s s e s ; l o o s e c o n s i s t e n c y ; n o t r o o t s a b r u p t w a v y b o u n d a r y t o , H 1 2 - 0 B l a c k ( 2 . 5 Y R 2 . 5 / 0 m ) , d a r k r e d d i s h b r o w n ( 5 Y R 3 / 2 d ) ; h i g h l y d e c o m p o s e d o r g a n i c m a t t e r ; g r a n u l a r , s l i g h t l y g r e a s y i n l o w e r h o r i z o n ; a b u n d a n t r o o t s o f a l l s i z e s ; a b r u p t , w a v y b o u n d a r y t o , A e 0 - 3 G r e y ( 5 Y R 6 / 1 m) t o b r o w n ( 7 . 5 Y R 4 / 2 m ) ; m e d i u m s u b a n g u l a r b l o c k y ; f r i a b l e ; f e w f i n e r o o t s ; c l e a r , b r o k e n b o u n d a r y t o , B h f u 3 - 1 8 R e d d i s h b r o w n ( 2 . 5 Y R 4 / 4 m ) , s t r o n g b r o w n ( 7 . 5 Y R 5 / 8 d ) ; s a n d y l o a m ; w e a k m e d i u m s u b a n g u l a r b l o c k y ; f r i a b l e w h e n m o i s t ; n o n -s t i c k y a n d s l i g h t l y p l a s t i c , w e t ; a b u n d a n t f i n e a n d f e w m e d i u m r o o t s ; a b r u p t w a v y b o u n d a r y t o , S t r o n g b r o w n ( 7 . 5 Y R 5 / 6 m ) , y e l l o w i s h b r o w n ( 1 0 Y R 5 / 8 - 5 / 6 d ) ; g r a v e l l y s a n d y l o a m ; w e a k m e d i u m s u b a n g u l a r b l o c k y ; f r i a b l e w h e n m o i s t ; n o n - s t i c k y a n d n o n - p l a s t i c , w e t ; f e w f i n e r o o t s ; c l e a r w a v y b o u n d a r y t o , Y e l l o w i s h b r o w n ( 1 0 Y R 5 / 8 m ) , b r o w n i s h y e l l o w ( 1 0 Y R 6 / 8 d ) ; g r a v e l l y s a n d y l o a m , w e a k , m e d i u m a n d c o a r s e s u b a n g u l a r b l o c k y , f i r m w h e n m o i s t ; n o n - s t i c k y a n d n o n - p l a s t i c , w e t ; v e r y f e w r o o t s ; f e w f a i n t m o t t l e s ; a b r u p t w a v y b o u n d a r y t o , B f 1 1 8 - 3 3 B f 2 3 3 - 4 8 B f 3 4 8 - 6 3 B f g j l 6 3 - 7 8 B f g j 2 7 8 - 8 8 BC 8 8 + O l i v e g r e y ( 5 Y 5 / 2 d ) , e x t r e m e l y f i r m w h e n m o i s t ; n o r o o t s . -41-i TABLE 5. Physical and chemical description of s o i l profiles from the CH- and HA- phases. PHASE HORIZON DEPTH (cm) PH H20 CaC12 N .1. C/N AVAILABLE MINERALIZABLE P N ppm EXCHANGEABLE BASES C.E.C. Ca K Mg meq/100 g BASE Na SATURATION Sand S i l t Clai % % : CH HA L 27-26 4.0 3.5 39.8 0. 92 0.11 A3 18 .6 FH 26-0 3.4 3.0 52.7 0. 89 0.07 59 10 .1 Ae 0-4 - - _ _ — Bhf 4-19 4.4 3.8 10.6 0. 28 0.05 38 1 .0 Bf 19-34 5.0 4.6 A.5 0. 17 0.05 27 1 .0 Bfgj 34-48 5.0 4.6 2.9 0. 10 0.05 29 1 .2 BCc 48+ - _ _ L FH Ae Bhf u Bf 1 Bf 2 Bf 3 Bfgjl Bfgj2 BC 15-12 12-0 0-3 3-18 18-33 33-48 48-63 63-78 78-88 88+ 3.5 3.5 3.1 3.0 51.5 52.6 9.3 2.2 1.3 0.8 1.2 1.7 0.97 1.38 0.28 0.09 0.06 0.03 0.03 0.02 0.09 0.08 0.04 0.03 0.03 0.02 0.03 0.02 57 38 33 25 21 27 41 86 18.8 15.3 2.0 1.8 1.8 1.7 135 119 18 10 2 209 161 31 18 5 2 111.2 9. 93 1.59 5.80 0.22 15.8 -151.3 13. 97 1.62 6.38 0.46 14.8 - - -51.4 0. 21 0.07 0.A1 0.10 1.5 57 36 7 30.4 0. 21 0.03 0.04 0.04 3.7 49 41 10 27.4 0. 05 0.01 0.02 0.01 0.3 70 27 3 120.5 10. 65 1.10 4.AO 0.39 13.7 170.0 22. 55 1.68 5.55 0.21 17.6 - - • -47.2 0. 51 0.09 0.56 0.09 2.6 49 41 10 28.7 0. AO 0.0A 0.50 0.08 3.7 62 29 9 19.7 0. 31 0.03 0.40 0.08 4.1 57 38 5 18.A 0. 27 0.02 0.15 0.06 2.7 66 30 4 19.8 0. 24 0.03 0.12 0.06 2.3 61 35 4 21.6 0. 21 0.02 0.08 0.04 1.6 69 29 2 - 4 2 -a p p e a r s t o v a r y w i t h l o g g i n g . L e w i s ( 1 9 8 2 ) f o u n d t h a t o r g a n i c a c c u m u l a t i o n s i n t h e H A - p h a s e a v e r a g e d b e t w e e n 5 t o 1 0 c m . S i m i l a r a c c u m u l a t i o n s w e r e f o u n d i n t h i s s t u d y i n t h e m a t u r e u n l o g g e d s t a n d s . A r e a s w h i c h h a d b e e n d i s t u r b e d b y l o g g i n g h o w e v e r , h a d m u c h m o r e v a r i a b l e d e p t h s w i t h a c c u m u l a t i o n s o f t e n e x c e e d i n g 2 0 c m . T h e C H - p h a s e i s c h a r a c t e r i z e d b y h a v i n g a t h i c k e r ( 1 5 t o 3 0 c m ) , s o m e w h a t c o m p a c t e d o r g a n i c l a y e r . T h e B f h o r i z o n i s o f f i r m c o n s i s t e n c y a n d o n l y m o d e r a t e l y d e e p d u e t o a h i g h l y c e m e n t e d t i l l l a y e r w h i c h o c c u r s a t a d e p t h o f 4 0 t o 5 0 c m . T h e c o m p a c t e d n a t u r e o f t h i s s o i l s t r o n g l y i n f l u e n c e s w a t e r m o v e m e n t a n d t h u s t h e y t e n d t o b e o n l y i m p e r f e c t l y t o m o d e r a t e l y w e l l d r a i n e d ( F i g u r e 8 ) . A d i s t i n g u i s h i n g f e a t u r e o f t h e C H - a n d H A - p h a s e , a s i d e f r o m t h e d i f f e r e n c e i n p r o d u c t i v i t y , i s t h e p r e s e n c e o r a b s e n c e o f s a l a l . T h e C H - p h a s e i s c h a r a c t e r i z e d b y h a v i n g a n e x t r e m e l y d e n s e s a l a l c o v e r , w h e r e a s i n t h e H A - p h a s e i t i s v i r t u a l l y a b s e n t . T h e r e h a s b e e n s o m e s u g g e s t i o n t h a t s a l a l may i n p a r t c o n t r i b u t e t o t h e l o w p r o d u c t i v i t y o f t h e C H - p h a s e . S t r o n g s i m i l a r i t i e s h a v e b e e n n o t e d b e t w e e n t h e p e r f o r m a n c e o f t h e s e p l a n t a t i o n s a n d o f t h e S i t k a s p r u c e p l a n t a t i o n s i n B r i t a i n s u f f e r i n g f r o m " h e a t h e r " ( C a l l u n a v u l g a r i s ) ( L . ) H u l l , c h e c k ( W e e t m a n , p e r s o n a l c o m m u n i c a t i o n ) . S o m e p o s s i b l e r e a s o n s f o r a " s a l a l " e f f e c t m i g h t b e a t t r i b u t e d t o : ( 1 ) E x c e s s i v e c o m p e t i t i o n f o r a l i m i t e d s u p p l y o f a v a i l a b l e n u t r i e n t s . On t h e s e s i t e s s a l a l f o r m s a v e r y d e n s e r o o t m a t w h i c h e x p l o i t s t h e e n t i r e o r g a n i c l a y e r a n d t h e u p p e r p o r t i o n s o f t h e m i n e r a l s o i l a n d i s t h u s i n d i r e c t c o m p e t i t i o n w i t h t h e s p r u c e . - 4 3 -( 2 ) P r e s e n c e o f h i g h c o n c e n t r a t i o n s o f o r g a n i c c o m p o u n d s s u c h a s p o l y p h e n o l s a n d s i m p l e f a t t y a c i d s i n t h e s a l a l l i t t e r . T h e s e s u b s t a n c e s a r e r e s i s t a n t t o m i c r o b i a l a t t a c k ( M i n d e r m a n , 1 9 6 6 ) a n d p o s s e s s f u n g a l - a n d p h y t o t o x i c p r o p e r t i e s c a p a b l e o f s u p p r e s s i n g t h e d e c o m p o s i n g m i c r o - o r g a n i s m s ( B e r g e t a l . , 1 9 8 0 ) a n d i n h i b i t i n g r o o t g r o w t h ( J a l a l a n d R e a d , 1 9 8 3 a , b ) . W h i l e i t i s n o t k n o w n i f s a l a l h a s h i g h c o n c e n t r a t i o n s o f t h e s e c o m p o u n d s , t h e y a r e a p p a r e n t l y r e a d i l y p r o d u c e d i n m a n y e v e r g r e e n s c l e r o p h y l l o u s h e a t h - f o r m i n g s p e c i e s o f t h e E r i c a c e a e f a m i l y ( S p e c h t , 1 9 7 9 ) . M o r e o v e r , l e a f p o l y p h e n o l p r o d u c t i o n t e n d s t o i n c r e a s e i n p l a n t s e x p o s e d t o n u t r i e n t s t r e s s ( D a v i e s e t a l . , 1 9 6 4 ; G o s z , 1 9 8 1 ) . R e c e n t l y , J a l a l a n d R e a d ( 1 9 8 3 a , b ) h a v e e x t r a c t e d a n d i d e n t i f i e d a n u m b e r o f t h e s e c o m p o u n d s f r o m C a l l u n a h e a t h s o i l s i n c o n c e n t r a t i o n s s i g n i f i c a n t l y h i g h e r t h a n l e v e l s w h i c h h a v e b e e n p r e v i o u s l y s h o w n t o t o t a l l y i n h i b i t r o o t g r o w t h i n a g r i c u l t u r a l c r o p s a n d s e v e r e l y i n h i b i t f u n g a l m y c e l i a l g r o w t h i n f o r e s t s o i l s . ( 3 ) A p o s s i b i l i t y o f a n a l l e l o p h a t h i c i n f l u e n c e b e i n g e x e r t e d b y t h e s a l a l . A l l e l o p a t h y i s a c o m m o n l y k n o w n p h e n o m e n o m a m o n g s t m a n y p l a n t s p e c i e s ( f o r e x a m p l e s e e R i c e , 1 9 7 9 ) . I n p a r t i c u l a r h o w e v e r , a l l e l o p a t h i c p r o p e r t i e s h a v e b e e n c o m m o n l y a s s o c i a t e d w i t h E r i c a c e a e s p e c i e s i n d i f f e r e n t p a r t s o f t h e w o r l d ( H a n d l e y , 1 9 6 3 ; P e t e r s o n , 1 9 6 5 ; J a l a l a n d R e a d , 1 9 8 3 a , b ) . I n t h e c a s e o f C a l l u n a h e a t h s , i t h a s b e e n s u g g e s t e d t h a t m e t a b o l i t e s p r o d u c e d b y t h e m y c o r r h i z a l f u n g i o f C a l l u n a r o o t s may b e t o x i c t o t h e m y c o r r h i z a l f u n g i o f t r e e s p e c i e s ( H a n d l e y , 1 9 6 3 ; R o b i n s o n , 1 9 7 2 ) . J a l a l a n d R e a d ( 1 9 8 3 a , b ) s u g g e s t e d t h a t t h e m y c o r r h i z a e o f C a l l u n a may b e b e t t e r a b l e t o u t i l i z e l i p i d s a s a c a r b o n s o u r c e a n d w o u l d t h u s b e a b l e t o t o l e r a t e t h e h i g h c o n c e n t r a t i o n s o f f a t t y a c i d r e s i d u e s p r o d u c e d . A s m e n t i o n e d a b o v e , t h e s e r e s i d u e s a r e h i g h l y t o x i c t o m a n y o t h e r f u n g a l s p e c i e s . M o s t E r i c a c e o u s s p e c i e s h a v e b e e n s h o w n t o f o r m a d i s t i n c t m y c o r r h i z a l a s s o c i a t i o n k n o w n a s " e r i c o i d " m y c o r r h i z a e r a t h e r t h a n t h e e c t o - o r v e s i c u l a r - a r b u s c u l a r ( V A - ) m y c o r r h i z a e t y p i c a l l y f o u n d o n o t h e r v a s c u l a r p l a n t s ( P e a r s o n a n d R e a d , 1 9 7 3 ; L a r g e n t e t a l . , 1 9 7 9 ; M o l i n a a n d T r a p p e , 1 9 8 2 ) . P e a r s o n a n d R e a d ( 1 9 7 3 ) h a v e s h o w n t h a t t h e e n d o p h y t e s w h i c h r e a d i l y f o r m m y c o r r h i z a l a s s o c i a t i o n w i t h C a l l u n a a l s o r e a d i l y i n f e c t o t h e r E r i c a c e a e s p e c i e s . S a l a l h a s a l s o b e e n - 4 4 -s h o w n t o f o r m t h e t y p i c a l " e r i c o i d " t y p e m y c o r r h i z a l a s s o c i a t i o n ( L a r g e n t e t a l . , 1 9 7 9 ) . M c N a b b ( 1 9 6 1 ) n o t e d t h a t t h e e r i c o i d m y c o r r h i z a e o n G a u l t h e r i a s p e c i e s i n New Z e a l a n d w e r e a n a t o m i c a l l y s i m i l a r t o t h a t f o u n d o n C a l l u n a v u l g a r i s i n B r i t a i n . ( 4 ) T h e t y p e , q u a l i t y a n d q u a n t i t y o f l i t t e r i n p u t . I n a d d i t i o n t o t h e p o s s i b l e i n p u t o f t o x i c o r g a n i c c o m p o u n d s , t h e h i g h r o o t i n g d e n s i t i e s o f s a l a l may r e s u l t i n a s u b s t a n t i a l a m o u n t o f w o o d y r o o t l i t t e r l e a d i n g t o t h e d e v e l o p m e n t o f a t h i c k " r o o t " m o r h u m u s w i t h a h i g h C / N r a t i o . R e c e n t l y , Y o u n g b e r g ( 1 9 7 8 ) s h o w e d t h a t n i t r o g e n m o b i l i z a t i o n a n d s u b s e q u e n t u p t a k e b y D o u g l a s - f i r s e e d l i n g s g r o w n i n d i f f e r e n t f o r e s t f l o o r m a t e r i a l s w a s s i g n i f i c a n t l y l e s s w h e n t h e h u m u s m a t e r i a l h a d a s a l a l c o m p o n e n t d e s p i t e a h i g h e r N c o n c e n t r a t i o n . T h e s e f i n d i n g s l e d Y o u n g b e r g t o s u g g e s t t h a t s o m e t h i n g o t h e r t h a n t o t a l N w a s p l a y i n g a n i m p o r t a n t r o l e i n i n f l u e n c i n g g r o w t h a n d N u p t a k e . A l t h o u g h n o t i n v e s t i g a t e d i n t h i s t h e s i s , t h e p o s s i b i l i t y o f s o m e s o r t o f " s a l a l e f f e c t " c a n n o t b e d i s c o u n t e d . T h i s s h o u l d b e k e p t i n m i n d t h r o u g h o u t t h i s t h e s i s . -45-C O M P A R I S O N S OF S O I L N U T R I E N T S T A T U S AND N I T R O G E N M I N E R A L I Z A T I O N P O T E N T I A L OF T H E C H - AND H A - P H A S E S I N T R O D U C T I O N T h e g e n e r a l a p p e a r a n c e o f t h e p l a n t a t i o n s i n t h e C H - p h a s e , i . e . , s e v e r e c h l o r o s i s a n d g r o w t h c h e c k , s t r o n g l y s u g g e s t s t h e p o s s i b i l i t y o f a n u t r i e n t d i s o r d e r , a n d i n p a r t i c u l a r , a n i t r o g e n d e f i c i e n c y . P r e l i m i n a r y f o l i a r a n d s o i l a n a l y s i s ( L e w i s , 1 9 8 2 ) s u p p o r t s t h i s s u g g e s t i o n . A s m e n t i o n e d e a r l i e r , L e w i s h y p o t h e s i z e d t h a t o r g a n i c d e c o m p o s i t i o n a n d n u t r i e n t t u r n o v e r w e r e m u c h s l o w e r i n t h e C H - p h a s e a s c o m p a r e d t o t h e H A - p h a s e . I f s u c h i s t h e c a s e , d i f f e r e n c e s i n t h e s o i l n u t r i e n t s t a t u s , a n d i n p a r t i c u l a r , N m i n e r a l i z a t i o n r a t e s , s h o u l d b e e x p e c t e d b e t w e e n t h e t w o p h a s e s . T h e r e f o r e , s o i l s a m p l e s w e r e c o l l e c t e d f r o m b o t h p h a s e s a n d a n a l y z e d i n o r d e r t o i d e n t i f y p o s s i b l e d i f f e r e n c e s . I t i s n o t t h e i n t e n t o f t h i s s t u d y t o q u a n t i f y t h e a b s o l u t e a m o u n t s o f n u t r i e n t s o n t h e s e s i t e s , b u t r a t h e r , t o o b t a i n a n i n d i c a t i o n o f r e l a t i v e d i f f e r e n c e s b e t w e e n t h e t w o p h a s e s . T h u s , a l t h o u g h t h e s a m p l e s i z e p e r c u t o v e r i s s m a l l ( s e e M e t h o d s ) , i t s h o u l d b e l a r g e e n o u g h t o a d e q u a t e l y d i s t i n g u i s h d i f f e r e n c e s b e t w e e n t h e t w o p h a s e s . - 4 6 -M A T E R I A L S AND M E T H O D S F i e l d P r o c e d u r e M a n y o f t h e S i t k a s p r u c e p l a n t a t i o n s e s t a b l i s h e d o n t h e C H - p h a s e e x p e r i e n c e d a n i n i t i a l p e r i o d o f g o o d g r o w t h b e f o r e t h e o n s e t o f t h e d e c l i n e . T h e A s s a r t e f f e c t h a s b e e n s u g g e s t e d a s a p o s s i b l e e x p l a n a t i o n f o r t h i s i n i t i a l g r o w t h ( W e e t m a n , p e r s o n a l c o m m u n i c a t i o n s ) . T h e r e f o r e , i n o r d e r t o i n v e s t i g a t e t h i s p o s s i b i l i t y , a n a g e s e q u e n c e o f c u t o v e r s w e r e s e l e c t e d f o r s a m p l i n g . F i v e p l a n t a t i o n s , w h i c h w e r e i n i t i a l l y l o g g e d a n d t h e n b u r n e d 3 , 5 , 9 , 1 4 a n d 2 4 y e a r s a g o , p l u s a m a t u r e u n l o g g e d s t a n d , w e r e s e l e c t e d f r o m e a c h p h a s e . T h e 9 a n d 1 4 y e a r o l d c u t o v e r s w e r e s u b s e q u e n t l y u s e d f o r t h e f e t i l i z e r t r i a l s . I n e a c h o f t h e u n f e r t i l i z e d p l a n t a t i o n s , s a m p l e s w e r e t a k e n a l o n g f i v e , 1 0 0 m t r a n s e c t s u s i n g a s o i l c o r e s a m p l e r . A l o n g e a c h t r a n s e c t , f i v e s a m p l e s o f t h e t o p 1 5 cm o f t h e F H l a y e r a n d t h r e e s a m p l e s o f t h e t o p 1 5 cm o f m i n e r a l s o i l w e r e c o l l e c t e d a t 2 0 m i n t e r v a l s a n d p l a c e d i n i n d i v i d u a l p l a s t i c b a g s . I n t h e f e r t i l i z e d p l a n t a t i o n s , s a m p l i n g w a s r e s t r i c t e d t o t h e p e r i m e t e r o f f i v e o f t h e c o n t r o l p l o t s . L a r g e r o o t s a n d p o o r l y d e c o m p o s e d w o o d y m a t e r i a l w e r e a v o i d e d i n a l l p h a s e s o f s a m p l i n g . T h e c o r e s w e r e l a t e r b u l k e d b y t r a n s e c t o r p l o t t o g i v e a t o t a l o f t e n ( f i v e F H a n d f i v e m i n e r a l s o i l ) s a m p l e s p e r p l a n t a t i o n . A t - 4 7 -t h e t i m e o f s a m p l i n g , t o t a l d e p t h o f o r g a n i c a c c u m u l a t i o n t o m i n e r a l s o i l was m e a s u r e d a t e a c h s a m p l i n g s p o t . L a b o r a t o r y A n a l y s i s A l l s a m p l e s , o r g a n i c and m i n e r a l , were i n i t i a l l y a i r d r i e d f o r one week, and t h e n s i f t t h r o u g h a 2-mm s i e v e . A s u b s a m p l e o f 50 g f r o m e a c h s a m p l e was t h e n t a k e n and c o m p o s i t e d by t r a n s e c t o r p l o t and s o i l f r a c t i o n . A f u r t h e r s u b s a m p l e was t a k e n and f i n e l y g r o u n d f o r t h e d e t e r m i n a t i o n o f t o t a l N, P and C. M i n e r a l i z a b l e - N was d e t e r m i n e d on d u p l i c a t e s a m p l e s u s i n g t h e a n a e r o b i c i n c u b a t i o n method o f W a r i n g and B r e n n e r ( 1 9 6 4 ) . Two grams o f f o r e s t f l o o r and f i v e grams o f m i n e r a l s o i l were i n c u b a t e d i n 23 ml o f w a t e r f o r two weeks a t 30°C. M i n e r a l i z a b l e - N was t h e n e x t r a c t e d by s h a k i n g t h e s o l u t i o n f o r one h o u r i n 1 N KC1. The e x t r a c t was a n a l y z e d c o l o r i m e t r i c a l l y w i t h a T e c h n i c o n a u t o a n a l y z e r f o r ammonium. N i t r a t e c o n c e n t r a t i o n s were n o t d e t e r m i n e d . Due t o t h e l o g i s t i c s o f s a m p l e s t o r a g e and t r a n s p o r t a t i o n i n t h e f i e l d , s a m p l e s were e x p o s e d t o room t e m p e r a t u r e c o n d i t i o n s f o r a p e r i o d o f one t o two weeks p r i o r t o t h e commencement o f a i r d r y i n g . T h u s , t h e d a t a i n t h i s s t u d y w i l l m a i n l y be e x p r e s s e d a s g r o s s N m i n e r a l i z a t i o n ( J o n e s and P a r s o n s , 1970; P o w e r s , 1980) r a t h e r t h a n n e t m i n e r a l i z a t i o n . However, f o r p u r p o s e s o f c o m p a r i s o n w i t h o t h e r s t u d i e s , n e t m i n e r a l i z a t i o n was a l s o d e t e r m i n e d . T h u s , p r i o r t o i n c u b a t i o n , a v a i l a b l e N was e x t r a c t e d f r o m d u p l i c a t e s a m p l e s u s i n g t h e same methods as a b o v e . Net m i n e r a l i z a b l e - N was t h e n d e t e r m i n e d by - 4 8 -s u b t r a c t i n g t h e a m o u n t r e l e a s e d d u r i n g t h e i n c u b a t i o n f r o m t h e a m o u n t o f a v a i l a b l e N i n i t i a l l y p r e s e n t i n t h e s o i l . T o t a l N a n d P w e r e d e t e r m i n e d b y a s e m i m i c r o K j e l d a h l d i g e s t i o n , t h e n a n a l y z e d c o l o r i m e t r i c a l l y w i t h a T e c h n i c o n a u t o a n a l y z e r . T o t a l C w a s a n a l y z e d u s i n g a L e c o I n d u c t i o n F u r n a c e . A v a i l a b l e P w a s d e t e r m i n e d u s i n g t h e B r a y P e x t r a c t i o n p r o c e d u r e ( d i l u t e a c i d - f l u o r i d e e x t r a c t i o n ) ( O l s e n a n d S o m m e r s , 1 9 8 2 ) . E x c h a n g e a b l e c a t i o n s ( K , C a , Mg a n d N a ) w e r e d e t e r m i n e d by d i s p l a c e m e n t o f c a t i o n s b y n e u t r a l n o r m a l NH4OAC ( C h a m p m a n , 1 9 6 5 ) . D i s p l a c e d c a t i o n s w e r e a n a l y z e d b y a t o m i c a b s o r p t i o n . C E C w a s d e t e r m i n e d b y s t e a m d i s t i l l a t i o n o f NH3 ( C h a p m a n , 1 9 6 5 ) . V a l u e s f o r pH w e r e d e t e r m i n e d i n b o t h a 1 : 2 s o i l : 0 . 0 1 M C a C l 2 a n d 1 : 2 s o i l : w a t e r s u s p e n s i o n f o r m i n e r a l s o i l a n d a n 1 : 5 0 . 0 1 M C a C l 2 . a n d 1 : 5 w a t e r s u s p e n s i o n f o r o r g a n i c m a t e r i a l . P a r t i c l e s i z e w a s d e t e r m i n e d b y t h e B o u y o u c o s h y d r o m e t e r m e t h o d ( D a y , 1 9 6 5 ) . S t a t i s t i c a l A n a l y s i s M i n e r a l i z a b l e - N w a s s u b j e c t e d t o a 6 x 2 ( y e a r s s i n c e h a r v e s t x p h a s e ) f a c t o r i a l a n a l y s i s , f o l l o w e d b y a S t u d e n t - N e w m a n K e u l s ' m u l t i p l e r a n g e t e s t . C o m p a r i s o n s o f t h e o t h e r s o i l p a r a m e t e r s w e r e b a s e d o n s i m p l e S t u d e n t - t t e s t s . F o r t h e s e t e s t s , t h e d a t a f r o m a l l c u t o v e r s w e r e c o m b i n e d b y p h a s e . A l l s t a t i s t i c a l a n a l y s e s w e r e p e r f o r m e d w i t h t h e a i d o f U . B . C . ' s c o m p u t e r u s i n g e i t h e r t h e p r o g r a m G E N L I N , f o r t h e f a c t o r i a l a n a l y s i s , o r M I D A S f o r t h e S t u d e n t - t t e s t s . - 4 9 -R E S U L T S AND D I S C U S S I O N T a b l e 6 s u m m a r i z e s t h e e s t i m a t e s o f t h e s o i l n u t r i e n t s i n v e s t i g a t e d . S o i l s i n b o t h p h a s e s a r e a c i d i c . T h e r e w a s n o s i g n i f i c a n c e d i f f e r e n c e i n pH w h e n m e a s u r e d i n a C a C l 2 s o l u t i o n . H o w e v e r , w h e n m e a s u r e d i n a w a t e r s o l u t i o n , t h e pH o f t h e m i n e r a l s o i l i n t h e H A - p h a s e w a s s i g n i f i c a n t l y g r e a t e r ( p = . 0 5 ) ( T a b l e 6 ) . T h e a c t u a l d i f f e r e n c e s h o w e v e r , a r e s l i g h t , a n d w o u l d n o t a c c o u n t f o r d i f f e r e n c e s i n t h e a v a i l a b i l i t y o f n u t r i e n t s b e t w e e n t h e t w o p h a s e s . W i t h t h e e x c e p t i o n o f C a , t h e r e i s r e l a t i v e l y l i t t l e d i f f e r e n c e i n t h e e x c h a n g e a b l e b a s e s b e t w e e n t h e t w o p h a s e s . S i g n i f i c a n t l y g r e a t e r ( p = . 0 1 ) a m o u n t s o f C a f o u n d i n t h e h u m u s o f t h e C H - p h a s e may b e a r e f l e c t i o n o f t h e h i g h e r c e d a r c o n t e n t o f t h i s p h a s e . H o w e v e r , o t h e r s t u d i e s i n t h i s a r e a h a v e f o u n d c o m p a r a b l e c o n c e n t r a t i o n s i n t h e H A - p h a s e ( T a b l e 7 ) . B o t h K a n d Mg c o n c e n t r a t i o n s w e r e s i g n i f i c a n t l y g r e a t e r ( p = . 0 5 ) i n t h e m i n e r a l s o i l o f t h e H A - p h a s e , a l t h o u g h t h e a c t u a l d i f f e r e n c e s b e t w e e n p h a s e s a r e s l i g h t . W h e n c o m p a r e d w i t h a v a r i e t y o f o t h e r s i t e s t h r o u g h o u t t h e P a c i f i c N o r t h w e s t ( s e e H e i l m a n , 1 9 7 9 ) , t h e v a l u e s f o r C a a n d Mg a p p e a r t o b e n o r m a l , b u t K v a l u e s a p p e a r t o b e w e l l b e l o w t h e a v e r a g e f o r b o t h o r g a n i c a n d m i n e r a l s o i l s . T h e r e a r e i n d i c a t i o n s t h a t t h e l o w K l e v e l s e x p e r i e n c e d i n t h i s s t u d y a r e d e f i c i e n t , p a r t i c u l a r l y i n t h e -50-CH-phase. Mean K c o n c e n t r a t i o n s of the humus are comparable t o , or o n l y s l i g h t l y h i g h e r than c o n c e n t r a t i o n s found i n o l i g o t r o p h i c peats known to be K d e f i c i e n t (Gore and A l l e n , 1956; W i l l i a m s et a l . , 1978). In a d d i t i o n , mean f o l i a r K c o n c e n t r a t i o n of spruce t r e e s from both phases are low and i n the c r i t i c a l range ( T a b l e 1 ) . In f a c t , v i s u a l symptoms c h a r a c t e r i s t i c of K d e f i c i e n c y were observed on the o c c a s i o n a l spruce i n the p l a n t a t i o n s s e l e c t e d f o r f e r t i l i z a t i o n (see F i g u r e 20 and c o r r e s p o n d i n g d i s c u s s i o n s ) . S i m i l a r symptoms were not noted on spruce i n the HA-phase. T h i s may be due to a g r e a t e r p o r t i o n of the r o o t s r e a c h i n g and e x p l o i t i n g the m i n e r a l s o i l i n t h i s phase. Both a v a i l a b l e and t o t a l P were s i g n i f i c a n t l y g r e a t e r (p=.01) i n the o r g a n i c and m i n e r a l s o i l s of the HA-phase as compared to the CH-phase. A b s o l u t e d i f f e r e n c e s between the phases were a g a i n s m a l l , and i n both cases, the s o i l s appear to be e x t r e m e l y P d e f i c i e n t . K l i n k a et a l . , (1979) not e d , however, t h a t c a r e must be e x e r c i s e d when i n t e r p r e t i n g a v a i l a b l e P data s i n c e d i f f e r e n t e x t r a c t i o n methods y i e l d d i f f e r e n t r e s u l t s and the best method f o r c o a s t a l B.C. i s s t i l l unknown. Compared to o t h e r s o i l s t h r oughout the P a c i f i c Northwest (see Heilman, 1979) the e s t i m a t e s o b t a i n e d i n t h i s study are w e l l below average, but agree w i t h e s t i m a t e s from o t h e r s i t e s of western Vancouver I s l a n d ( T a b l e 7 ) . S i m i l a r l y , t o t a l P c o n c e n t r a t i o n s are w i t h i n the ranges found on m e s o t r o p h i c and o l i g o t r o p h i c p e a t s , known to be P d e f i c i e n t (Toleman, 1973). In a d d i t i o n , mean f o l i a r P c o n c e n t r a t i o n s of spruce and hemlock sample T A B L E 6 . C o m p a r i s o n o f n u t r i e n t c o n t e n t s i n t h e C H - and H A - p h a s e s a v e r a g e d o v e r a l l c u t o v e r s . V a l u e s i n p a r e n t h e s i s a r e + S D . CH - P H A S E HUMUS HA-PHASE C H -MINERAL PHASE S O I L HA--PHASE pH H20 CaC12 3 . 4 2 . 8 ( 0 . 1 0 9 ) ( 0 . 1 5 7 ) 3 . 4 ( 0 . 1 1 6 ) 2 . 8 ( 0 . 1 3 4 ) 4 . 2 3 . 9 ( 0 . 2 2 4 ) ( 0 . 2 3 1 ) 4 . 4 4 . 0 ( 0 . 2 1 0 ) ( 0 . 1 9 6 ) * T o t a l N ( X ) f 0 . 9 0 ( 0 . 0 8 5 ) 1 .17 ( 0 . 1 3 6 ) ** 0 . 1 8 ( 0 . 0 4 9 ) 0 . 2 6 ( 0 . 0 8 6 ) ** C / N f 59 ( 5 . 9 4 0 ) * * 45 ( 6 . 9 6 0 ) 45 ( 5 . 4 8 0 ) * * 32 ( 4 . 9 9 0 ) KCL E x t r a c t a b l e N (ppm)* 83 ( 1 8 . 9 8 0 ) 129 ( 2 5 . 9 2 1 ) ** 4 . 8 ( 3 . 2 5 3 ) 8 . 7 ( 5 . 3 1 3 ) ** M i n e r a l i z a b l e - N ( p p t n / 133 ( 2 8 . 8 2 0 ) 191 ( 2 9 . 2 0 5 ) ** 18 ( 4 . 4 7 6 ) 36 ( 1 1 . 8 1 7 ) ** T o t a l P (%/ 0 . 0 6 ( 0 . 0 0 7 ) 0 . 0 8 ( 0 . 0 1 1 ) 0 . 0 3 ( 0 . 0 0 8 ) 0 . 0 4 ( 0 . 0 1 3 ) ** A v a i l a b l e P (ppm) 7 . 9 ( 3 . 9 6 6 ) 1 3 . 8 ( 3 . 9 6 4 ) ** 0 . 8 ( 0 . 5 1 7 ) 2 . 0 ( 1 . 1 2 6 ) ** E x c h a n g a b l e B a s e s Ca ( m e q / l O O g ) K ( m e q / l O O g ) Mg ( m e q / l O O g ) Na ( m e q / l O O g ) 1 4 . 3 0 0 . 8 0 6 . 1 0 0 . 5 0 ( 4 . 6 2 0 ) ( 0 . 1 5 6 ) ( 1 . 1 2 9 ) ( 0 . 0 6 1 ) * * 1 0 . 8 0 ( 3 . 3 5 9 ) 0 . 7 6 ( 0 . 1 8 6 ) 5 . 7 0 ( 1 . 0 2 0 ) 0 . 5 1 ( 0 . 0 7 2 ) 0 . 2 7 0 . 0 6 0 . 2 5 0 . 0 5 ( 0 . 2 9 7 ) ( 0 . 0 2 3 ) ( 0 . 0 9 7 ) ( 0 . 0 1 7 ) 0 . 4 1 0 . 0 8 0 . 3 6 0 . 0 6 ( 0 . 2 5 1 ) ( 0 . 0 2 8 ) ( 0 . 1 6 4 ) ( 0 . 0 2 0 ) * * * D e n o t e s s i g n i f i c a n c e a t p - . 0 5 . * * D e n o t e s s i g n i f i c a n c e a t p - . 0 1 . t B a s e d on 30 c o m p o s i t e d s a m p l e s , a l l r e m a i n i n g a n a l y s i s were b a s e d on 20 c o m p o s i t e d s a m p l e s . T A B L E 7. E s t i m a t e s o f s o i l n u t r i e n t c o n t e n t s f o u n d i n o t h e r s t u d i e s on t h e C H - p h a s e and t h e H A - p h a s e and i n o t h e r s o i l s o f V a n c o u v e r I s l a n d , V a l u e s i n p a r e n t h e s i s a r e r a n g e s . LOCATION NUMBER PHASE OR HORIZON TOTAL A V A I L A B L E EXCHANGEABLE P H OF FOREST TYPE N P C / N P Ca K Mg (H20) SOILS (cm) % (ppm) meq/100 g • J e u n e L a n d i n g ' - HA L - H 1 .16 - 6 6 . 6 * 26 0 . 4 2 . 5 4 . 6 - HA 5-15 0 . 2 9 - 3 . 0 * 2 0 . 1 0 . 6 4 . 2 Woss Camp' _ hemlock L - H 1.21 _ 4 6 . 5 * 18 1.2 4 . 5 5 . 3 - h e m l o c k 5-15 0 . 2 8 - 8 . 1 * 1 0 . 1 0 . 3 4 . 8 T . F . L . S 2 5 2 6 HA H 1 .13 0 . ,10 39 14 0 . 7 4 . 6 _ 0 . 7 4 0 . ,09 59 - ( 8 - 2 1 ) ( 0 . 5 - 1 . 1 ) ( 4 . 9 - 4 . 5 ) _ 4 CH H ( 0 . S 9 - 1 . 6 9 ) ( 0 . 08-- 0 . 1 5 ) ( 4 7 - 7 2 ) - 11 0 . 7 1 5 . 6 _ - ( 5 - 1 4 ) ( 0 . 6 5 - 0 . 7 8 ) ( 3 . 7 - 7 . 8 ) -P o r t H a r d y 2 HA H 1 .30 36 1 0 . 4 _ _ _ 3 . 2 HA 0-15 0 . 1 4 30 1 .6 0 . 0 1 0 . 0 7 0 . 1 6 5 . 4 P o r t Hardy"* hemlock FH 1 .00 0 . 0 6 49 _ 16 1.3 1 2 . 2 3 . 6 ( 0 . 8 0 - 0 . 1 3 ) ( 0 . ,04. - 0 . 0 9 ) ( 3 7 - 6 2 ) - ( 5 - 2 5 ) ( 0 . 8 - 2 . 0 ) ( 8 . 5 - 2 2 . 0 H 3 . 3 - 3 . 8 ) - hemlock 6-11 0 . 3 2 42 - 0 . 2 2 0 . 1 4 0 . 3 7 4 . 1 N . V a n . I s . 4 2 CH LFH 1 .03 0 . 0 6 44 _ 25 1.58 9 . 1 6 3 . 2 2 CH Bf 0 . 1 8 47 0 . 1 0 . 0 1 0 . 1 8 0 . 1 4 4 . 9 T o f i n o 5 2 P l a n t a t i o n L - H 0 . 8 9 _ 38 4 2 . 1 1 3 . 3 1.2 8 . 3 2 P l a n t a t i o n 0-14 0 . 1 4 - 28 1 . 3 0 . 3 7 0 . 3 1 0 . 1 1 -W. V a n . I s . 6 4 - 7 hemlock L - H 1 .09 40 2 . 4 1 5 . 8 0 . 5 5 . 6 _ ( 0 . 8 0 - 1 . 5 7 ) - ( 2 4 - 6 3 ) ( 0 . 7 - 3 . 5 ) ( 4 . 9 - 2 6 . 0 ) ( 0 . 2 - 1 . 2 ) ( 1 . 0 - 1 4 . 1 ) _ 4 - 7 hemlock B h - B h f 0 . 2 6 - 32 1 . 3 2 0 . 1 0 . 5 _ ( 0 . 0 8 - 0 . 7 0 ) — ( 2 6 - 4 1 ) ( 0 . 6 - 2 . 0 ) ( 0 . 2 - 3 . 3 ) - ( 0 . 1 - 1 . 1 ) -Based on a S o d i u m B i c a r b o n a t e e x t r a c t i o n . R e m a i n i n g a r e b a s e d on B r a y ' s D i l u t e a c i d - F l u o r i d e e x t r a c t i o n . S o u r c e s : 1 . B a k e r , 1 9 7 0 . 2 . L e w i s , 1 9 8 2 . 3 . Q u e s n e l , 1 9 8 1 . 4 . M . O . F . , 1 9 8 3 ? 5 . B C F P , 1 9 8 1 . 6 . H e i l m a n , 1 9 7 9 . U n p u b l i s h e d d a t a s u p p l i e d by F r e d N u s z d o r f e r o f t h e t h e B r i t i s h C o l u m b i a M i n i s t r y o f F o r e s t s . - 5 3 -t r e e s t a k e n f r o m b o t h p h a s e s w e r e l o w a n d w e l l b e l o w k n o w n c r i t i c a l v a l u e s ( s e e d i s c u s s i o n o f f o l i a r P ) . T o t a l a n d K C 1 e x t r a c t a b l e N i n b o t h t h e o r g a n i c a n d m i n e r a l s o i l s w e r e a l s o s i g n i f i c a n t l y g r e a t e r ( p = . 0 1 ) i n t h e H A - p h a s e . M e a n K C 1 e x t r a c t a b l e N i n t h e h u m u s o f t h e H A - p h a s e w a s c o n s i d e r a b l y h i g h e r t h a n v a l u e s r e p o r t e d b y V o g t a n d E d m o n d s ( 1 9 8 4 ) f o r h i g h s i t e D o u g l a s - f i r o r b y S i d l e a n d S h a w ( 1 9 8 3 ) f o r a n u m b e r o f s p r u c e - h e m l o c k m i c r o - s i t e s i n A l a s k a . E x t r a c t a b l e N e s t i m a t e s f r o m t h e m i n e r a l s o i l s a n d t h e h u m u s o f t h e C H - p h a s e w e r e c o m p a r a b l e t o t h o s e r e p o r t e d b y t h e a b o v e a u t h o r s . C o m p a r e d t o o t h e r s i t e s t h r o u g h o u t t h e P a c i f i c N o r t h w e s t ( s e e H e i l m a n , 1 9 7 9 ) , t o t a l N i n t h e H A - p h a s e a p p e a r s t o b e a b o v e a v e r a g e , b u t l o w e r t h a n a n u m b e r o f s i t e s k n o w n t o b e h i g h l y p r o d u c t i v e ( s e e K l i n k a e t a l . , 1 9 7 9 ) . T o t a l N i n t h e C H - p h a s e o n t h e o t h e r h a n d i s m u c h l o w e r , b u t s t i l l a p p e a r s t o b e a v e r a g e o r o n l y s l i g h t l y b e l o w a v e r a g e . T o t a l N i n b o t h p h a s e s i s c o n s i d e r a b l y l o w e r t h a n t h e e s t i m a t e s o f t o t a l N i n o l i g o t r o p h i c p e a t s i n B r i t a i n w h e r e N d e f i c i e n c i e s a r e c o m m o n ( T o l e m a n , 1 9 7 3 ; W i l l i a m s e t a l . , 1 9 7 8 ) . T h e h i g h e r t o t a l N o f t h e H A - p h a s e h a s r e s u l t e d i n a s i g n i f i c a n t l y l o w e r C / N r a t i o c o m p a r e d t o t h e C H - p h a s e . T h e s e f a c t o r s h a v e l e d L e w i s ( 1 9 8 2 ) t o s u g g e s t t h a t d e c o m p o s i t i o n a n d n u t r i e n t t u r n o v e r a r e m u c h g r e a t e r i n t h e H A - p h a s e . T o t a l N h o w e v e r , i s n o t n e c e s s a r i l y c o r r e l a t e d w i t h t r e e p r o d u c t i v i t y ( K l i n k a e t a l . , 1 9 7 9 ) . S i m i l a r l y , B e r g a n d E k b o h m ( 1 9 8 3 ) h a v e s h o w n t h a t N r e l e a s e v a r i e s w i t h - 5 4 -s i t e a n d c o n c l u d e d t h a t t h e r e i s n o f i x e d C / N r a t i o w h i c h d i c t a t e s w h e t h e r N i s i m m o b i l i z e d o r r e l e a s e d . I n f a c t , t h e r e i s i n c r e a s i n g e v i d e n c e w h i c h s u g g e s t s t h a t o t h e r f a c t o r s , s u c h a s i n i t i a l l i g n i n c o n t e n t o f l i t t e r , a r e m o r e i m p o r t a n t i n r e g u l a t i n g N r e l e a s e t h a n C / N r a t i o s ( B e r g e t a l . , 1 9 8 2 ) . A t t e m p t s t o i m p r o v e e s t i m a t e s o f N a v a i l a b i l i t y h a s l e d r e s e a r c h e r s t o m o v e f r o m t h e s e s t a t i c m e a s u r e m e n t s t o m o r e d y n a m i c a n d b i o l o g i c a l m e a s u r e s s u c h a s i n c u b a t i o n s t u d i e s ( K e e h e y , 1 9 8 0 ) . S u c h m e t h o d s a r e b e l i e v e d t o p r o v i d e a g o o d r e l a t i v e a s s e s s m e n t o f t h e p o t e n t i a l o f d i f f e r e n t s o i l s t o s u p p l y N ( W i l l i a m s e t a l . , 1 9 7 9 ) . F i g u r e 9 i l l u s t r a t e s t h e p a t t e r n s o f g r o s s N m i n e r a l i z a t i o n f o u n d o v e r a n a g e s e q u e n c e o f c u t o v e r s o n e a c h p h a s e f o r b o t h t h e F H - l a y e r a n d t h e t o p 1 5 cm o f m i n e r a l s o i l . I n g e n e r a l , s i g n i f i c a n t l y m o r e N w a s m i n e r a l i z e d i n t h e h u m u s a n d m i n e r a l s o i l s o f t h e H A - p h a s e a s c o m p a r e d t o t h e C H - p h a s e ( F i g u r e 9 ) . P a t t e r n s o f m i n e r a l i z a t i o n o v e r t i m e i n t h e h u m u s w e r e c o n s i d e r a b l y d i f f e r e n t b e t w e e n t h e t w o p h a s e s . A l t h o u g h t h e f l u c t u a t i o n s b e t w e e n s u c c e s s i v e c u t o v e r s o f t h e H A - p h a s e a r e l a r g e , h a r v e s t i n g a p p e a r s t o h a v e h a d l i t t l e i n f l u e n c e o n N m i n e r a l i z a t i o n . M i n e r a l i z a t i o n o n t h e C H - p h a s e h o w e v e r , a p p e a r s t o f o l l o w a s t e a d y d e c l i n e o v e r t i m e . T h e h i g h m i n e r a l i z a t i o n r a t e i n t h e 3 - y e a r - o l d c u t o v e r o f t h e C H - p h a s e i s u n l i k e l y d u e t o c h a n c e s i n c e t h e s a m p l e s f r o m t h e c o n t r o l w e r e s e l e c t e d f r o m a n u n l o g g e d p o r t i o n o f t h e s a m e s t a n d i m m e d i a t e l y a d j a c e n t t o t h e c u t o v e r . - 5 5 -I t s h o u l d b e r e m e m b e r e d , t h a t i n a d d i t i o n t o l o g g i n g , a l l t h e s e s i t e s w e r e a l s o b u r n t . T h e h i g h e r r a t e s o f m i n e r a l i z a t i o n o n t h e m o r e r e c e n t c l e a r c u t s may t h e r e f o r e b e a r e f l e c t i o n o f a n i n c r e a s e i n n u t r i e n t a v a i l a b i l i t y r e s u l t i n g f r o m t h e b u r n r a t h e r t h a n t h e s o - c a l l e d " A s s a r t e f f e c t " . S i m i l a r p a t t e r n s w e r e n o t e v i d e n t i n t h e m i n e r a l s o i l a n d t h u s h a r v e s t i n g o r b u r n i n g a p p e a r s t o h a v e h a d l i t t l e e f f e c t o n N m i n e r a l i z a t i o n i n t h e s e h o r i z o n s . A n a e r o b i c N - m i n e r a l i z a t i o n i s w e l l c o r r e l a t e d w i t h s i t e i n d e x , t r e e g r o w t h a n d g r o w t h r e s p o n s e s t o N f e r t i l i z a t i o n f o r s o m e s o i l s ( P o w e r s , 1 9 8 0 ) . P o w e r s ( 1 9 8 4 ) s u g g e s t s t h a t i n C a l i f o r n i a o n l y t h o s e s o i l s w i t h l e s s t h a n 5 0 ppm m i n e r a l i z a b l e N s h o u l d b e c o n s i d e r e d f o r f e r t i l i z a t i o n . S i m i l a r l y , S h u m w a y a n d A t k i n s o n ( 1 9 7 8 ) o u t l i n e d g e n e r a l g u i d e l i n e s f o r N f e r t i l i z a t i o n w h e n u s i n g n e t N m i n e r a l i z a t i o n ( s e e M a t e r i a l s a n d M e t h o d s f o r d e f i n i t i o n o f " n e t " ) f o r s o i l s i n t h e P a c i f i c N o r t h w e s t . T h e y s u g g e s t e d t h a t s o i l s w i t h < 2 5 ppm N w o u l d i n d i c a t e a h i g h r e s p o n s e p o t e n t i a l , s o i l s t e s t i n g 2 6 - 5 0 ppm N a m o d e r a t e r e s p o n s e p o t e n t i a l , a n d >51 ppm a l o w r e s p o n s e p o t e n t i a l . I n t h e p r e s e n t s t u d y , g r o s s N m i n e r a l i z a t i o n o f ; t h e m i n e r a l s o i l w a s 3 5 . 7 + 1 1 . 8 1 7 ppm a n d 1 7 . 6 +_ 4 . 4 7 6 ppm f o r t h e H A - p h a s e a n d C H - p h a s e , r e s p e c t i v e l y , a n d n e t m i n e r a l i z a t i o n w a s 2 7 . 1 + 9 . 7 8 0 ppm a n d 1 2 . 8 + 5 . 9 9 1 ppm r e s p e c t i v e l y . T h u s , b a s e d o n t h e a b o v e c r i t e r i a , t h e C H -p h a s e w o u l d b e c o n s i d e r e d t o h a v e a h i g h r e s p o n s e p o t e n t i a l , w h e r e a s , t h e H A - p h a s e w o u l d b e c o n s i d e r e d t o h a v e , a t b e s t , -56-P - O I "5 g g s^—^6 YEARS FROM HARVESTING P-05 P-OI 24 "^EARS FROM HARVESTING F IGURE 9. N m i n e r a l i z a t i o n r a t e s o f t h e m i n e r a l s o i l o f t h e H A - p h a s e (— ( ) . L i n e s c o n n e c t i n g t h e same p o i n t s a r e s i g n i f i c a n t l y d i f f e r e n t . V e r t i c a l b a r s + 1 S D . FH l a y e r and t h e ) and t h e C H - p h a s e n o t -57-T A B L E 8 . E s t i m a t e s o f m i n e r a 1 i z a b 1 e N f o r a v a r i e t y o f s i t e s t h r o u g h o u t t h e P a c i f i c N o r t h w e s t a n d i n B r i t a i n . L O C A T I O N NUMBER F O R E S T HORIZON M I N E R A L I Z A B L E N OF S I T E S T Y P E ( c m ) ( p p m ) O r e g o n , W a s h . ' V a n c o u v e r I s . C o w i c h a n L a k e * ' C o w i c h a n L a k e ' ' C o w i c h a n L a k e 3 C o w i c h a n L a k e T o f i n c - 4 T o f i n o 4 T o f i n o « T o f i n o 4 B r i t a i n 5 B r i t a i n 5 B r i t a i n 5 16 D o u g l a s - f i r 0 - 15 4 6 . 6 10 H i g h s i t e Ah 1 9 . 7 D o u g l a s - f i r 17 H i g h s i t e 0 - 3 0 5 8 . 4 * D o u g l a s - f i r 17 H i g h s i t e 0 - 3 0 4 5 . 4 D o u g l a s - f i r 11 Low s i t e 0 - 3 0 2 4 . 3 * d o u g l a s - f i r 11 Low s i t e 0 - 3 0 1 1 . 9 D o u g l a s - f i r 1 D o u g l a s - f i r L F H 2 0 . 0 p l a n t a t i o n 1 D o u g l a s - f i r 0 - 1 4 3 . 0 p i a n t a t i o n 1 w . h e m l o c k FH 1 3 . 8 p l a n t a t i o n 1 w . h e m l o c k 0 - 1 1 2 . 8 p l a n t a t i o n 3 E u t r o p h i c 0 - 1 5 133 p e a t 2 O l i g o t r o p h i c 0 - 1 5 117 p e a t 1 O l i g o t r o p h i c 0 - 1 5 67 p e a t * V a l u e s r e p r e s e n t g r o s s N m i n e r a l i z a t i o n , a l l o t h e r s a r e n e t m i n e r a l i z a t i o n . S o u r c e s : 1 . Shumway a n d A t k i n s o n , 1 9 7 7 . 2 . K l i n k a e t a l . , 1 9 7 9 . 3 . R o y , 1 9 8 3 . 4 4 . B C F P , 1 9 8 3 . 5 5 . W i l l i a m s e t a l . , 1 9 7 9 . R . R o y . 1 9 8 3 . R e l a t i o n s h i p s b e t w e e n N a v a i l a b i l i t y , s i t e p r o d u c t i v i t y , a n d s e v e r a l i n d i c i e s o f s o i l N s t a t u s . U n p u b . F o r e s t r y 504 T e r m P a p e r . U B C , V a n c o u v e r , B . C . 5 ' B r i t i s h C o l u m b i a F o r e s t P r o d u c t s C o . L t d . 1 9 8 3 . P e r s o n a l c o r r e s p o n d e n c e w i t h D . M c M u l l a n , S i 1 v i c u l t u r a l i s t . - 5 8 -o n l y a m o d e r a t e r e s p o n s e p o t e n t i a l . H o w e v e r , b o t h t h e s e c r i t e r i a a p p l y o n l y t o m i n e r a l s o i l ; i t i s d i f f i c u l t t o s a y i f S h u m w a y a n d A t k i n s o n ' s c r i t e r i o n c o u l d b e a p p l i e d t o t h e s i t e s o f t h i s s t u d y s i n c e t h e r e l a t i v e c o n t r i b u t i o n o f t h e h u m u s l a y e r t o s i t e i n d e x o r t r e e g r o w t h c o m p a r e d t o t h a t o f m i n e r a l s o i l i s n o t k n o w n . G i v e n t h e t h i c k o r g a n i c a c c u m u l a t i o n s f o u n d o n t h e s e s i t e s h o w e v e r ( 1 5 t o 3 0 cm i n t h e C H - p h a s e a n d 5 t o 1 5 cm i n t h e H A - p h a s e ) , t h e h u m u s f r a c t i o n may b e m o r e i m p o r t a n t t h a n t h e m i n e r a l s o i l i n r e g u l a t i n g N a v a i l a b i l i t y . T h i s may b e p a r t i c u l a r l y t r u e f o r t h e C H - p h a s e s i n c e t h e m a j o r i t y o f f e e d i n g r o o t s w o u l d p r o b a b l y b e r e s t r i c t e d t o t h e t h i c k e r o r g a n i c l a y e r . M o r e o v e r , t h i s i s s u p p o r t e d b y t h e p a t t e r n s o f N m i n e r a l i z a t i o n o f t h e h u m u s , w h i c h c l o s e l y f o l l o w t h e g r o w t h p a t t e r n s o f p l a n t a t i o n s e s t a b l i s h e d o n e a c h p h a s e ( F i g u r e s 7 a n d 9 ) . T h e r e a r e v e r y f e w s t u d i e s o n N m i n e r a l i z a t i o n a v a i l a b l e f o r c o m p a r i s o n , b u t s o m e o f t h e e s t i m a t e s o b t a i n e d f o r d i f f e r e n t s i t e s t h r o u g h o u t t h e P a c i f i c N o r t h w e s t a n d B r i t a i n a r e g i v e n i n T a b l e 8 . S i n c e N m i n e r a l i z a t i o n h a s b e e n s h o w n t o v a r y w i t h s i t e i n d e x a s w e l l a s a c t u a l m e t h o d s u s e d ( P o w e r s , 1 9 8 0 ; S h u m w a y a n d A t k i n s o n , 1 9 7 8 ) , d i r e c t c o m p a r i s o n s a r e d i f f i c u l t . I n g e n e r a l h o w e v e r , N m i n e r a l i z a t i o n e s t i m a t e s i n t h e m i n e r a l s o i l f o r t h e H A - p h a s e a r e w i t h i n t h e r a n g e s f o u n d f o r h i g h s i t e D o u g l a s - f i r , w h e r e a s , t h o s e f o r t h e C H - p h a s e a r e m o r e c o m p a r a b l e t o N m i n e r a l i z a t i o n r a t e s o f l o w s i t e D o u g l a s - f i r ( T a b l e 8 ) . -59-SUMMARY AND C O N C L U S I O N S T h e g r e a t e r N m i n e r a l i z a t i o n r a t e s o f t h e H A - p h a s e l e n d s u p p o r t t o L e w i s ' s h y p o t h e s i s t h a t d e c o m p o s i t i o n a n d n u t r i e n t t u r n o v e r a r e m u c h s l o w e r i n t h e C H - p h a s e , a n d t h u s may a c c o u n t f o r s o m e o f t h e d i f f e r e n c e s i n p r o d u c t i v i t y b e t w e e n t h e t w o p h a s e s . H o w e v e r , w h i l e s i g n i f i c a n t d i f f e r e n c e s i n m i n e r a l i z a b l e N , t o t a l N , a n d t o t a l a n d a v a i l a b l e P h a v e b e e n n o t e d b e t w e e n t h e p h a s e s , t h e a c t u a l d i f f e r e n c e s d o n o t a p p e a r t o b e l a r g e e n o u g h t o a c c o u n t f o r s u c h d r a m a t i c d i f f e r e n c e s i n p r o d u c t i v i t i e s . T h i s i s p a r t i c u l a r l y t r u e f o r t o t a l a n d a v a i l a b l e P , a n d n e t N m i n e r a l i z a t i o n o f t h e h u m u s . I n f a c t , c o n s i d e r i n g t h e r e l a t i v e l y h i g h m i n e r a l i z a t i o n r a t e s f o u n d i n t h e h u m u s o f b o t h p h a s e s , t h e r e w o u l d a p p e a r t o b e s u f f i c i e n t q u a n t i t i e s o f a v a i l a b l e N i n e i t h e r t o s u s t a i n g r o w t h . M o r e o v e r , t h i s i s s u p p o r t e d b y t h e r e l a t i v e l y g o o d g r o w t h o f c e d a r i n t h e C H - p h a s e . A l s o , w i t h r e s p e c t t o P , f o l i a g e c o n c e n t r a t i o n s o f v i g o u r o u s h e m l o c k a n d s p r u c e s e l e c t e d f r o m t h e H A - p h a s e a r e L o n l y m a r g i n a l l y g r e a t e r t h a n t h e f o l i a g e c o n c e n t r a t i o n s f o u n d i n t h e C H - p h a s e , a n d o n b o t h s i t e s f o l i a r P c o n c e n t r a t i o n s a r e i n t h e d e f i c i e n c y r a n g e ( s e e d i s c u s s i o n o n f o l i a r P ) . C e d a r o n t h e o t h e r h a n d , h a s c o n s i d e r a b l y h i g h e r f o l i a g e P c o n c e n t r a t i o n s w h i c h a p p e a r t o b e a d e q u a t e . T h e s e f i n d i n g s s u g g e s t t h e p o s s i b i l i t y t h a t s o m e f a c t o r ( s ) , o t h e r t h a n t h e -60-l a c k o f a v a i l a b l e n u t r i e n t s , may b e c o n t r i b u t i n g t o t h e d i f f e r e n c e s i n p r o d u c t i v i t y . W h i l e i t i s b e y o n d t h e s c o p e o f t h i s t h e s i s t o f u l l y e x p l o r e t h e s e f a c t o r s a b r i e f d i s c u s s i o n i s p r o v i d e d . D i f f e r e n c e s i n p r o d u c t i v i t y b e t w e e n t h e p h a s e s may b e r e l a t e d t o a p o s s i b l e s a l a l e f f e c t d i s c u s s e d e a r l i e r a n d / o r d i f f e r e n c e s i n t h e s o i l p h y s i c a l p r o p e r t i e s . L e w i s ( 1 9 8 2 ) a l s o s u g g e s t e d t h a t d i f f e r e n c e s i n t h e s o i l p h y s i c a l p r o p e r t i e s b e t w e e n t h e t w o p h a s e s may p l a y a s i g n i f i c a n t r o l e i n c o n t r i b u t i n g t o t h e h i g h e r p r o d u c t i v i t y o f t h e H A - p h a s e . T h e c u l t i v a t i o n e f f e c t o f t h e p e r i o d i c w i n d t h r o w d i s t u r b a n c e s w o u l d f a v o u r r o o t d e v e l o p m e n t a n d p e n e t r a t i o n i n t o t h e m i n e r a l s o i l o f t h i s p h a s e . I f i n f a c t r o o t d e v e l o p m e n t i s p r e d o m i n a n t l y r e s t r i c t e d t o t h e o r g a n i c l a y e r o f t h e C H - p h a s e , t h e n t h e c o m b i n e d c o n t r i b u t i o n o f n u t r i e n t s i n t h e h u m u s a n d m i n e r a l s o i l f r a c t i o n s o f t h e H A - p h a s e w o u l d p r o v i d e a d i s t i n c t a d v a n t a g e i n t e r m s o f t h i s s i t e ' s p o t e n t i a l c a p a b i l i t y t o s u p p l y n u t r i e n t s . - 6 1 -: E F F E C T S OF F E R T I L I Z A T I O N ON 1 9 8 3 L E A D E R G R O W T H , C U R R E N T Y E A R S N E E D L E W E I G H T , AND N E E D L E N U T R I E N T C O M P O S I T I O N I N T R O D U C T I O N E f f i c i e n t o p e r a t i o n a l f o r e s t f e r t i l i z a t i o n d e p e n d s o n i d e n t i f y i n g t h e n u t r i e n t s t h a t l i m i t g r o w t h a n d t h e p o t e n t i a l r e s p o n s i v e n e s s o f t h e s t a n d s t o b e f e r t i l i z e d . E v i d e n c e p r e s e n t e d t h u s f a r i n t h i s a n d o t h e r s t u d i e s s u g g e s t t h e p o s s i b i l i t y o f m u l t i p l e n u t r i e n t d e f i c i e n c i e s e x i s t i n g i n t h e s p r u c e p l a n t a t i o n s o f t h e C H - p h a s e . M u c h o f t h i s e v i d e n c e h o w e v e r , i s b a s e d o n p r e l i m i n a r y d a t a . T h e r e f o r e , a m u c h m o r e d e t a i l e d f o l i a r a n a l y s i s i s r e q u i r e d i n o r d e r t o a c c u r a t e l y i d e n t i f y d e f i c i e n t n u t r i e n t s , a n d f e r t i l i z e r t r i a l s m u s t b e e s t a b l i s h e d t o d e t e r m i n e p o t e n t i a l r e s p o n s e s . C o n v e n t i o n a l f e r t i l i z e r t r i a l s t y p i c a l l y r e q u i r e 3 t o 5 y e a r s t o o b t a i n r e l i a b l e r e s p o n s e i n f o r m a t i o n . M o r e o v e r , t h e y o f t e n r e q u i r e a l a r g e h o m o g e n e o u s a r e a , w h i c h s e v e r e l y r e s t r i c t s t h e n u m b e r o f p l o t s a n d t r e a t m e n t s ( s e e L i t e r a t u r e R e v i e w ) . W e e t m a n a n d F o u r n i e r ( 1 9 8 3 ) s u g g e s t t h a t ; t h e u s e o f m i n i - p l o t s c o m b i n e d w i t h a g r a p h i c a l a p p r o a c h f o r i n t e r p r e t i n g f o l i a r a n a l y s i s c a n p r o v i d e a r a p i d m e t h o d o f t e s t i n g a l a r g e n u m b e r o f d i f f e r e n t t r e a t m e n t s a n d p r o v i d e a q u a l i t a t i v e e s t i m a t e o f p o t e n t i a l g r o w t h r e s p o n s e s . T h i s method i s d e s c r i b e d i n d e t a i l i n t h e L i t e r a t u r e Review, was a d o p t e d h e r e b e c a u s e i t s a d v a n t a g e s i n m e e t i n g o b j e c t i v e s o f t h i s t h e s i s . - 6 3 -MATERIALS AND METHODS F i e l d P r o c e d u r e s F i v e p l a n t a t i o n s , r a n g i n g i n age f r o m 8 t o 1A y e a r s were s e l e c t e d f o r s t u d y . T a b l e 9 g i v e s t h e s t a n d c h a r a c t e r i s t i c s f o r e a c h p l a n t a t i o n . F o r c o n v e n i e n c e , t h e y a r e r e f e r r e d t o a s s t a n d s 1 t o 5; F i g u r e 3 g i v e s t h e c o r r e s p o n d i n g l o c a t i o n o f e a c h s t a n d . TABLE 9 . S t a n d c h a r a c t e r i s t i c s o f f i v e S i t k a s p r u c e p l a n t a t i o n s s e l e c t e d f o r f e r t i l i z a t i o n . STAND YEAR YEAR MEAN* ANNUAL HEIGHT INCREMENT** NUMBER LOGGED PLANTED HEIGHT 1983 1982 1981 (m) (cm) (cm) (cm) 1 1971 1972 (2 . 2.70 31-3.28) 9.8 (5-16) 12.0 (6-23) 9.7 (5-23) 2 - 1969 (2 . 2.AA 13-2.71) 9.5 (3-18) 7.9 (2-19) 10.2 (A-2A) 3 - 1969 (2 . 2.61 26-2.97) 9.2 (2-12) 10.1 (3-16) 11.7 (A-22) A 1972-1973 1975 (1 . 1.96 76-2.33) 10.9 (5-23) 11.1 (2-28) 15.7 (A-38) 5 1971 1973 ( 1 . 2.17 90-2 .A6) 9.2 (2-20) 10.6 (2-20) 11.9 (3-2A) * I n c l u d e s s a m p l e t r e e s f r o m a l l t r e a t m e n t s — r a n g e o f t r e a t m e n t means i n p a r e n t h e s i s . ** O n l y i n c l u d e s s a m p l e t r e e s f r o m c o n t r o l p l o t s — r a n g e s i n p a r e n t h e s i s . - 6 4 -T h e e x p e r i m e n t a l d e s i g n a n d m e t h o d s u s e d i n t h i s s t u d y a r e b a s e d o n t h e s i n g l e t r e e , m i n i - f e r t i l i z e r p l o t s a f t e r W e e t m a n a n d F o u r n i e r ( 1 9 8 3 ) . A c o m p l e t e l y r a n d o m i z e d . 4 x 2 x 2 f a c t o r i a l d e s i g n ( ( N O , N l , N 2 , N 3 ) x ( P O + K O , P , K , P K ) ) w i t h s e v e n r e p l i c a t i o n s p e r t r e a t m e n t w a s e s t a b l i s h e d i n e a c h o f t h e p l a n t a t i o n s . T h e t r e a t m e n t s a n d t y p e o f f e r t i l i z e r a p p l i e d w a s a s f o l l o w s : A m m o n i u m N i t r a t e ( N H 4 N 0 3 ) a t 0 - ( N 0 ) , 2 0 0 - ( N l ) , 3 0 0 - ( N 2 ) , 4 0 0 - ( N 3 ) k g N / h a T r e b l e S u p e r p h o s p h a t e ( C a ( H 2 P 0 4 ) 2 H 2 0 ) a t 0 - ( P 0 ) a n d 5 0 - ( P ) k g P / h a M u r i a t e o f p o t a s h ( K 2 0 ) a t 0 - ( K O ) a n d 5 0 - ( K ) k g K / h a I n a d d i t i o n , a m i x t u r e o f a l l e s s e n t i a l m a c r o - a n d m i c r o - n u t r i e n t s w a s a p p l i e d t o e a c h s t a n d a s a s e p a r a t e t r e a t m e n t i n c o m b i n a t i o n w i t h 3 0 0 k g N / h a . ( T a b l e 1 0 ) . T h e s e p l o t s w e r e r e p l i c a t e d s e v e n t i m e s g i v i n g a t o t a l o f 1 1 9 p l o t s p e r p l a n t a t i o n . P r e l i m i n a r y f e r t i l i z e r t r i a l s e s t a b l i s h e d b y W e s t e r n F o r e s t P r o d u c t s L t d . i n d i c a t e a p o s s i b l e s y n e r g i s t i c e f f e c t o f P w h e n a p p l i e d t o g e t h e r w i t h N . T h e r e f o r e , a n a d d i t i o n a l s m a l l s c r e e n i n g t r i a l w a s e s t a b l i s h e d w h e r e t h e a m o u n t s o f P w e r e i n c r e a s e d t o 1 0 0 a n d 1 5 0 k g P / h a . T h i s t r i a l w a s l o c a t e d i n s t a n d #2 a l o n g w i t h o n e o f t h e l a r g e r s c r e e n i n g t r i a l s . T h e d e s i g n w a s a c o m p l e t e l y r a n d o m i z e d 4 x 2 ( ( P 0 , P I , P 2 , P 3 ) x ( N O , N ) ) f a c t o r i a l e x p e r i m e n t w i t h f i v e r e p l i c a t i o n s p e r t r e a t m e n t . T h e t r e a t m e n t c o m b i n a t i o n s f o r t h i s t r i a l w e r e : P 0 - 0 k g P / h a , P I - 5 0 k g P / h a , P 2 - 1 0 0 - 6 5 -k g P / h a , P 3 - 1 5 0 k g P / h a , NO - 0 k g N / h a a n d N - 3 0 0 k g N / h a . T h e p l o t s f o r t r e a t m e n t s P I , P I N a n d PON w e r e t a k e n f r o m t h e m a i n f e r t i l i z e r t r i a l o f t h i s s t a n d a n d u s e d t o c o m p l e t e t h e d e s i g n o f t h e s m a l l e r t r i a l . T A B L E 1 0 . R a t e s o f a p p l i c a t i o n n u t r i e n t m i x t u r e . i n k g / h a f o r m a c r o - a n d m i c r o -N U T R I E N T AMOUNT A P P L I E D N U T R I E N T A M 0 U N T A P P L I E D N 3 0 0 F e 1 . 8 0 P 3 8 B 0 . 3 0 K 9 8 Z n 0 . 7 0 C a 5 6 C u 0 . 3 0 Mg 4 8 Mn 0 . 7 5 S 3 1 Mo 0 . 2 0 E a c h t r e a t m e n t c o n s i s t e d o f a m a n u a l a p p l i c a t i o n o f f e r t i l i z e r t o c i r c u l a r 0 . 0 0 8 h a ( 5 m r a d i u s ) p l o t s . I n e a c h p l o t , t w o t r e e s , a c e n t r e ( p l o t c e n t r e ) a n d a n o f f - c e n t r e t r e e , w e r e s e l e c t e d a s s a m p l e t r e e s . E a c h p l o t w a s i d e n t i f i e d b y f a s t e n i n g a n a l u m i n u m t a g w i t h t h e t r e a t m e n t c o d e f o r t h a t p l o t o n t h e c e n t r e t r e e . T h e f e r t i l i z e r w a s a p p l i e d i n t h e l a s t t w o t o t h r e e w e e k s o f A p r i l , 1 9 8 3 . I n t h e l a s t w e e k o f O c t o b e r a n d t h e f i r s t w e e k o f N o v e m b e r , 1 9 8 3 , a l l p l o t s w e r e r e v i s i t e d a n d e a c h t r e e m e a s u r e d f o r f i r s t - y e a r g r o w t h r e s p o n s e s . G r o w t h p a r a m e t e r s m e a s u r e d -66-i n c l u d e t o t a l h e i g h t , 1 9 8 3 l e a d e r l e n g t h , 1 9 8 1 a n d 1 9 8 2 h e i g h t g r o w t h s , a n d c u r r e n t y e a r n e e d l e w e i g h t . F o l i a g e s a m p l e s w e r e a l s o c o l l e c t e d a t t h i s t i m e . S a m p l i n g w a s r e s t r i c t e d t o c u r r e n t y e a r s f o l i a g e f r o m t h e u p p e r t h i r d a n d f o u r t h w h o r l s o f t h e c r o w n . S a m p l e s w e r e p l a c e d i n p a p e r b a g s ( p l a s t i c b a g s w e r e u s e d t o s t o r e s a m p l e s w h i c h w e r e a n a l y z e d f o r m i c r o - n u t r i e n t s ) a n d b u l k e d b y p l o t . I t i s r e a l i z e d t h a t o n e g r o w i n g s e a s o n ( t h e t i m e a v a i l a b l e f o r t h i s s t u d y ) may n o t b e s u f f i c i e n t f o r h e i g h t g r o w t h r e s p o n s e s t o b e c o m e a p p a r e n t . H o w e v e r , t h e s e s t a n d s a r e t e n t a t i v e l y s c h e d u l e d f o r r e m e a s u r e m e n t a t t h e e n d o f t h e t h i r d g r o w i n g s e a s o n . A l t h o u g h t h i s t h e s i s w a s m a i n l y d e s i g n e d t o s t u d y t h e e f f e c t s o f f e r t i l i z a t i o n o n s p r u c e , m a n y p l o t s h a d n a t u r a l l y o c c u r r i n g c e d a r a n d h e m l o c k . S i n c e t h e s e s i t e s a r e now c o n s i d e r e d t o b e b e t t e r s u i t e d t o t h e s e s p e c i e s t h a n s p r u c e , w h e n e v e r a s u i t a b l e s p e c i m e n b e t w e e n 1 . 5 m a n d 2 . 5 m i n h e i g h t o c c u r r e d w i t h i n a p l o t , f o l i a g e s a m p l e s w e r e c o l l e c t e d f o r a n a l y s i s . On t h e s e s p e c i e s , s a m p l i n g w a s r e s t r i c t e d t o t h e t e r m i n a l s h o o t s o f t h e t o p f o u r l a t e r a l b r a n c h e s . L a b o r a t o r y A n a l y s i s A l l s a m p l e s w e r e d r i e d f o r 2 4 h o u r s a t 7 0 ° C i n f o r c e d - d r a f t o v e n s . A f t e r d r y i n g , a l l n e e d l e s w e r e r e m o v e d f r o m t h e t w i g s . T h e m e a n o v e n - d r y w e i g h t o f 1 0 0 n e e d l e s w a s t h e n d e t e r m i n e d o n t h r e e l o t s o f 1 0 0 w h o l e n e e d l e s f o r e a c h s a m p l e . T h e r e m a i n i n g n e e d l e s w e r e g r o u n d i n a s m a l l -67-e l e c t r i c c o f f e e g r i n d e r a n d s t o r e d i n s n a p - c a p p l a s t i c v i a l s f o r s u b s e q u e n t c h e m i c a l a n a l y s i s . A l l s a m p l e s w e r e a n a l y z e d f o r N , P , K , C a a n d M g . I n a d d i t i o n , t r e a t m e n t s NO ( c o n t r o l ) , N l ( 2 0 0 k g N / h a ) , N2 ( 3 0 0 k g N / h a ) , N 3 ( 4 0 0 k g N / h a ) a n d N P K T ( m a c r o - p l u s m i c r o - n u t r i e n t m i x t u r e ) w e r e a l s o a n a l y z e d f o r t o t a l S , B , C u , Z n , Mn a n d a c t i v e F e . T h e m i c r o - n u t r i e n t a n a l y s i s w a s d o n e b y N o r w e s t - P r i v a P l a n t L a b o r a t o r i e s I n c . A l l o t h e r c h e m i c a l a n a l y s i s w a s d o n e a t U B C . N i t r o g e n a n d p h o s p h o r u s c o n c e n t r a t i o n s w e r e d e t e r m i n e d b y a s t a n d a r d s e m i m i c r o - K j e l d a h l d i g e s t i o n , t h e n a n a l y z e d c o l o r i m e t r i c a l l y w i t h a T e c h n i c o n a u t o a n a l y z e r . B a s e e l e m e n t s ( K , C a a n d M g ) w e r e d e t e r m i n e d b y a t o m i c a b s o r p t i o n s p e c t r o p h o t o m e t r y a f t e r i n i t i a l l y d r y a s h i n g 1 g o f s a m p l e a n d d i s s o l v i n g i t i n 2 0 % H C 1 s o l u t i o n . T o t a l S w a s d e t e r m i n e d u s i n g a L e c o S u l f u r a n a l y z e r . I n t e r p r e t a t i o n s o f t h e f o l i a r a n a l y s i s w i t h r e s p e c t t o c h a n g e s i n n e e d l e n u t r i e n t c o n c e n t r a t i o n s a n d c o n t e n t , a n d n e e d l e w e i g h t w e r e b a s e d o n t h e g r a p h i c a l a p p r o a c h d e s c r i b e d i n t h e L i t e r a t u r e R e v i e w . S t a t i s t i c a l A n a l y s i s F o r t h e p u r p o s e o f t h i s s t u d y , a l l f i v e s t a n d s h a v e . b e e n c o m b i n e d f o r a n a l y s i s w i t h e a c h s t a n d b e i n g t r e a t e d a s a s e p a r a t e b l o c k . I n d i v i d u a l a n a l y s i s o f e a c h s t a n d i s g i v e n i n A p p e n d i x I . A l l a n a l y s e s o f v a r i a n c e w e r e p e r f o r m e d u s i n g U . B . C . ' s c o m p u t e r p r o g r a m G E N L I N . A t w o - w a y a n a l y s i s o f v a r i a n c e f o l l o w e d b y a S t u d e n t - N e w m a n s - K e u l s 1 m u l t i p l e r a n g e t e s t w a s p e r f o r m e d o n a l l t r e a t m e n t s . A l l t r e a t m e n t s , e x c e p t - 6 8 -N P K T , w e r e a l s o s u b j e c t e d t o a 4 x 2 x 2 f a c t o r i a l a n a l y s e s o f v a r i a n c e . C o v a r i a n t a n a l y s i s , u s i n g t h e 1 9 8 2 h e i g h t i n c r e m e n t a s t h e c o v a r i a t e , w a s u s e d i n a l l a n a l y s i s c o n c e r n i n g t h e 1 9 8 3 l e a d e r g r o w t h . B e c a u s e o f t h e l i m i t e d s a m p l e s i z e s , S t u d e n t - t t e s t s w e r e u s e d f o r t h e c o m p a r i s o n a n d a n a l y s e s o f h e m l o c k a n d c e d a r d a t a . T h e r e w a s c o n s i d e r a b l e h e t e r o g e n e i t y a m o n g s t t h e v a r i o u s t r e a t m e n t c e l l v a r i a n c e s a n d t h e r e f o r e i t w a s n e c e s s a r y t o a p p l y a s e r i e s o f t r a n s f o r m a t i o n s t o t h e d a t a b e f o r e a n a l y s i s . S i n c e e a c h o f t h e v a r i a b l e s u n d e r s t u d y r e a c t e d d i f f e r e n t l y t o t h e v a r i o u s t r e a t m e n t s , d i f f e r e n t t r a n s f o r m a t i o n s w e r e u s e d f o r c e r t a i n v a r i a b l e s . I n a l l c a s e s , e x c e p t f o r s p r u c e K c o n t e n t , w h i c h w a s t r a n s f o r m e d by a s q u a r e r o o t t r a n s f o r m a t i o n , l o g a r i t h m i c t r a n s f o r m a t i o n s w e r e u s e d . S p r u c e N c o n t e n t , 1 9 8 3 l e a d e r g r o w t h , a n d c e d a r N a n d P c o n c e n t r a t i o n s w e r e t r a n s f o r m e d b y l o g ( x ) , s p r u c e n u t r i e n t c o n c e n t r a t i o n s b y l o g ( x + 1 ) , a n d s p r u c e P , C a a n d Mg c o n t e n t a n d h e m l o c k N a n d P c o n c e n t r a t i o n b y l o g [ l o g ( x + 1 ) ] . E v e n a f t e r t h e t r a n s f o r m a t i o n s o f t h e s p r u c e n e e d l e n u t r i e n t c o n c e n t r a t i o n s t o l o g ( x + 1 ) s o m e h e t e r o g e n e i t y b e t w e e n v a r i a n c e s s t i l l e x i s t e d . T h e s e d i f f e r e n c e s a p p e a r t o be m i n i m a l a n d i t i s d o u b t f u l t h a t t h e y w i l l h a v e a n y i n f l u e n c e o n t h e s t a t i s t i c a l o u t c o m e . C o m p a r i s o n s o f t h e a n a l y s i s o f v a r i a n c e o f t r a n s f o r m e d a n d u n t r a n s f o r m e d d a t a i n d i c a t e d t h a t t h e t r a n s f o r m a t i o n s r e s u l t e d i n o n l y a f e w m i n o r c h a n g e s i n t h e s i g n i f i c a n c e o f t r e a t m e n t m e a n d i f f e r e n c e s . A l l d a t a t h r o u g h o u t t h e t h e s i s a r e p r e s e n t e d i n t h e i r o r i g i n a l v a l u e s . - 6 9 -R E S U L T S & D I S C U S S I O N T h e a n a l y s i s o f v a r i a n c e i n d i c a t e d t h a t f e r t i l i z a t i o n h a d a h i g h l y s i g n i f i c a n t ( p = . 0 1 ) e f f e c t o n f i r s t y e a r h e i g h t g r o w t h , n e e d l e w e i g h t , a n d n e e d l e n u t r i e n t c o n c e n t r a t i o n a n d c o n t e n t . N o t o n l y w e r e t h e m a i n e f f e c t s o f N , P a n d K h i g h l y s i g n i f i c a n t , b u t t h e r e w e r e a l s o a n u m b e r o f h i g h l y s i g n i f i c a n t i n t e r a c t i o n s ( T a b l e 1 1 ) . F o r t h e p u r p o s e o f p r e s e n t a t i o n , a l l f i v e s t a n d s w e r e c o m b i n e d f o r t h e a n a l y s i s o f v a r i a n c e a n d g r a p h i c a l i n t e r p r e t a t i o n s o f f o l i a r a n a l y s i s . T h e a n a l y s i s o f i n d i v i d u a l s t a n d s a r e g i v e n i n A p p e n d i x I . E f f e c t s o n N e e d l e W e i g h t a n d L e a d e r G r o w t h F e r t i l i z a t i o n s i g n i f i c a n t l y i n c r e a s e d b o t h t h e c u r r e n t y e a r ' s n e e d l e d r y - w e i g h t a n d t h e 1 9 8 3 l e a d e r g r o w t h ( T a b l e 1 1 ) . A l t h o u g h N a l o n e h a d a s i g n i f i c a n t i n f l u e n c e ( p = . 0 5 ) o n b o t h n e e d l e w e i g h t a n d l e a d e r g r o w t h , t h e r e w a s a h i g h l y s i g n i f i c a n t ( p = . 0 1 ) N x P i n t e r a c t i o n ( F i g u r e 1 2 ) . P h a d a s t r o n g s y n e r g i s t i c e f f e c t o n b o t h n e e d l e w e i g h t a n d l e a d e r g r o w t h w h e n a d d e d t o g e t h e r w i t h N ( F i g u r e s 1 0 a n d 1 1 ) . N a l o n e o r i n c o m b i n a t i o n w i t h K r e s u l t e d i n o n l y a 1 0 % i n c r e a s e i n n e e d l e w e i g h t a n d a 2 5 t o 3 0 % i n c r e a s e i n t h e 1 9 8 3 l e a d e r g r o w t h o v e r t h a t o f t h e c o n t r o l . H o w e v e r , w h e n T A B L E 1 1 . A n a l y s i s o f v a r i a n c e o f f i r s t y e a r l e a d e r g r o w t h , n e e d l e d r y - w e i g h t , a n d n e e d l e n u t r i e n t c o n c e n t r a t i o n a n d c o n t e n t . T R E A T M E N T E F F E C T S S O U R C E OF V A R I A T I O N : N P K NP NK P K NPK B L O C K D E G R E E S OF F R E E D O M : 3 1 1 3 3 1 3 4 N e e d l e w e i g h t 1 9 8 3 L e a d e r g r o w t h N u t r i e n t c o n c e n t r a t i o n N P K C a Mg N u t r i e n t c o n t e n t N P K C a Mg ( + ) * * ( + ) * * + ) * * ( + ) * * — + ) * * ( + ) * - ( + ) * * -_ ) * * - ( + ) * * + ) * - ( + ) * * — — ( _ ) * * + ) * * ( + ) * * + ) * * ( + ) * * -_ ) * * ( + ) * * ( + ) * * + ) * * ( + ) * * ( + ) * * + ) * * ( + ) * * ( _ ) * * * * _ _ _ * * ** _ _ _ _ ** _ _ ** ** ** — _ ** _ _ _ _ * * * _ _ _ * * * * _ _ _ * * _ _ _ _ * * ** ** _ _ ** #* _ _ _ ** ** _ _ _ ** * S i g n i f i c a n t a t 0 . 0 5 l e v e l . * * S i g n i f i c a n t a t 0 . 0 1 l e v e l . - S i g n i f i e s n o n - s i g n i f i c a n t . - 7 1 -a d d e d t o g e t h e r w i t h P o r P p l u s K , n e e d l e d r y - w e i g h t i n c r e a s e d b y 4 0 t o 4 1 % a n d l e a d e r g r o w t h b y 7 8 t o 8 3 % ( T a b l e 1 2 ) . W h i l e a r e l a t i v e i n c r e a s e i n g r o w t h o f 8 3 % s e e m s i m p r e s s i v e , i t s h o u l d b e k e p t i n m i n d t h a t t h e 1 9 8 3 a n n u a l h e i g h t i n c r e m e n t o f t h e s e p l a n t a t i o n s o n l y a v e r a g e d 1 0 . 0 c m , t h u s , i n a b s o l u t e t e r m s , a n 8 3 % i n c r e a s e c o r r e s p o n d s t o a n a n n u a l i n c r e m e n t o f o n l y 1 8 . 3 c m . T h i s h o w e v e r , w a s o n l y t h e f i r s t - y e a r r e s p o n s e . M a n y r e s e a r c h e r s h a v e s h o w n t h a t g r o w t h r e s p o n s e s i n t h e y e a r o f f e r t i l i z a t i o n a r e o f t e n m i n i m a l a n d t h a t s i g n i f i c a n t g a i n s f r o m f e r t i l i z a t i o n t y p i c a l l y o n l y b e c o m e a p p a r e n t a f t e r t h e f i r s t g r o w i n g s e a s o n ( A t k i n s o n , 1 9 7 5 ; D i c k s o n a n d S a v i l l , 1 9 7 4 ; F a g e r s t r o m a n d L o h m , 1 9 7 7 ) . P r e l i m i n a r y f e r t i l i z e r t r i a l s e s t a b l i s h e d b y W e s t e r n F o r e s t P r o d u c t s L t d . i n s i m i l a r S i t k a s p r u c e p l a n t a t i o n s h a v e a l s o s h o w n g r e a t e r r e s p o n s e s i n t h e s e c o n d a n d t h i r d y e a r f r o m f e r t i l i z a t i o n a s c o m p a r e d t o t h e f i r s t y e a r g r o w t h r e s p o n s e s . I n c r e a s i n g t h e r a t e s o f N a p p l i c a t i o n f r o m 2 0 0 t o 4 0 0 k g N / h a t e n d e d t o r e s u l t i n a p r o g r e s s i v e d e c l i n e i n b o t h n e e d l e w e i g h t a n d l e a d e r g r o w t h r e s p o n s e s . W h i l e t h e e f f e c t s o f i n c r e a s i n g N v a r i e d b e t w e e n s t a n d s ( T a b l e 1 2 ) , p a r t i c u l a r l y f o r l e a d e r g r o w t h , t h e d e c l i n e i s r e a d i l y ; e v i d e n t i n F i g u r e 12 w h i c h i l l u s t r a t e s t h e e f f e c t o f t h e N x P i n t e r a c t i o n o n g r o w t h . T h i s d e c l i n e w a s s i g n i f i c a n t f o r n e e d l e w e i g h t o n l y w h e n N a n d P w e r e a d d e d t o g e t h e r a n d i t w a s n o t s i g n i f i c a n t f o r l e a d e r g r o w t h . T h e d e p r e s s i o n o f g r o w t h a t t h e 3 0 0 a n d 4 0 0 k g N / h a r a t e s a p p e a r s t o b e l a r g e l y d u e t o t h e r e s u l t i n g h i g h f o l i a r -72-in a> •o 0) a> c O O X UJ _ i Q UJ UJ _eo •60 •40 _ 2 0 MOP NOPK NO NOK N3K N2 N3 NIK Nl 'N2k~N3P"N2P N3PK N2f5K~NIPK NIP NPKT TREATMENTS FIGURE 10. N e e d l e w e i g h t r e s p o n s e . T r e a t m e n t s c o n n e c t e d by t h e same l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p= .01 . V e r t i c a l b a r s + 1 SD. _20 _I6 I X t— ^ -'2 O or <s> _ D: UJ Q _e < UJ _4 MOP NOPK NO NOK N2K N3K N3 NIK Nl N2 N2P N3PK NIPK N3P N2PK NPKT NIP TREATMENTS FIGURE 11. L e a d e r g r o w t h r e s p o n s e . T r e a t m e n t s c o n n e c t e d by t h e same l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p= .01 . TABLE 12: Percent change from control in needle dry-weight and 1983 leader growth for each stand. OVEN-DRY NEEDLE WEIGHT 1983 LEADER GROWTH TREATMENT STAND STAND ALL STANDS ALL STANDS 1 2 3 4 5 COMBINED 1 2 3 4 5 COMBINED NOK 13 0 4 -15 18 4 16 -13 9 -36 35 4 NOP -2 1 -6 2 -17 -4 7 -38 -4 -16 3 -16 NOPK 10 2 -8 1 -6 -1 3 -2 -14 -8 5 -5 Average 7 1 -3 -4 -2 0 9 -18 -3 -20 14 -5 Nl 28 12 6 -3 24 13 46 14 45 5 45 31 N2 18 -6 -1 14 10 6 46 -5 22 44 43 31 N3 .8 -5 9 27 21 11 40 -5 18 31 61 28 Average 18 0 5 13 18 10 44 1 29 27 50 30 NIK 20 5 2 21 17 12 79 -4 30 16 35 30 N2K 15 9 11 26 11 14 47 -7 29 9 35 22 N3K 24 -7 -5 16 0 5 56 -6 23 7 44 23 Average 20 2 3 21 9 10 61 -6 27 11 38 25 NIP 84 46 28 54 39 49 116 85 68 82 138 96 N2P 43 37 29 37 38 36 72 49 68 74 99 72 N3P 46 25 39 40 21 34 121 40 102 65 77 81 Average 58 36 32 44 33 40 103 58 79 74 105 83 N1PK 56 43 43 56 41 47 102 30 96 68 79 75 N2PK 62 33 29 40 38 39 122 40 104 73 82 84 N3PK 46 24 31 24 59 37 110 43 67 42 124 75 Average 55 33 34 40 46 41 111 38 89 61 95 78 NPKT 70 66 " 73 66 51 65 88 87 93 81 145 95 -74-50 kg P/ha '0 kg P/ha 200 300 400 kg N / h a FIGURE 12. 550 kg P/ha 0 kg P/ha 200 300 400 kg N/ha N x P i n t e r a c t i o n e f f e c t s on 1983 l e a d e r g r o w t h and n e e d l e w e i g h t . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p=.05. - 7 5 -N c o n c e n t r a t i o n s . T h e m e a n f o l i a r N c o n c e n t r a t i o n a t t h e s e r a t e s w a s 3 . 9 % a n d 4 . 1 % , r e s p e c t i v e l y , a s c o m p a r e d t o 3 . 2 % f o r t h e 2 0 0 k g N / h a t r e a t m e n t s . E b e l l ( 1 9 7 2 ) f o u n d t h a t s t e m g r o w t h o f a 2 2 y e a r o l d D o u g l a s - f i r s t a n d b e n e f i t e d f r o m i n c r e a s i n g f o l i a r N l e v e l s u p t o a b o u t 2% b u t w a s a d v e r s e l y a f f e c t e d b y f o l i a r N l e v e l s a b o v e 3 % . S i m i l a r l y , B r o c k l e y ( 1 9 8 1 ) n o t e d a d v e r s e e f f e c t s o n t h e g r o w t h o f D o u g l a s - f i r s e e d l i n g s w h e n f o l i a r n u t r i e n t l e v e l s i n c r e a s e d t o 4 a n d 5 % . A v a l u e o f a b o u t 2 . 0 t o 2 . 5 % f o l i a r N a l s o s e e m s t o b e t h e u p p e r t o l e r a n c e l i m i t f o r o t h e r s p e c i e s s u c h a s P i c e a a b i e s a n d P i n u s n i g r a ( T a m m , 1 9 6 8 , 1 9 7 4 ; M i l l e r e t a l . , 1 9 8 1 ) . T h e s e f i n d i n g s o f E b e l l ( 1 9 7 2 ) a n d o t h e r s s u g g e s t t h a t e v e n a t t h e l o w e s t a p p l i c a t i o n r a t e o f 2 0 0 k g N / h a , f o l i a r N c o n c e n t r a t i o n s m a y h a v e b e e n h i g h e n o u g h t o a d v e r s e l y i n f l u e n c e b o t h n e e d l e a n d l e a d e r g r o w t h . A f t e r a d j u s t i n g f o r d i f f e r e n c e s i n i n i t i a l g r o w t h , t h e 1 9 8 3 l e a d e r g r o w t h o f t h e s a m p l e d h e m l o c k w a s s i g n i f i c a n t l y g r e a t e r t h a n t h e s p r u c e o n l y i n t h o s e N t r e a t m e n t s w h e r e t h e m e a n f o l i a r N c o n c e n t r a t i o n w a s l e s s t h a n 3 . 0 % ( T a b l e s 1 2 a n d 1 4 ) . T h e r e w a s a l s o a w e a k , b u t h i g h l y s i g n i f i c a n t n e g a t i v e c o r r e l a t i o n b e t w e e n N a n d h e m l o c k l e a d e r g r o w t h ( r = - . 5 2 4 7 ) , b u t n o t b e t w e e n N a n d s p r u c e l e a d e r g r o w t h . T h e f a c t t h a t N w a s n o t c o r r e l a t e d t o s p r u c e l e a d e r g r o w t h m a y b e d u e t o i t s d e t e r m i n a t e g r o w t h n a t u r e . A l t h o u g h t h e h i g h N c o n c e n t r a t i o n s may h a v e h a d a n i n i t i a l d e t r i m e n t a l e f f e c t o n g r o w t h , i t i s p o s s i b l e t h a t t h e s e l o s s e s m a y l a r g e l y b e c o m p e n s a t e d b y p r o l o n g e d g r o w t h r e s p o n s e s f r o m i n t e r n a l r e t r a n s l o c a t i o n o f N ( M i l l e r , 1 9 8 1 ) . - 7 6 -I n c r e a s i n g t h e a m o u n t s o f P t o 1 0 0 a n d 1 5 0 k g / h a h a d n o e f f e c t i n c o u n t e r a c t i n g t h e a d v e r s e e f f e c t s o f t h e h i g h f o l i a r N c o n c e n t r a t i o n s o n n e e d l e w e i g h t o r l e a d e r g r o w t h . T h e a d d i t i o n o f t h e c o m p l e t e n u t r i e n t m i x t u r e ( N P K T ) h o w e v e r , r e s u l t e d i n a s i g n i f i c a n t ( p = . 0 1 ) i n c r e a s e i n n e e d l e w e i g h t o v e r a l l o t h e r t r e a t m e n t s , e x c e p t N I P a n d N 1 P K ( F i g u r e 1 0 ) a n d a p p e a r s t o h a v e h a d s o m e w h a t o f a p o s i t i v e e f f e c t o n l e a d e r g r o w t h . U n f o r t u n a t e l y , b e c a u s e o f t h e n a t u r e o f t h i s t r e a t m e n t , i t i s n o t p o s s i b l e t o s a y w h i c h n u t r i e n t o r n u t r i e n t s a r e c a u s i n g t h e a d d i t i o n a l e f f e c t . P r e s u m a b l y m u c h o f t h e b e n e f i c i a l e f f e c t c a n b e a t t r i b u t e d s i m p l y t o a m o r e b a l a n c e d s u p p l y o f n u t r i e n t s . G r o w t h r e s p o n s e o f S c o t s p i n e g r o w i n g o n d e e p p e a t s a r e f r e q u e n t l y i m p r o v e d w h e n m i c r o - n u t r i e n t s w e r e a d d e d t o h e a v i l y N P K f e r t i l i z e d t r e e s ( V e i j a l a i n e n , 1 9 8 1 ) . O f n o t e i n t h e N P K T t r e a t m e n t s i n t h e p r e s e n t s t u d y , i s t h e p o s s i b l e b e n e f i c i a l e f f e c t s o f t h e a d d i t i o n a l K . T h e K c o n t e n t o f t h i s t r e a t m e n t w a s e q u i v a l e n t t o 9 8 k g K / h a ( T a b l e 1 0 ) a s c o m p a r e d t o 5 0 k g K / h a f o r a l l o t h e r t r e a t m e n t s w h e r e K w a s a d d e d . A s a r e s u l t , b o t h t h e K c o n t e n t a n d c o n c e n t r a t i o n w e r e s i g n i f i c a n t l y h i g h e r ( p = . 0 5 ) t h a n i n o t h e r r e s p o n s i v e t r e a t m e n t s ( T a b l e 1 6 ) . B e s i d e s K , a d d i t i o n a l b e n e f i t s f r o m t h e N P K T t r e a t m e n t may h a v e a l s o b e e n d e r i v e d f r o m t h e a d d i t i o n o f Mg a n d / o r S ( s e e s u b s e q u e n t d i s c u s s i o n s ) . A l t h o u g h P a n d K a p p e a r t o b e d e f i c i e n t o n t h e s e s i t e s , t h e a d d i t i o n o f e i t h e r n u t r i e n t a l o n e o r i n c o m b i n a t i o n w i t h o u t N h a d n o s i g n i f i c a n t i n f l u e n c e o n g r o w t h . - 7 7 -I n f a c t , t h e r e w a s a t e n d e n c y f o r t h e s e t r e a t m e n t s t o d e p r e s s g r o w t h ( T a b l e 1 2 ) . P r e s u m a b l y t h e l a c k o f r e s p o n s e i s d u e t o t h e l i m i t i n g e f f e c t o f N . C a r e y ( 1 9 7 7 ) n o t e d t h a t c h e c k e d S i t k a s p r u c e i n B r i t a i n d i d n o t r e s p o n d t o P o r P p l u s K f e r t i l i z a t i o n w h e n N w a s a l s o l i m i t i n g . T h i s h o w e v e r i s i n c o n t r a s t t o D i c k s o n a n d S a v i l l ( 1 9 7 4 ) w h o n o t e d S i t k a s p r u c e w o u l d o f t e n r e s p o n d f a v o u r a b l y t o P f e r t i l i z a t i o n w h e n b o t h P a n d N w e r e l i m i t i n g . T h e y a t t r i b u t e d t h e r e s p o n s e t o t h e f a c t t h a t P f e r t i l i z a t i o n o f t e n i n c r e a s e s t h e a v a i l a b i l i t y o f N t o t h e t r e e s . A l t h o u g h n e e d l e w e i g h t a n d l e a d e r g r o w t h w e r e f o u n d t o b e s i g n i f i c a n t l y c o r r e l a t e d , t h e r e l a t i o n s h i p w a s w e a k ( r v a l u e s r a n g e d f r o m . 4 4 7 2 t o . 5 2 9 2 ) . T h i s w e a k r e l a t i o n s h i p may h a v e r e s u l t e d b e c a u s e o n l y f i r s t - y e a r g r o w t h r e s p o n s e s w e r e b e i n g c o n s i d e r e d . A s m e n t i o n e d p r e v i o u s l y , t h e d e t e r m i n a t e g r o w t h n a t u r e o f s p r u c e c a n s i g n i f i c a n t l y i n f l u e n c e g r o w t h i n a n y o n e y e a r , o b s c u r i n g a n y r e l a t i o n s h i p w h i c h may e x i s t . T h i s c o n t r a s t e d w i t h T i m m e r a n d S t o n e ( 1 9 7 8 ) w h o f o u n d t h a t c h a n g e s i n n e e d l e w e i g h t o f A b i e s  b a l s a m e a a c c o u n t e d f o r 6 5 t o 7 3 % o f t h e t o t a l v a r i a t i o n i n t h e f i r s t s e a s o n s s h o o t g r o w t h . D e s p i t e t h e w e a k r e l a t i o n s h i p s f o u n d i n t h e P o r t M c N e i l l s t u d y , t h e r e a p p e a r e d t o b e a g e n e r a l t r e n d o f i n c r e a s i n g l e a d e r g r o w t h w i t h i n c r e a s i n g n e e d l e w e i g h t . T h i s b e c o m e s e v i d e n t i f o n l y p l o t m e a n s w e r e c o n s i d e r e d a s t h e o v e r a l l r v a l u e i n c r e a s e d t o . 7 5 2 9 w i t h a r a n g e o f . 8 6 7 3 t o . 9 1 8 2 f o r t h e i n d i v i d u a l s t a n d s . - 7 8 -P a t t e r n s o f s h o o t r e s p o n s e f o r h e m l o c k w e r e v e r y s i m i l a r t o t h a t o f s p r u c e , a l t h o u g h s o m e w h a t g r e a t e r ( T a b l e 1 3 ) . T h e a d d i t i o n o f N o r N p l u s K a l o n e h a d a h i g h l y s i g n i f i c a n t , p o s i t i v e e f f e c t o n g r o w t h . A s i n s p r u c e h o w e v e r , t h e a d d i t i o n o f P w i t h N o r N p l u s K r e s u l t e d i n a h i g h l y s i g n i f i c a n t s y n e r g i s t i c r e s p o n s e o v e r N a l o n e , w h e r e a s , t h e a d d i t i o n o f P o r P p l u s K w i t h o u t N h a d n o s i g n i f i c a n t i n f l u e n c e o n g r o w t h . I n c r e a s i n g t h e r a t e s o f N a p p l i c a t i o n f r o m 2 0 0 t o 4 0 0 k g / h a a l s o r e s u l t e d i n a p r o g r e s s i v e d e c l i n e i n t h e r e s p o n s e o f t h i s s p e c i e s . I n i t i a l r e s u l t s f r o m r e c e n t f e r t i l i z e r t r i a l s e s t a b l i s h e d o n s i m i l a r s i t e s b y B r i t i s h C o l u m b i a F o r e s t P r o d u c t s L t d . ( B C F P ) , h a v e a l s o f o u n d h e m l o c k t o b e h i g h l y r e s p o n s i v e t o f e r t i l i z a t i o n w i t h a m m o n i u m n i t r a t e ( B C F P , p e r s o n a l c o r r e s p o n d e n c e ) . T h e f a c t t h a t h e m l o c k a p p e a r s t o b e r e s p o n s i v e o n t h e s e s i t e s i s e n c o u r a g i n g s i n c e n u m e r o u s o t h e r f e r t i l i z e r t r i a l s h a v e s h o w n t h e s p e c i e s t o b e h i g h l y e r r a t i c i n i t s a b i l i t y t o r e s p o n d t o f e r t i l i z a t i o n ( D e B e l l e t a l . , 1 9 7 5 ; W e b s t e r e t a l . , 1 9 7 6 ) . G i l l a n d L a v e n d e r ( 1 9 8 3 a ) h a v e r e c e n t l y s h o w n t h a t u r e a c a n n e g a t i v e l y i n f l u e n c e m y c o r r h i z a l d e v e l o p m e n t a n d t h u s may l i m i t t h e t r e e s a b i l i t y t o r e s p o n d t o t h i s f o r m o f n i t r o g e n . S i n c e a m m o n i u m n i t r a t e : w a s u s e d i n t h e p r e s e n t s t u d y , s u c h a d v e r s e e f f e c t s w o u l d n o t b e e x p e c t e d , a l t h o u g h , f e r t i l i z e r t r i a l s e l s e w h e r e u s i n g a m m o n i u m n i t r a t e h a v e l a r g e l y p r o v e n t o b e i n c o n c l u s i v e ( W e b s t e r e t a l . , 1 9 7 6 ; R a d w a n a n d D e B e l l , 1 9 8 0 ) . T h e s t r o n g s y n e r g i s t i c e f f e c t o f P o n t h e s e s i t e s s u g g e s t t h a t P i s l i m i t i n g . T h e r e i s i n c r e a s i n g e v i d e n c e - 7 9 -T A B L E 1 3 . 1 9 8 3 L e a d e r g r o w t h r e s p o n s e s o f s a m p l e d h e m l o c k . T r e a t m e n t s c o n n e c t e d by t h e s a m e l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 . T R E A T M E N T L E A D E R % C H A N G E S T A N D A R D NUMBER OF GROWTH ( c m ) FROM C O N T R O L D E V I A T I O N S A M P L E S NOK 1 5 . 6 - 1 1 6 . 4 9 9 17 NO 1 7 . 5 - 7 . 1 3 8 1 8 NOPK 1 9 . A 11 9 . 7 3 5 12 NOP 2 0 . 1 1 5 6 . 3 7 9 1 5 N3 2 5 . 3 4 5 1 2 . 5 7 2 1 3 N3K 2 6 . 5 5 1 1 3 . 4 2 8 1 6 N2K 2 8 . 0 6 0 1 0 . 1 1 6 1 2 N2 2 9 . 3 6 7 1 2 . 1 7 2 11 N 3 P K * 3 2 . 1 8 3 1 2 . 3 6 5 11 N I K * 3 5 . 0 1 0 0 1 2 . 1 2 5 1 3 N l * 3 5 . 1 1 0 1 1 0 . 6 7 3 9 N 3 P * 3 8 . 9 1 2 2 1 0 . 8 4 7 1 1 N 2 P K * • 4 0 . 0 1 2 9 1 2 . 5 5 2 11 N 1 P K * 4 2 . 5 1 4 3 1 1 . 6 4 9 1 9 N 2 P * 4 6 . 7 1 6 7 1 3 . 2 6 9 1 5 N P K T * 5 3 . 4 2 0 5 1 2 . 1 0 4 17 N I P * 5 3 . 7 2 0 7 1 0 . 8 6 3 16 * T r e a t m e n t s i n w h i c h h e m l o c k h a d a s i g n i f i c a n t l y g r e a t e r r e s p o n s e ( p = . 0 1 ) t h a n s p r u c e . - 8 0 -i n d i c a t i n g t h a t m a n y c o a s t a l s i t e s a r e P d e f i c i e n t . I t h a s b e e n s u g g e s t e d t h a t s u c h d e f i c i e n c i e s may a c c o u n t f o r s o m e o f t h e e r r a t i c f e r t i l i z e r r e s p o n s e s e x h i b i t e d by h e m l o c k ( R a d w a n a n d S h u m w a y , 1 9 8 3 ; G i l l a n d L a v e n d e r , 1 9 8 3 b ) . E f f e c t s o n F o l i a r N i t r o g e n M e a n f o l i a r N c o n c e n t r a t i o n s o f t h e S i t k a s p r u c e i n t h e c o n t r o l p l o t s w a s o n l y 0 . 7 9 % ( T a b l e 1 4 ) w h i c h s u g g e s t s t h a t t h e s p r u c e i n t h e s e s t a n d s a r e s u f f e r i n g f r o m a s e v e r e N d e f i c i e n c y . I n c o n t r a s t , m o r e v i g o u r o u s s p r u c e f r o m t h e H A - p h a s e h a d a m e a n f o l i a r N c o n c e n t r a t i o n o f 1 . 2 9 % w h i c h , a l t h o u g h c o n s i d e r a b l y h i g h e r t h a n t h a t o f t h e C H - p h a s e , i s a l s o w e l l b e l o w , w h a t i s c o n s i d e r e d t o b e o p t i m u m f o r t h e s p e c i e s ( T a b l e 1 ) . F e r t i l i z a t i o n w i t h N r e s u l t e d i n a h i g h l y s i g n i f i c a n t i n c r e a s e i n f o l i a r N c o n c e n t r a t i o n ( T a b l e 1 4 ) . T h e r e w a s a l s o a h i g h l y s i g n i f i c a n t N x K i n t e r a c t i o n . T h e e f f e c t s o f t h i s i n t e r a c t i o n o n N c o n c e n t r a t i o n s h o w e v e r , w a s r e l a t i v e l y m i n o r c o m p a r e d t o t h e m a i n e f f e c t o f N a n d d o e s n o t i n f l u e n c e t h e i n t e r p r e t a t i o n s . I n c r e a s i n g r a t e s o f N a p p l i c a t i o n r e s u l t e d i n a c o r r e s p o n d i n g s i g n i f i c a n t i n c r e a s e i n m e a n f o l i a r N c o n c e n t r a t i o n s t o 3 . 1 9 % , 3 . 9 4 % a n d 4 . 0 9 % f o r ; t h e 2 0 0 , 3 0 0 a n d 4 0 0 k g / h a a p p l i c a t i o n r a t e s , r e s p e c t i v e l y . T h e h i g h N c o n c e n t r a t i o n s e x p e r i e n c e d i n t h i s s t u d y a r e u n u s u a l a n d t h e r e a r e f e w p u b l i s h e d e x a m p l e s f r o m o t h e r f e r t i l i z e r t r i a l s w h e r e s i m i l a r h i g h c o n c e n t r a t i o n s w e r e e x p e r i e n c e d , i n f a c t , f o l i a r c o n c e n t r a t i o n s e x c e e d i n g 2 . 5 % a p p e a r t o b e r a r e . S o m e n o t a b l e e x c e p t i o n s h o w e v e r , a r e t h e T A B L E 1 4 . soruce a S L S o r k e ! ! Y P e H i e a C ? , B p a r l 3 0 n 9 ° f raean f 0 l i a r " " " c e n t r a t i o n s (2 o v e n - d r y w e i g h t ) for aSPeUnoc ^n . t i c^ ly l i f fer lnTT^oS!" ' " . " * " " " >' l ' « . r W I T H I N S P E C I E S COMPARISON SPRUCE HEMLOCK CEDAR NO NOK NOP NOPK N I P N l NIK N1PK NPKT N2K N3K N2 N2PK N3P N2P N3PK N3 -TREATMENT-NOP NOK NOPK NO NIP NPKT N1PK N2P NIK N2PK N l N3P N3PK N2K N2 N3K N3 NOP NOK NOPK NO N l N1PK NPKT N I P N2 NIK N2PK N2P N2K N3K N3P N3PK N3 TREATMENT NO N l N2 N3 NOP N I P N2P N3P NOK NIK N2K N3K NOPK N1PK N2PK N3PK NPKT • B E T W E E N S P E C I E S COMPARISON S P R U C E HEMLOCK CEDAR 0 . 7 9 a 3 . 1 2 a 3 . 9 6 a 4 . 2 0 a 0 . 8 9 a 04 a 08 a 06 a 82 a 30 a 3 . 7 5 a 3 . 9 2 a 0 . 9 1 a 3 . 3 1 a 3 . 9 7 a 4 . 1 7 a 3 . 4 1 a . 1 2 2 ) , 5 4 5 ) , 5 7 2 ) , 6 0 3 ) . 1 6 6 ) , 5 6 8 ) . 5 2 9 ) , 4 7 1 ) , 1 3 2 ) , 6 5 0 ) , 5 6 0 ) , 6 4 2 ) , 1 8 5 ) , 6 1 3 ) . 5 1 3 ) , 4 6 0 ) . 6 0 6 ) 0 , 2 , 3 , 3 , 0 , 1, . 9 6 a . 7 0 a . 1 2 b . 5 2 b . 8 7 a . 8 4 b 2 . 3 4 b 2 . 8 8 b 0 . 8 7 a 2 . 4 0 b 3 . 0 5 b 3 . 4 4 a 0 . 9 0 a 2 . 0 9 2 . 6 9 2 . 9 2 2 . 0 4 . 2 4 5 ) . 8 0 3 ) . 8 3 5 ) . 8 5 6 ) . 1 2 3 ) . 4 9 7 ) . 5 9 5 ) . 6 6 4 ) . 1 8 6 ) . 6 1 9 ) . 9 2 5 ) . 7 0 4 ) . 1 4 4 ) . 4 7 8 ) . 8 9 8 ) . 8 1 9 ) . 3 4 7 ) 1 . 2 7 1 . 8 9 2 . 1 1 2 . 6 0 1 . 0 6 0 5 31 47 1 . 1 5 15 33 39 1 . 1 9 1 .91 27 50 2 . 0 3 . 2 1 1 ) . 3 3 5 ) . 3 3 8 ) . 5 1 6 ) . 1 1 9 ) . 3 1 8 ) . 4 6 5 ) . 2 7 8 ) . 1 9 9 ) . 4 0 7 ) . 4 6 6 ) . 5 6 9 ) . 1 6 5 ) . 3 8 6 ) . 4 5 9 ) . 4 1 5 ) . 3 3 2 ) * V a l u e s i n p a r e n t h e s i s ± S D . - 8 2 -s t u d y b y D a n g e r f i e l d a n d B r i x ( 1 9 7 9 ) w h o f o u n d m e a n f o l i a r N c o n c e n t r a t i o n s i n a 2 4 y e a r o l d D o u g l a s - f i r s t a n d i n c r e a s e d t o 3 . 5 % i n t h e f i r s t y e a r a f t e r f e r t i l i z a t i o n w i t h 4 4 8 k g N / h a . S i m i l a r l y , E b e l l ( 1 9 7 2 ) a t t a i n e d m e a n f o l i a r N c o n c e n t r a t i o n s i n e x c e s s o f 3% a f t e r f e r t i l i z a t i o n w i t h 4 0 0 k g N / h a a n d o v e r 4% a f t e r f e r t i l i z a t i o n w i t h 8 0 0 k g N / h a . B r o c k l e y ( 1 9 8 1 ) n o t e d a s t r o n g m o i s t u r e x N i n t e r a c t i o n o n N u p t a k e i n D o u g l a s - f i r s e e d l i n g s a n d f o u n d m e a n f o l i a r N c o n c e n t r a t i o n s a t t h e h i g h e s t m o i s t u r e l e v e l r a n g e d f r o m 4 . 0 t o 5 . 2 % . A s i n t h e p r e s e n t s t u d y , t h e a b o v e f e r t i l i z e r e x p e r i m e n t s , w i t h t h e e x c e p t i o n o f B r o c k l e y , w h o a p p l i e d a m m o n i u m s u l p h a t e , u s e d a m m o n i u m n i t r a t e a s t h e N s o u r c e a s o p p o s e d t o t h e m o r e c o m m o n l y u s e d u r e a . A n i n c r e a s i n g n u m b e r o f s t u d i e s a r e s h o w i n g a s u p e r i o r i t y o f g r o w t h r e s p o n s e s f r o m a m m o n i u m n i t r a t e o v e r u r e a ( W e e t m a n a n d A l g a r , 1 9 7 4 ; N o m m i c k a n d M o l l e r , 1 9 8 1 ; D a n g e r f i e l d a n d B r i x , 1 9 7 9 ; M i l l e r a n d T a r r e n t , 1 9 8 3 ) . T h i s s u p e r i o r i t y h a s b e e n a t t r i b u t e d t o t h e g r e a t e r i n i t i a l u p t a k e o f N f r o m a m m o n i u m n i t r a t e t h a n f r o m u r e a ( D a n g e r f i e l d a n d B r i x , 1 9 7 9 ) . T h i s a p p e a r s t o b e t r u e e v e n i n t h o s e c a s e s w h e r e f o l i a r N c o n c e n t r a t i o n o n l y i n c r e a s e d t o 2 . 0 t o 2 . 5 % . I n t h e a b o v e - m e n t i o n e d s t u d y , ; D a n g e r f i e l d a n d B r i x ( 1 9 7 9 ) a d d e d a n e q u i v a l e n t a m o u n t o f u r e a a n d f o u n d m e a n f o l i a r N c o n c e n t r a t i o n s d i d n o t i n c r e a s e a b o v e 2 . 0 % . R e c e n t l y , M e l i n e t a l . ( 1 9 8 3 ) h a v e s h o w n a g r e a t e r u p t a k e o f NO3- t h a n NH4+ w h e n a m m o n i u m n i t r a t e i s u s e d a s a n N s o u r c e . M a n y s t u d i e s h a v e s h o w n t h a t N f r o m u r e a i s m o r e p r o n e t o l o s s e s b y v o l a t i l i z a t i o n o r - 8 3 -i m r a o b i l i z a t i o n i n t h e h u m u s l a y e r a n d s o i l m i c r o b i a l p o p u l a t i o n , a n d t h u s may n o t r e a c h t h e r o o t i n g z o n e ( O v e r r e i n , 1 9 6 9 ; N o m m i k a n d P o p o v i c , 1 9 7 1 ) . T h e n i t r a t e i o n h o w e v e r , i s h i g h l y m o b i l e a n d t h e r e f o r e m o r e r e a d i l y d i s t r i b u t e d t h r o u g h o u t t h e r o o t i n g z o n e ( D a n g e r f i e l d a n d B r i x , 1 9 7 9 ) . I n a d d i t i o n , s i n c e a m m o n i u m n i t r a t e d o e s n o t h a v e a p o s i t i v e i n f l u e n c e o n t h e pH l i k e u r e a d o e s , l o s s e s d u e t o v o l a t i l i z a t i o n o r m i c r o b i a l i m m o b i l i z a t i o n w i l l l i k e l y b e l e s s . I n c r e a s e d u p t a k e a n d s u p e r i o r i t y o f a m m o n i u m n i t r a t e o v e r u r e a h a s a l s o b e e n s h o w n t o o c c u r q u i t e r e a d i l y i n m a n y a g r i c u l t u r a l c r o p s ( M e n g e l a n d K i r k b y , 1 9 7 9 ) . I n t h e s e c a s e s h o w e v e r , s u p e r i o r i t y i s t h o u g h t t o b e r e l a t e d n o t o n l y t o i m p r o v e d u p t a k e , b u t a l s o t o d i f f e r e n c e s i n t h e c o m p l e x p h y s i o l o g i c a l a n d m e t a b o l i c p r o c e s s e s t h a t o c c u r i n t h e a s s i m i l a t i o n o f t h e t w o i o n s (NH4+ a n d NO3-) ( K i r k b y a n d H u g h e s , 1 9 7 0 ) . A t f i r s t g l a n c e , t h e l a r g e i n c r e a s e s i n N c o n c e n t r a t i o n a p p e a r t o b e l a r g e l y d u e t o l u x u r y c o n s u m p t i o n . H o w e v e r , e x a m i n a t i o n o f F i g u r e 1 3 r e v e a l s t w o d i s t i n c t c l u s t e r i n g o f p o i n t s . A s m e n t i o n e d b e f o r e , t h e a d d i t i o n o f N o r N p l u s K a l o n e r e s u l t e d i n a l a r g e i n c r e a s e i n n e e d l e N c o n c e n t r a t i o n , b u t o n l y a m o d e s t , a l t h o u g h s i g n i f i c a n t , I n c r e a s e i n n e e d l e w e i g h t . T h i s i s i n d i c a t i v e o f l u x u r y c o n s u m p t i o n ( F i g u r e 2 ) a n d s u g g e s t t h a t a l t h o u g h N a p p e a r s t o b e h i g h l y d e f i c i e n t , i t s a d d i t i o n w i l l r e s u l t i n o n l y a m o d e s t i n c r e a s e i n g r o w t h ( i t s h o u l d b e r e m e m b e r e d t h a t t h e h i g h N c o n c e n t r a t i o n s e x p e r i e n c e d may h a v e h a d a n e g a t i v e e f f e c t a n d t h a t l o w e r a p p l i c a t i o n r a t e s may h a v e r e s u l t e d i n 4 - 8 0 - , (g/IOOO needles) 80 120 160 2 0 0 240 N C O N T E N T (mg/IOOO needles) F I G U R E 1 3 . R e l a t i o n s h i p b e t w e e n f o l i a r N c o n c e n t r a t i o n , c o n t e n t a n d d r y w e i g h t . 320 - 8 5 -a l a r g e r n e e d l e w e i g h t r e s p o n s e ) . The a d d i t i o n o f P t o g e t h e r w i t h N o r N p l u s K h o w e v e r , r e s u l t e d i n a s i g n i f i c a n t l y g r e a t e r r e s p o n s e i n n e e d l e w e i g h t . T h i s i s c l e a r l y e v i d e n t i n F i g u r e 13 a s a s h i f t i n t h e c l u s t e r i n g " o f p o i n t s i n t o M a c y's ( 1 9 3 6 ) " p o v e r t y ' a d j u s t m e n t " r a n g e ( F i g u r e 2 ) . T h e s e f i n d i n g s s u g g e s t t h a t a l t h o u g h t h e t r e e s a r e d e f i c i e n t i n N, t h e i r a b i l i t y t o r e s p o n d t o N f e r t i l i z a t i o n i s l i m i t e d by a P d e f i c i e n c y . T h i s same p a t t e r n o f r e s p o n s e was e v i d e n t i n a l l f i v e s t a n d s o f t h i s s t u d y ( s e e A p p e n d i x I I ) . The a d d i t i o n o f P had a p o s i t i v e i n f l u e n c e on t h e N n u t r i t i o n o f t h e t r e e s and r e s u l t e d i n a s i g n i f i c a n t i n c r e a s e i n b o t h N c o n c e n t r a t i o n and c o n t e n t ( T a b l e 1 1 ) . I n a d d i t i o n , t h e r e was a h i g h l y s i g n i f i c a n t N x P i n t e r a c t i o n w h i c h a f f e c t e d N u p t a k e ( F i g u r e 1 4 ) . Numerous o t h e r s t u d i e s h a v e n o t e d i n c r e a s e d f o l i a r N c o n c e n t r a t i o n s f o l l o w i n g P f e r t i l i z a t i o n (Tamm, 1968, 1982; D i c k s o n and S a v i l l , 1974; F i e d l e r e t a l . , 1 9 8 3 ) . O t h e r s have n o t e d a s i g n i f i c a n t i n c r e a s e i n t h e r e l e a s e o f a v a i l a b l e N a f t e r t h e a d d i t i o n o f i n o r g a n i c P ( C a r e y e t a l . , 1 9 8 1 ) . Tamm ( 1 9 8 2 ) s u g g e s t s t h a t t h e i n c r e a s e i n N i s l a r g e l y due t o a s t i m u l a t i o n o f N m i n e r a l i z a t i o n . C a r e y e t a l . ( 1 9 8 1 ) h o w e v e r , n o t e d t h a t most s t u d i e s have f o u n d t h a t P f e r t i l i z a t i o n h a s e i t h e r had no e f f e c t o r a n e g a t i v e e f f e c t on N m i n e r a l i z a t i o n and s u g g e s t e d t h a t t h e e x a c t m e c h a n i s m i s n o t e n t i r e l y u n d e r s t o o d . I n t h e p r e s e n t s t u d y , P o n l y i n c r e a s d N u p t a k e when N was a l s o added ( F i g u r e 1 4 ) . The a d d i t i o n o f P a l o n e r e s u l t e d i n o n l y a s l i g h t and n o n - s i g n i f i c a n t i n c r e a s e i n f o l i a r N c o n t e n t and c o n c e n t r a t i o n . I n c r e a s i n g t h e amount o f P t o 100 and 150 -86-k g / h a h a d n o a p p a r e n t a d d i t i o n a l e f f e c t a n d r e s u l t e d i n a s l i g h t r e d u c t i o n i n N c o n t e n t . T h e s e f i n d i n g s c o n t r a s t e d w i t h D i c k s o n a n d S a v i l l (1974) w h o f o u n d t h a t t h e a d d i t i o n o f P a l o n e t o h i g h l y d e f i c i e n t N a n d P S i t k a s p r u c e p l a n t a t i o n s i n B r i t a i n r e s u l t e d i n a s i g n i f i c a n t i n c r e a s e i n b o t h f o l i a r N a n d P c o n c e n t r a t i o n s w h i c h i n t u r n l e d t o h i g h l y s i g n i f i c a n t g r o w t h r e s p o n s e s . F I G U R E 14. •50 kg P/ha c ^ 0 kg P/ha J 400 200 300 kg N/ha E f f e c t s o f N x P i n t e r a c t i o n o n N u p t a k e . P o i n t s f o l l o w e d b y t h e s a m e l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 . - 8 7 -N f e r t i l i z a t i o n a l s o h a d a s i g n i f i c a n t i n f l u e n c e o n t h e f o l i a r N c o n c e n t r a t i o n s o f b o t h h e m l o c k a n d c e d a r ( T a b l e 1 A ) . H o w e v e r , t h e e f f e c t s t e n d e d t o b e l e s s t h a n i n s p r u c e . M o r e o v e r , i n c r e a s e s i n t h e N c o n c e n t r a t i o n s o f c e d a r f o l i a g e t e n d e d t o b e l e s s t h a n t h a t o f h e m l o c k ( T a b l e 1 A ) . M e a n f o l i a r N c o n c e n t r a t i o n s o f h e m l o c k f r o m t h e c o n t r o l p l o t s w a s 0 . 9 6 % i n d i c a t i n g t h a t a s e v e r e d e f i c i e n c y may a l s o e x i s t i n t h i s s p e c i e s ( T a b l e 1 ) . I n c o n t r a s t , f o l i a r N l e v e l s o f w e l l g r o w i n g h e m l o c k f r o m t h e H A - p h a s e w e r e c o n s i d e r a b l y h i g h e r ( 1 . 5 2 % ) . M e a n f o l i a r N l e v e l s o f u n f e r t i l i z e d h e m l o c k w e r e n o t s i g n i f i c a n t l y d i f f e r e n t f r o m t h a t o f s p r u c e . H o w e v e r c e d a r , w i t h a m e a n c o n c e n t r a t i o n o f 1 . 2 7 % , w a s s i g n i f i c a n t l y g r e a t e r ( p = . 0 1 ) t h a n b o t h h e m l o c k a n d s p r u c e . T h i s f i n d i n g w a s c o n s i s t e n t w i t h t h e p r e l i m i n a r y r e s u l t s o f L e w i s ( 1 9 8 2 ) w h o a l s o n o t e d t h a t t h e f o l i a r n i t r o g e n c o n c e n t r a t i o n o f c e d a r i n t h e C H - p h a s e w a s c o n s i d e r a b l y h i g h e r t h a n e i t h e r s p r u c e o r h e m l o c k . No e x p l a n a t i o n c a n b e o f f e r e d f o r t h e h i g h e r N c o n c e n t r a t i o n s f o u n d i n t h e c e d a r . H o w e v e r , i t s u g g e s t s t h a t f a c t o r s o t h e r t h a n t h e l a c k o f a v a i l a b l e N w e r e c a u s i n g t h e s e v e r e N d e f i c i e n c i e s i n t h e s p r u c e a n d h e m l o c k . M o r e o v e r , t h e s e f i n d i n g s w e r e c o n s i s t e n t w i t h t h e i m p r o v e d r e l a t i v e g r o w t h o f c e d a r a n d a l s o w i t h t h a t o f t h e N m i n e r a l i z a t i o n s t u d y w h i c h i n d i c a t e d , t h a t a l t h o u g h N m i n e r a l i z a t i o n w a s s i g n i f i c a n t l y l e s s i n t h e C H - p h a s e t h a n i n t h e H A - p h a s e , t h e a m o u n t s b e i n g r e l e a s e d a p p e a r e d t o b e r e l a t i v e l y h i g h . D e s p i t e t h e h i g h e r N c o n c e n t r a t i o n s i n t h e c e d a r h o w e v e r , t h e y w e r e s t i l l l o w a n d p o s s i b l y d e f i c i e n t - 8 8 -( T a b l e 1 ) . T h i s s u g g e s t s t h a t e v e n t h e g r o w t h o f c e d a r may b e s i g n i f i c a n t l y i m p r o v e d b y N f e r t i l i z a t i o n . E f f e c t s o n F o l i a r P h o s p h o r u s P h o s p h o r u s f e r t i l i z a t i o n n o t o n l y i n c r e a s e d f o l i a r P c o n c e n t r a t i o n a n d c o n t e n t , b u t a l s o h a d a s i g n i f i c a n t i n f l u e n c e o n n e e d l e w e i g h t , l e a d e r g r o w t h , f o l i a r N c o n c e n t r a t i o n a n d f o l i a r N , K , C a a n d Mg c o n t e n t ( T a b l e 1 1 ) . S i m i l a r i n c r e a s e s i n f o l i a r n u t r i e n t c o m p o s i t i o n h a v e b e e n n o t e d f o l l o w i n g P f e r t i l i z a t i o n i n o t h e r s p e c i e s s u c h a s P i c e a a b i e s ( F i e d l e r e t a l . , 1 9 8 3 ) . I n a d d i t i o n , t h e r e w a s a h i g h l y s i g n i f i c a n t N x P i n t e r a c t i o n a n d a s i g n i f i c a n t N x K i n t e r a c t i o n w h i c h a f f e c t e d t h e P c o n c e n t r a t i o n b u t n o t c o n t e n t . F i g u r e 1 5 i l l u s t r a t e s t h e e f f e c t o f t h e N x P i n t e r a c t i o n . F o l i a r P c o n c e n t r a t i o n s d e c r e a s e d w i t h i n c r e a s i n g r a t e s o f N w h e n N a n d P w e r e a d d e d t o g e t h e r , b u t i n c r e a s e d w h e n N w a s a d d e d a l o n e ( F i g u r e 1 5 ) . T h e d e c r e a s e i n c o n c e n t r a t i o n f r o m N p l u s P f e r t i l i z a t i o n i s d u e t o a d i l u t i o n e f f e c t f r o m t h e e n h a n c e d g r o w t h . N o t e t h a t d e s p i t e t h e d e c r e a s e i n c o n c e n t r a t i o n , f o l i a r P c o n t e n t w a s s i g n i f i c a n t l y i n c r e a s e d ( T a b l e 1 1 ) . T h e s e f i n d i n g s a r e c o n s i s t e n t w i t h o t h e r s t u d i e s . S h e p p a r d a n d R a c z ( 1 9 8 0 ) c i t e d n u m e r o u s e x a m p l e s w h e r e a p o s i t i v e a m m o n i u m i o n e f f e c t w a s n o t e d o n t h e u p t a k e o f P . T h e y s u g g e s t e d t h a t t h e m a i n m e c h a n i s m s r e s p o n s i b l e f o r t h i s e f f e c t w a s i n c r e a s e d r o o t g r o w t h , i n c r e a s e d a b i l i t y t o a b s o r b a n d t r a n s l o c a t e P , a n d a pH e f f e c t a t t h e s o i l - r o o t i n t e r f a c e i n c r e a s i n g P s o l u b i l i t y . -89-FIGURE 15. 02Ld 0-19-..o O 017 < F 015 LU O O 013 O Oil :50KgP/ha 0 Kg P/ha 200 -Kg N/ha 300 400 E f f e c t o f N x P i n t e r a c t i o n on P c o n c e n t r a t i o n . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p=.05. Mean f o l i a r P c o n c e n t r a t i o n s o f t h e S i t k a s p r u c e i n t h e c o n t r o l p l o t s was 0.11% ( T a b l e 1 5 ) . As w i t h N, t h i s was a g a i n w e l l b e l o w t h e c r i t i c a l v a l u e o f 0.14% ( T a b l e 1 ) . Even i n t h e HA-phase where g r o w t h was v e r y good, P c o n c e n t r a t i o n s were s t i l l l o w , a v e r a g i n g o n l y 0.13%. T h i s e s t i m a t e h o w e v e r , was c o n s i d e r a b l y l o w e r t h a n t h a t o f 0.16% o b t a i n e d by L e w i s ( 1 9 8 2 ) f r o m S i t k a s p r u c e on s i m i l a r s i t e s and i n d i c a t e d t h a t a f a i r amount o f v a r i a b i l i t y e x i s t s between p l a n t a t i o n s . - 9 0 -N o n e - t h e - l e s s , a l l t h e t r e e s f r o m t h e H A - p h a s e s a m p l e d i n t h e p r e s e n t s t u d y e x h i b i t e d e x c e l l e n t g r o w t h , w i t h h e i g h t i n c r e m e n t s r a n g i n g f r o m A 7 t o 8 5 c m . T h i s w o u l d s e e m t o V i n d i c a t e t h a t s u b s t a n t i a l g a i n s i n g r o w t h o f S i t k a s p r u c e o n t h e C H - p h a s e may b e a c h i e v e d t h r o u g h a m o d e s t i n c r e a s e i n f o l i a r P c o n c e n t r a t i o n s p r o v i d e d t h e N n u t r i t i o n w e r e i m p r o v e d . U n f o r t u n a t e l y , t h i s d i d n o t o c c u r i n t h e p r e s e n t s t u d y . A l t h o u g h t h e a d d i t i o n o f N o r N p l u s K a l o n e d i d r e s u l t i n a s l i g h t i n c r e a s e i n f o l i a r P t o a b o u t 0 . 1 2 % , t h e r e w a s o n l y a m i n i m a l e f f e c t o n g r o w t h c o m p a r e d t o t h e N p l u s P t r e a t m e n t s ( F i g u r e 1 0 a n d 1 1 ) . T h e l a c k o f r e s p o n s e i n t h e s e c a s e s h o w e v e r , may b e d u e t o t h e h i g h f o l i a r N c o n c e n t r a t i o n s d i s c u s s e d p r e v i o u s l y w h i c h w o u l d p r o b a b l y c o m p o u n d t h e e f f e c t s o f t h e l o w P c o n c e n t r a t i o n s . V a n d e n D r i e s s c h e ( 1 9 7 A ) n o t e d t h a t t h e o p t i m u m N / P r a t i o f o r m a n y s p e c i e s i s b e w e e n 6 t o 1 6 a n d L e y t o n ( 1 9 5 8 ) s u g g e s t e d a v a l u e o f 1 0 f o r S i t k a s p r u c e . N / P r a t i o s i n t h e p r e s e n t s t u d y r a n g e d b e t w e e n 2 8 a n d 3 5 f o r N a n d N p l u s K t r e a t m e n t s a s c o m p a r e d t o a r a n g e o f 1 7 t o 2 3 f o r t h e N p l u s P t r e a t m e n t s a n d a m e a n o f 1 0 f o r t h e s p r u c e f r o m t h e H A - p h a s e . D e s p i t e t h e a p p a r e n t l a c k o f P o n t h e s e s i t e s , t h e a d d i t i o n o f P o r P p l u s K a l o n e h a d n o e f f e c t o n g r o w t h o r n e e d l e w e i g h t , a l t h o u g h f o l i a r c o n c e n t r a t i o n s w e r e s i g n i f i c a n t l y i n c r e a s e d ( T a b l e 1 5 ) . H o w e v e r , t h e a d d i t i o n o f P a n d , N t o g e t h e r r e s u l t e d i n a l a r g e i n c r e a s e i n n e e d l e w e i g h t a n d i s c l e a r l y e v i d e n t i n F i g u r e 1 6 a s a 1 1 C " s h i f t ( F i g u r e 2 ) , s u g g e s t i n g t h a t b o t h N a n d P a r e d e f i c i e n t . T h e f a c t t h a t N a l o n e r e s u l t e d i n s o m e i n c r e a s e i n g r o w t h , - 9 1 -w h e r e a s P a l o n e d i d n o t , s u g g e s t e d t h a t N w a s m o r e l i m i t i n g . H o w e v e r , g i v e n t h e l a r g e a d d i t i o n a l g a i n s d e r i v e d f r o m a p p l y i n g b o t h N a n d P t o g e t h e r , i t s e e m s l i k e l y t h a t f o r a n y r e m e d i a l f e r t i l i z a t i o n p r o g r a m t o b e e f f e c t i v e , b o t h N a n d P w i l l h a v e t o b e a p p l i e d . M o r e o v e r , i f a n y o t h e r t r e a t m e n t , s u c h a s s c a r i f i c a t i o n , i s u n d e r t a k e n o n t h e s e s i t e s t o i m p r o v e t h e N s t a t u s , a t o p d r e s s i n g o f P may s t i l l b e r e q u i r e d i f m a x i m u m b e n e f i t s a r e t o b e a c h i e v e d . A s i n s p r u c e , P f e r t i l i z a t i o n t e n d e d t o r e s u l t i n a h i g h l y s i g n i f i c a n t i n c r e a s e i n f o l i a r P c o n c e n t r a t i o n s i n b o t h c e d a r a n d h e m l o c k ( T a b l e 1 5 ) . A f t e r f e r t i l i z a t i o n , f o l i a r P l e v e l s t e n d e d t o b e h i g h e s t i n h e m l o c k a n d l o w e s t i n s p r u c e . U n l i k e s p r u c e h o w e v e r , N f e r t i l i z a t i o n t e n d e d t o r e s u l t i n a r e d u c t i o n i n f o l i a r P c o n c e n t r a t i o n s , a n d w a s p a r t i c u l a r l y n o t i c e a b l e w i t h c e d a r . M o r e o v e r , i n c r e a s i n g r a t e s o f N t e n d e d t o r e s u l t i n a c o r r e s p o n d i n g d e c l i n e o f f o l i a r P w h e t h e r P w a s a d d e d o r n o t ( T a b l e 1 5 ) . M e a n f o l i a r P c o n c e n t r a t i o n s o f h e m l o c k i n t h e c o n t r o l p l o t s w a s 0 . 1 3 % . W h i l e t h i s v a l u e i s c o n s i d e r e d t o b e - s e v e r e l y d e f i c i e n t ( T a b l e 1 ) , i t w a s n o t o n l y s i g n i f i c a n t l y g r e a t e r t h a n t h e c o n c e n t r a t i o n f o u n d i n s p r u c e ( T a b l e 1 5 ) , b u t , i t w a s a l s o s l i g h t l y h i g h e r t h a n t h e e s t i m a t e o f 0 . 1 2 % o b t a i n e d f o r w e l l g r o w i n g h e m l o c k f r o m t h e H A - p h a s e . T h e e s t i m a t e s o b t a i n e d i n t h i s s t u d y w e r e n o t c o n s i s t e n t w i t h t h o s e o f L e w i s ( 1 9 8 2 ) w h o f o u n d m e a n f o l i a r P c o n c e n t r a t i o n t o b e 0 . 1 6 % a n d 0 . 2 5 % f o r h e m l o c k g r o w i n g o n t h e C H - a n d H A - p h a s e s , r e s p e c t i v e l y . B a k e r ( 1 9 7 0 ) h o w e v e r , f o u n d f o l i a r P c o n c e n t r a t i o n s i n s i m i l a r h i g h s i t e h e m l o c k T A B L E 15 , W i t h i n a n d b e t w e e n s p e c i e s c o m p a r i s o n s o f mean f o l i a r P concentrfltinn. tt s p r u c e , h e m l o c k a n d c e d a r . T r e a t m e n t s c o n n e c t e d by [ h e « ! " 0 ? 0 , r ^ r | K W e l 8 h ° f ° F a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p . . 0 1 . f o l l o w e d by t h e same l e t t e r W I T H I N S P E C I E S COMPARISON S P R U C E HEMLOCK CEDAR • B E T W E E N S P E C I E S COMPARISON S P R U C E HEMLOCK NO NOK N l N2K NIK N3K N3 N2 NPKT N3P N3PK N I P N2PK N2P N1PK NOP NOPK -TREATMENT-S' 2K NIK N l N3K N3 N2 NOK NO NPKT N3PK N2PK N2P N3P N1PK N I P NOPK NOP N3K N2K N I K N2 N3 NOK N l NO NOP NOPK N3PK N3P N2PK N1PK N2P NPKT N I P TREATMENT NO N l N2 N3 NOP N I P N2P N3P NOK NIK N2K N3K NOPK N1PK N2PK N3PK NPKT CEDAR 0 . 1 1 a 0 . 1 1 a 0 . 1 2 a 0 . 1 2 a 0 . 2 0 a 18 a 19 a 18 11 12 ,11 12 0 . 0 . 0 . 0 . 0 . 0 . 0 . 0 . 0 . 0 . 0 . 22 a 19 a 19 a 18 a 0 . 1 8 a . 0 2 1 ) . 0 2 2 ) . 0 2 3 ) . 0 2 4 ) . 0 4 0 ) . 0 2 1 ) . 0 2 5 ) . 0 2 2 ) . 0 2 2 ) . 0 2 4 ) . 0 2 3 ) . 0 2 2 ) . 0 4 0 ) . 0 2 3 ) . 0 2 2 ) . 0 1 8 ) . 0 1 7 ) 13 b 10 a 11 a 10 a 44 b 28 27 27 12 09 08 11 0 . 3 8 0 . 2 8 0 . 2 6 0 . 2 3 0 . 2 2 . 0 3 2 ) . 0 3 5 ) . 0 2 9 ) . 0 2 4 ) . 0 7 0 ) . 0 6 7 ) . 0 9 2 ) . 0 5 0 ) . 0 4 0 ) . 0 2 8 ) . 0 1 0 ) . 0 4 1 ) . 0 9 5 ) . 0 9 4 ) . 0 8 0 ) . 0 6 4 ) . 0 4 4 ) 0 . 1 8 0 . 1 8 0 . 1 7 0 . 0 . 0 . 0 . 0 , 0 . 0 . 0 . 17 19 28 ,25 ,24 17 17 16 0 . 1 6 0 0 0 . 2 4 b 0 . 2 3 a 0 . 2 6 b ,22 a ,24 b . 0 3 1 ) . 0 3 5 ) . 0 2 4 ) . 0 4 2 ) . 0 3 0 ) . 0 6 0 ) . 0 3 7 ) . 0 5 1 ) . 0 2 8 ) . 0 2 6 ) . 0 3 3 ) . 0 2 6 ) . 0 3 1 ) . 0 5 9 ) . 0 5 3 ) . 0 5 5 ) . 0 4 5 ) V a l u e s i n p a r e n t h e s i s + S D . I o ro I P CONCENTRATION (%) CO PO 3 fD O- I-1 O. at TJ GO •1 >< 1 on O we on O H* H- ~z. 00 —1 _ — ht c r m O • etwe NT fD 3 Fo H> O \ li O Co O i o r3 o fD o fD nc CL fD fD nt "i CO rt H-O 3 ** CD O o 3 rt fD 3 rt ro ^ c o o i x ^ C j j r \ j ^ a f X ) C o - U O T C ^ ^ C j o r ^ T ) L o r M t - ' O W ( N j ^ o c j r O i - ' Q u r O ' - - o 1 Z^ s m CD m o -C6-- 9 4 -s t a n d s t o r a n g e f r o m 0 . 1 4 % t o 0 . 2 1 % . B e c a u s e t h i s s t u d y w a s n o t d e s i g n e d t o s t u d y h e m l o c k a n d t h e s a m p l e s i z e w a s r e l a t i v e l y s m a l l ( 2 3 c o n t r o l t r e e s f r o m t h e C H - p h a s e a n d 1 0 t r e e s f r o m t h e H A - p h a s e ) t h e s e e s t i m a t e s s h o u l d b e v i e w e d w i t h c a u t i o n . T h e s o m e w h a t b e t t e r g r o w t h o f h e m l o c k a s c o m p a r e d t o s p r u c e a f t e r N o r N p l u s K f e r t i l i z a t i o n s u g g e s t e d a b e t t e r P s t a t u s i n h e m l o c k . H o w e v e r , g i v e n t h e h i g h l y s i g n i f i c a n t s y n e r g i s t i c e f f e c t o f P w h e n a d d e d w i t h N o n h e m l o c k g r o w t h , i t a p p e a r e d t h a t P w a s d e f i c i e n t . M e a n f o l i a r P c o n c e n t r a t i o n s o f c e d a r i n t h e c o n t r o l p l o t s i s 0 . 1 8 % , w h i c h w a s e x t r e m e l y h i g h c o m p a r e d t o t h a t o f s p r u c e o r h e m l o c k ( T a b l e 1 5 ) . B e c a u s e o f t h e l a c k o f i n f o r m a t i o n o n c e d a r h o w e v e r , i t i s d i f f i c u l t t o s a y h o w t h i s v a l u e c o m p a r e s w i t h t h e g e n e r a l n u t r i t i o n a l r e q u i r e m e n t s o f t h e s p e c i e s . H o w e v e r , g i v e n t h e r e l a t i v e l y g o o d g r o w t h e x p e r i e n c e d o n t h e s e s i t e s , i t w o u l d a p p e a r t h a t t h e P s t a t u s w a s a d e q u a t e o r , a t m o s t , o n l y m a r g i n a l l y d e f i c i e n t . G r a h a m ( 1 9 8 2 ) n o t e d t h a t c e d a r o f t e n r e s p o n d e d f a v o u r a b l y t o r e l e a s e e v e n t h o u g h f o l i a r P a n d N c o n c e n t r a t i o n s w e r e o n l y 0 . 1 3 % a n d 0 . 9 0 % t o 0 . 9 5 % , r e s p e c t i v e l y , w h i c h s u g g e s t e d t h a t t h e s p e c i e s i s c a p a b l e o f e x h i b i t i n g g o o d g r o w t h o n l o w P l e v e l s . Why c a n c e d a r p e r f o r m b e t t e r o n t h e s e s i t e s t h a n e i t h e r s p r u c e o r h e m l o c k ? I t i s o b v i o u s t h a t t h e s p e c i e s i s m o r e e f f i c i e n t i n e x t r a c t i n g o r c o m p e t i n g f o r a v a i l a b l e n u t r i e n t s t h a n e i t h e r o f i t s c o u n t e r p a r t s . I t i s c o n c e i v a b l e t h a t t h i s may b e r e l a t e d t o d i f f e r e n c e s i n m y c o r r h i z a l a s s o c i a t i o n s b e t w e e n t h e s p e c i e s . N u m e r o u s s t u d i e s h a v e s h o w n t h a t p l a n t s i n f e c t e d w i t h m y c o r r h i z a e e x h i b i t b e t t e r - 9 5 -g r o w t h t h a n n o n - i n f e c t e d p l a n t s . I n v a r i a b l y , t h i s i m p r o v e d g r o w t h h a s b e e n a t t r i b u t e d t o a n i m p r o v e m e n t i n t h e p l a n t s ' n u t r i t i o n , a n d i n p a r t i c u l a r P , b u t a l s o t o s o m e e x t e n t N . ( T i n k e r , 1 9 7 9 ; R o v i r a e t a l . , 1 9 8 3 ) . T h e m y c o r r h i z a l f u n g i a s s o c i a t e d w i t h c e d a r a r e d i f f e r e n t f r o m t h o s e o f s p r u c e a n d h e m l o c k . C e d a r f o r m s a s s o c i a t i o n s w i t h v e s i c u l a r - a r b u s c u l a r ( V A ) f u n g i , w h e r e a s , b o t h s p r u c e a n d h e m l o c k f o r m a s s o c i a t i o n s w i t h e c t o m y c o r r h i z a l f u n g i ( P a r k e e t a l . , 1 9 8 3 ) . I t i s p o s s i b l e t h a t t h e V A - m y c o r r h i z a e o f c e d a r a r e m o r e t o l e r a n t o f t h e c o n d i t i o n s f o u n d o n t h e s e s i t e s . P a r k e e t a l . ( 1 9 8 3 ) n o t e d t h a t t h e d o m i n a n t s p e c i e s i n f e c t i n g c e d a r w a s G l o m u s t e n u e , a s p e c i e s w h i c h i s k n o w n t o t o l e r a t e l o w P l e v e l s . M o r e o v e r , t h e r e may b e s o m e r e l a t i o n s h i p b e t w e e n t h e a b i l i t y o f t h e m y c o r r h i z a e t o t h r i v e o n t h e s e s i t e s a n d t h e " s a l a l e f f e c t " d i s c u s s e d p r e v i o u s l y , a l t h o u g h i t s h o u l d b e n o t e d t h a t c e d a r , l i k e s p r u c e a n d h e m l o c k , i s c o n s i d e r e d t o b e " h e a t h e r s e n s i t i v e " ( E v e r a r d , 1 9 7 4 ) . I n a n y e v e n t , f u r t h e r d i s c u s s i o n o f s u c h p o s s i b i l i t i e s a r e b e y o n d t h e s c o p e o f t h i s t h e s i s , a n d c a n o n l y b e s p e c u l a t e d u p o n u n t i l f u r t h e r i n v e s t i g a t i o n s a r e u n d e r t a k e n . E f f e c t s o n F o l i a r P o t a s s i u m A l t h o u g h K f e r t i l i z a t i o n r e s u l t e d i n a h i g h l y s i g n i f i c a n t i n c r e a s e i n b o t h f o l i a r K c o n c e n t r a t i o n a n d c o n t e n t , a s t r o n g a n t a g o n i s t i c e f f e c t o f N o n K r e s u l t e d i n a d r a m a t i c d e c r e a s e i n t h e f o l i a r K l e v e l s b e l o w t h a t o f t h e c o n t r o l s . I n a d d i t i o n , t h e r e w e r e a n u m b e r o f h i g h l y s i g n i f i c a n t N x P a n d N x K i n t e r a c t i o n s w h i c h i n f l u e n c e d - 9 6 -b o t h K c o n c e n t r a t i o n a n d c o n t e n t ( F i g u r e s 17 a n d 1 8 ) . T h e a d d i t i o n o f P a l o n e r e s u l t e d i n a s i g n i f i c a n t i n c r e a s e i n f o l i a r K c o n c e n t r a t i o n a n d c o n t e n t , h o w e v e r , w h e n a d d e d t o g e t h e r w i t h N , K c o n t e n t i n c r e a s e d ( F i g u r e 1 8 ) , w h e r e a s , c o n c e n t r a t i o n d e c r e a s e d ( F i g u r e 1 7 ) . T h e r e d u c t i o n i n c o n c e n t r a t i o n w a s d u e t o a g r o w t h d i l u t i o n p h e n o m e n o n r a t h e r t h a n a n t a g o n i s m b e t w e e n t h e P a n d K i o n s ( F i g u r e 1 9 ) . On t h e o t h e r h a n d , N f e r t i l i z a t i o n r e s u l t e d i n a h i g h l y s i g n i f i c a n t a n d d r a m a t i c r e d u c t i o n i n b o t h f o l i a r K c o n c e n t r a t i o n a n d c o n t e n t ( F i g u r e s 17 a n d 1 8 ) . T h i s e f f e c t w a s e v i d e n t w h e t h e r o r n o t K w a s a d d e d . H o w e v e r , o n t h o s e p l o t s w h e r e K w a s a d d e d , f o l i a r K l e v e l s t e n d e d t o b e h i g h e r ( T a b l e 1 6 ) e x c e p t a t t h e h i g h e s t N r a t e s w h e r e t h i s t r e n d w a s r e v e r s e d ( F i g u r e s 1 7 a n d 1 8 ) . M e a n f o l i a r K l e v e l s o f t r e e s i n t h e c o n t r o l p l o t s w a s 0 . 5 7 % a s c o m p a r e d t o 0 . 5 2 % f o r w e l l g r o w i n g s p r u c e o f t h e H A - p h a s e . T h e s e v a l u e s s u g g e s t t h e p o s s i b i l i t y o f a m o d e r a t e K d e f i c i e n c y ( T a b l e 1 ) . T h e a d d i t i o n o f K o r P p l u s K a l o n e h a d n o e f f e c t o n n e e d l e w e i g h t , b u t d i d r e s u l t i n a v e r y l a r g e i n c r e a s e i n f o l i a r K c o n c e n t r a t i o n ( F i g u r e 1 9 ) . H o w e v e r , w h e n N w a s i n c l u d e d , f o l i a r K l e v e l s d r o p p e d t o 0 . 4 1 % , 0 . 3 5 % a n d 0 . 3 4 % f o r t h e 2 0 0 , 3 0 0 a n d 4 0 0 k g N / h a a p p l i c a t i o n r a t e s , r e s p e c t i v e l y . A l t h o u g h s o m e o f t h e d e c r e a s e i n K c o n c e n t r a t i o n c a n b e a t t r i b u t e d t o a d i l u t i o n e f f e c t , i t a p p e a r e d t o b e l a r g e l y d u e t o a n a n t a g o n i s t i c i n f l u e n c e o f t h e h i g h N c o n c e n t r a t i o n s . T h i s w a s e v i d e n t f r o m t h e s t r o n g " E " s h i f t s i n F i g u r e 1 9 p l u s t h e h i g h l y s i g n i f i c a n t n e g a t i v e c o r r e l a t i o n b e t w e e n N a n d K ( r = - 0 . 7 2 3 5 ; -97-•76,-NXP INTERACTION \ NxK INTERACTION O o 200 kg N/ha fi- ao kg P/ha'36 50 kg P/ha 1 I 300 400 O L r -< f— LU O 0 kg K/ha 50 kg K/ha 200 300 400 kg N/ha FIGURE 1 7 . E f f e c t s o f N x P and N x K i n t e r a c t i o n s on p o t a s s i u m c o n c e n t r a t i o n . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 5 . -98-kg N/ha FIGURE 18. E f f e c t s o f N x P and N x K i n t e r a c t i o n s on p o t a s s i u m c o n t e n t . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p=.05. I-4CU I-2.0J O 1-00-4 r -< or Z 0-80 LJ o 0-60J 0-40 J 0-20 (g/1000 needles) T 1 r 16 20 24 28 32 36 K CONTENT (mg/1000 needles) LEGEND • NO 2 N l 3 N2 A N3 5 NOP 6 N IP 7 N2P 8 N3P 9 NOK 10 NIK ] 1 N2K 12 N3K 13 NOPK 14 N1PK 15 N2PK 16 N3PK 17 NPKT 40 44 F I G U R E 1 9 . R e l a t i o n s h i p b e t w e e n f o l i a r K c o n c e n t r a t i o n , c o n t e n t a n d d r y w e i g h t . - 1 0 0 -n o t e : e x c l u d e s t r e a t m e n t s NOK a n d N O P K ) . T h e s e p a t t e r n s w e r e c o n s i s t e n t i n a l l f i v e p l a n t a t i o n s s e l e c t e d f o r s t u d y ( s e e A p p e n d i x I I ) . T h e r e a r e n u m e r o u s e x a m p l e s , p a r t i c u l a r l y i n a g r i c u l t u r e , o f a n t a g o n i s t i c e f f e c t s o f N o n K , h o w e v e r , t h e s u p p r e s s i o n o f K i n t h e s e c a s e s w a s r e l a t e d t o a m m o n i u m i o n s r a t h e r t h a n n i t r a t e i o n s ( M u r p h y , 1 9 8 0 ) . I n c o n t r a s t w i t h t h e p r e s e n t s t u d y , t h e a d d i t i o n o f a n i t r a t e s o u r c e o f N , s u c h a s a m m o n i u m n i t r a t e , o r s i m p l y t h e a d d i t i o n o f K w a s s u f f i c i e n t t o o v e r c o m e t h e a n t a g o n i s t i c e f f e c t o f t h e a m m o n i u m i o n ( M u r p h y , 1 9 8 0 ) . Two m a i n t h e o r i e s w e r e s u g g e s t e d t o e x p l a i n t h i s e f f e c t . W o o d h o u s e a n d H a r d w i c k ( 1 9 6 6 ) s u g g e s t e d t h a t s i n c e NH4.+ a n d K+ a r e s i m i l a r i n s i z e a n d c h a r g e , t h a t NH4+ c o u l d c o m p e t e w i t h K+ i o n s f o r r o o t s u r f a c e a b s o r p t i o n s i t e s s p e c i f i c f o r u n i v a l e n t c a t i o n s . D e k o c k ( 1 9 7 0 ) h o w e v e r , n o t e d t h a t i n s o m e p l a n t s , C a , a d i v a l e n t c a t i o n , may a l s o b e i n h i b i t e d ; t h e r e f o r e r o o t s u r f a c e c o m p e t i t i o n i s n o t t h e o n l y f a c t o r i n v o l v e d . B a r k e r e t a l . ( 1 9 6 7 ) p r o p o s e d t h a t h i g h c o n c e n t r a t i o n s o f a m m o n i u m c o u l d n o t o n l y d i s p l a c e e x c h a n g e a b l e K f r o m t h e s o i l c o l l o i d s , b u t a l s o p r e v e n t n o n - e x c h a n g e a b l e K f r o m b e c o m i n g a v a i l a b l e . A p p a r e n t l y , a s i g n i f i c a n t a m o u n t o f t h e n o n - e x c h a n g e a b l e f o r m s o f K c a n be m a d e a v a i l a b l e t o t r e e s , p a r t i c u l a r l y i n K d e f i c i e n t s o i l s ( W e l c h a n d S c o t t , 1 9 6 1 ; M e n g e l a n d K i r k b y , 1 9 7 9 ) . B e c a u s e o f t h i c k o r g a n i c a c c u m u l a t i o n s o n t h e C H - p h a s e i t i s d o u b t f u l t h a t n o n - e x c h a n g e a b l e f o r m s o f K p l a y a s i g n i f i c a n t r o l e i n t h e K n u t r i t i o n o f t h e s p r u c e . O r g a n i c s o i l s a r e o f t e n l o w i n K ( M e n g e l a n d K i r k b y , 1 9 7 9 ) . - 1 0 1 -S h i c k l u n a e t a l . ( 1 9 7 2 ) n o t e d t h a t a l t h o u g h o r g a n i c s o i l s h a v e h i g h C E C s , h u m u s c o l l o i d s h a v e v e r y l o w f i x i n g p o w e r s a n d t h u s m o s t K r e m a i n s i n r e a d i l y a v a i l a b l e f o r m s w h i c h c a n b e e a s i l y l e a c h e d . L e a c h i n g l o s s e s o f K may b e g r e a t e r d u e t o t h e a p p l i c a t i o n o f a m m o n i u m n i t r a t e a s o p p o s e d t o u r e a s i n c e t h e n i t r a t e i o n c o u l d a c t a s a c a r r i e r i o n f o r d i s p l a c e d K+ i o n s p r e v e n t i n g r e a b s o r p t i o n o n t o t h e s o i l c o l l o i d s . V i m m e r s t e d t a n d O s m o n d ( 1 9 6 3 ) a t t r i b u t e d a r e d u c t i o n i n e x c h a n g e a b l e K a f t e r t h e a p p l i c a t i o n o f a m m o n i u m n i t r a t e t o c o m p e t i t i o n b e t w e e n K+ a n d NH4+ i o n s f o r e x c h a n g e s i t e s . S i m i l a r l y , C o l e a n d G e s s e l ( 1 9 6 8 ) n o t e d s i g n i f i c a n t l o s s e s o f K f r o m t h e f o r e s t f l o o r a f t e r t h e a d d i t i o n o f u r e a a n d a m m o n i u m s u l p h a t e a n d t h a t l o s s e s w e r e g r e a t e r w h e n a m m o n i u m s u l p h a t e w a s u s e d . P r e s u m a b l y i n t h i s c a s e , i t i s t h e s u l p h a t e i o n t h a t a c t s a s a c a r r i e r i o n f o r d i s p l a c e d K+ i o n s . L o s s o f K b y l e a c h i n g may b e p a r t i c u l a r l y d e t r i m e n t a l o n t h e s e s i t e s , s i n c e p r i o r t o f e r t i l i z a t i o n , t h e o c c a s i o n a l t r e e w a s e x h i b i t i n g v i s u a l s y m p t o m s c h a r a c t e r i s t i c o f K d e f i c i e n c y . I n c o n i f e r s , s u c h s y m p t o m s f i r s t a p p e a r a s a g e n e r a l c h l o r o s i s , f o l l o w e d b y a f o l i a g e d i s c o l o u r a t i o n o f a p u r p l i s h - t i n g e o r b r o n z i n g , o f t e n r e f e r r e d t o a s " s c o r c h i n g " , o f t h e m o s t r e c e n t l y m a t u r e d , c u r r e n t y e a r s f o l i a g e ( F i g u r e 2 0 a ) ( B e n z i a n , 1 9 6 5 ; L e a f , 1 9 6 7 ) . D u r i n g t h e c o l l e c t i o n o f f o l i a g e i n t h e f a l l , t h e n u m b e r o f t r e e s e x h i b i t i n g t h e s e s y m p t o m s h a d i n c r e a s e d d r a m a t i c a l l y ( F i g u r e 2 0 b ) . A l l t r e e s e x h i b i t i n g K d e f i c i e n c y s y m p t o m s o c c u r r e d o n p l o t s r e c e i v i n g 3 0 0 a n d 4 0 0 k g N / h a . H o w e v e r , a l t h o u g h m a n y -102-FIGURE 2 0 a . S i t k a s p r u c e p r i o r t o f e r t i l i z a t i o n e x h i b i t i n g b r o n z i n g o r s c o r c h i n g o f f o l i a g e . N o t e t h e r e l a t i v e l y g o o d l e a d e r g r o w t h d e s p i t e t h e f o l i a g e d i s c o l o r a t i o n . F I G U R E 2 0 b . S i t k a s p r u c e e x h i b i t i n g s y m p t o m s o f K d e f i c i e n c y a f t e r f e r t i l i z a t i o n w i t h 3 0 0 k g N , 5 0 k g P a n d 5 0 k g K . F o l i a r n u t r i e n t c o n c e n t r a t i o n s (%) w e r e : N - 3 . 6 1 , P - 0 . 1 6 , K - 0 . 2 6 , C a - 0 . 2 8 , M g - 0 . 0 8 , B - 1 2 ( p p m ) , C u - 3 ( p p m ) , Z n - 2 6 (ppm), F e - 6 . 0 ( p p m ) a n d M n - 7 1 5 ( p p m ) . - 1 0 3 -t r e e s h a d f o l i a r K c o n c e n t r a t i o n s l e s s t h a n 3 . 0 % , r e l a t i v e l y -f e w a c t u a l l y h a d p u r p l i s h f o l i a g e . D e s p i t e t h e i n d u c e d K d e f i c i e n c y , g r o w t h d i d n o t a p p e a r t o b e a d v e r s e l y e f f e c t e d . T h i s may b e d u e t o t h e f a c t t h a t e v e n i n t h o s e t r e a t m e n t s w h e r e K w a s a d d e d , i t s u p t a k e w a s r e s t r i c t e d . T h u s f o l i a r K l e v e l s f o r a l l t r e a t m e n t s w e r e r e l a t i v e l y s i m i l a r , a n d t h e r e f o r e , a s s u m i n g K w a s l i m i t i n g g r o w t h , d i f f e r e n c e s b e t w e e n t r e a t m e n t s w o u l d n o t h a v e b e e n a s a p p a r e n t . H o w e v e r , t h e r e w a s e v i d e n c e w h i c h s u g g e s t e d t h a t t h e a d d i t i o n o f K w a s b e n e f i c i a l t o g r o w t h . O f t h e h i g h l y r e s p o n s i v e t r e a t m e n t s , ( i . e . : N P , N P K , a n d N P K T ) , t h o s e w h i c h m a i n t a i n e d t h e h i g h e s t f o l i a r K c o n c e n t r a t i o n s a n d c o n t e n t t e n d e d t o e x h i b i t t h e b e s t g r o w t h r e s p o n s e s . L a c k o f r e a l d i f f e r e n c e s i n g r o w t h may a l s o b e r e l a t e d t o t h e m o b i l i t y o f t h e i o n . K i s k n o w n t o b e a h i g h l y m o b i l e n u t r i e n t ( M e n g e l a n d K i r k b y , 1 9 7 9 ) , t h u s i n t e r n a l r e d i s t r i b u t i o n may h a v e b e e n s u f f i c i e n t , a t l e a s t i n t h e f i r s t g r o w i n g s e a s o n a f t e r f e r t i l i z a t i o n , t o o v e r c o m e a n y a p p a r e n t K d e f i c i e n c y . S h o u l d t h i s d e f i c i e n y p e r s i s t i n t o s u b s e q u e n t g r o w i n g s e a s o n s , i t w o u l d s e e m u n l i k e l y t h a t a c c e p t a b l e g r o w t h r a t e s c o u l d b e m a i n t a i n e d e v e n w i t h N a n d P f e r t i l i z a t i o n a l t h o u g h t h e r e h a v e b e e n c a s e s i n B r i t a i n w h e r e e x t r e m e l y l o w K l e v e l s ( 3 % ) h a v e h a d n o a p p a r e n t e f f e c t o n g r o w t h ( D i c k s o n a n d S a v i l l , 1 9 7 4 ) . A s t a t i s t i c a l a n a l y s i s o f h e m l o c k f o l i a r K l e v e l s w a s n o t d o n e b e c a u s e a l l s a m p l e s w e r e b u l k e d b y t r e a t m e n t t o g i v e o n e e s t i m a t e p e r s t a n d ( T a b l e 1 6 ) . S i m i l a r l y , n o a n a l y s i s w a s d o n e o n c e d a r , b u t p r e l i m i n a r y e s t i m a t e s b y - 1 0 4 -T A B L E 1 6 . M e a n f o l i a r K c o n c e n t r a t i o n s o f S i t k a s p r u c e a n d h e m l o c k . T r e a t m e n t s c o n n e c t e d b y t h e s a m e l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 - -a p p l i c a b l e t o s p r u c e o n l y . • S P R U C E H E M L O C K T R E A T M E N T N 3 P K N 3 P N 2 P N2 N 3 K N 2 P K N 3 N l N2K N I P N 1 P K N I K N P K T NO NOP NOK NOPK -% O V E N - D R Y W E I G H T -0 . 3 1 0 . 3 3 0 . 3 3 0 . 3 3 0 . 3 5 0 . 3 5 0 . 3 6 0 . 3 8 0 . 3 8 0 . 3 9 0 . 4 3 0 . 4 4 0 . 4 8 0 . 5 7 0 . 6 2 0 . 7 5 0 . 8 3 . 0 5 4 ) . 0 5 6 ) . 0 6 5 ) . 0 7 0 ) . 0 9 1 ) . 0 7 4 ) . 0 8 8 ) . 0 8 6 ) . 1 0 9 ) . 0 8 6 ) . 0 9 8 ) . 1 0 6 ) . 0 6 7 ) . 1 2 9 ) . 1 1 4 ) . 1 0 8 ) . 0 9 5 ) 0 . 6 2 0 . 6 0 0 . 5 8 0 . 6 1 0 . 7 7 0 . 6 6 0 . 6 8 0 . 6 0 0 . 9 0 0 . 5 8 0 . 5 9 0 . 8 3 0 . 6 5 0 . 8 1 0 . 7 2 0 . 9 1 0 . 8 7 * V a l u e s i n p a r e n t h e s i s + S D . - 1 0 5 -L e w i s ( 1 9 8 2 ) s u g g e s t e d t h a t t h e K l e v e l s o f c e d a r w e r e a d e q u a t e . I n g e n e r a l , f o l i a r K l e v e l s o f h e m l o c k w e r e ; c o n s i d e r a b l y h i g h e r t h a n t h o s e o f s p r u c e a n d n o v i s i b l e s i g n s o f K d e f i c i e n c y w e r e n o t e d . N i t r o g e n f e r t i l i z a t i o n a p p e a r e d t o d e c r e a s e K , w h i c h w a s m o r e n o t i c e a b l e i n N p l u s P f e r t i l i z e d p l o t s t h a n i n N a l o n e ; p r e s u m a b l y d u e t o a c o m b i n e d g r o w t h d i l u t i o n a n d N - a n t a g o n i s m . T h e a d d i t i o n o f K i m p r o v e d f o l i a r c o n c e n t r a t i o n s , b u t l e v e l s s t i l l r e m a i n e d b e l o w t h o s e o f t h e c o n t r o l s w h e n N w a s a p p l i e d . E f f e c t s o n F o l i a r C a l c i u m a n d M a g n e s i u m N , P a n d K f e r t i l i z a t i o n s i g n i f i c a n t l y i n f l u e n c e d f o l i a r C a a n d Mg c o m p o s i t i o n ( T a b l e 1 1 ) . I n g e n e r a l , c o n t e n t w a s i n f l u e n c e d m o r e t h a n c o n c e n t r a t i o n . N a n d P s i g n i f i c a n t l y ( p = . 0 1 ) i n c r e a s e d C a a n d Mg c o n t e n t . K h o w e v e r , w h i l e h a v i n g a p o s i t i v e e f f e c t o n C a c o n c e n t r a t i o n a n d c o n t e n t ( F i g u r e 2 1 ) , a p p e a r e d t o h a v e h a d a h i g h l y s i g n i f i c a n t a n t a g o n i s t i c e f f e c t o n Mg ( T a b l e 1 7 ) . W h i l e t h e n e g a t i v e e f f e c t s o f h i g h K c o n c e n t r a t i o n s o n Mg u p t a k e a r e w e l l k n o w n ( M e n g e l a n d K i r k b y , 1 9 7 9 ) , i t s e e m e d u n u s u a l t h a t Mg w a s d e p r e s s e d o n p l o t s w h e r e b o t h N a n d K w e r e a d d e d s i m u l t a n e o u s l y s i n c e K w a s a l s o s e v e r e l y d e p r e s s e d . A l t h o u g h s i g n i f i c a n t d i f f e r e n c e s w e r e o b s e r v e d , t h e a c t u a l d i f f e r e n c e s b e t w e e n t r e a t m e n t s w e r e s m a l l d u e t o t h e l o w Mg v a l u e ( T a b l e 1 7 ) . I n a d d i t i o n t o t h e m a i n e f f e c t s , t h e r e w e r e a l s o s i g n i f i c a n t N x P i n t e r a c t i o n s a f f e c t i n g t h e C a a n d Mg " a c o N ' - ' O c o r O ' - ' O c o M ' - ' O L o i M ' - ' O r n IX "TJ TJ TJ ~TJ ^ ^ ^ ^ TJ ~TJ TJ "D z -H 7; ^  7; l a -901--107-(g/IOOO needles) O I L . O-IOJ z o 1-< or t — LL) (J O O 2" 0 0 9 J 008. .17 L£££HD. • NO 2 Nl 3 N2 4N3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 1ZN3K 13 NOPK 14N1PK 15 N2PK 16 N3PK 17 NPKT n 1 1 1— 5-6 6-4 7-2 80 Mg CONTENT (mg/IOOO needles) 8 8 9-6 F I G U R E 22, R e l a t i o n s h i p b e t w e e n f o l i a r Mg c o n c e n t r a t i o n , c o n t e n t a n d d r y - w e i g h t . - 1 0 8 -c o n t e n t a n d Mg c o n c e n t r a t i o n ( T a b l e 1 1 ) . T h e N x P i n t e r a c t i o n o n n e e d l e n u t r i e n t c o n t e n t w a s d u e t o a g r e a t l y e n h a n c e d u p t a k e o f Mg a n d C a w h e n N a n d P w e r e a d d e d t o g e t h e r a s c o m p a r e d t o N a l o n e ( F i g u r e 2 3 ) . U p t a k e w a s g r e a t e s t a t t h e l o w e s t r a t e o f N a n d t e n d e d t o d e c l i n e a s t h e r a t e s i n c r e a s e d . T h e N x P i n t e r a c t i o n o n Mg c o n c e n t r a t i o n w a s l a r g e l y d u e t o a g r o w t h d i l u t i o n , t h i s i s c l e a r l y e v i d e n t i n F i g u r e 2 2 a s a n " A " s h i f t f o r t h o s e t r e a t m e n t s w h e r e N a n d P w e r e a d d e d s i m u l t a n e o u s l y . M e a n f o l i a r Mg a n d C a c o n c e n t r a t i o n s o f t h e S i t k a s p r u c e c o n t r o l s w e r e 0 . 1 0 % a n d 0 . 4 7 % , r e s p e c t i v e l y ( T a b l e 1 7 ) . C r i t i c a l v a l u e s f o r t h e s e t w o n u t r i e n t s h a v e n o t y e t b e e n i d e n t i f i e d f o r S i t k a s p r u c e , h o w e v e r , w h e n c o m p a r e d w i t h n u t r i e n t l e v e l s f o u n d i n g o o d a n d p o o r g r o w i n g S i t k a s p r u c e ( T a b l e 1 ) o r c r i t i c a l l e v e l s o f o t h e r s p e c i e s ( s e e M o r r i s o n , 1 9 7 4 ) , t h e v a l u e s f o r C a s e e m e d a d e q u a t e , w h e r e a s t h e v a l u e s f o r Mg w e r e l o w a n d p o s s i b l y s l i g h t l y d e f i c i e n t . F e r t i l i z e r t r i a l s w e r e n o t e s t a b l i s h e d t o s t u d y t h e e f f e c t s o f Mg s o i t i s d i f f i c u l t t o s a y i f Mg w o u l d h a v e a n y a d d i t i o n a l b e n e f i t s o n g r o w t h . Mg w a s o n l y a d d e d i n t h e N P K T t r e a t m e n t a n d a l t h o u g h i t d i d r e s u l t i n a c l e a r " C " s h i f t ( F i g u r e 2 2 ) , m e a n i n g f u l i n t e r p r e t a t i o n s c a n n o t b e d r a w n b e c a u s e o f t h e c o n f o u n d i n g e f f e c t s o f t h e o t h e r n u t r i e n t s . E x a m i n a t i o n o f t h e c l u s t e r i n g o f p o i n t s i n F i g u r e 2 2 h o w e v e r , i n d i c a t e s t h a t Mg i s n o t l i m i t i n g g r o w t h . T h i s c a n b e c o n c l u d e d b e c a u s e , a s i d e f r o m t h e a p p a r e n t a n t a g o n i s t i c e f f e c t o f K , Mg u p t a k e w a s i n c r e a s e d s i g n i f i c a n t l y . I n t h e h i g h l y r e s p o n s i v e N p l u s P t r e a t m e n t s , w h e r e c o n c e n t r a t i o n -109-FIGURE 23. E f f e c t s o f N x P i n t e r a c t i o n on Ca and Mg c o n t e n t . P o i n t s f o l l o w e d by t h e same l e t t e r a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p=.05. T A B L E 1 7 . M e a n f o l i a r C a a n d Mg c o n c e n t r a t i o n s o f S i t k a s p r u c e a n d h e m l o c k . T r e a t m e n t s c o n n e c t e d b y t h e s a m e l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p = . 0 1 — a p p l i c a b l e t o s p r u c e o n l y . T R E A T M E N T C A L C I U M • S P R U C E HEMLOCK T R E A T M E N T % O V E N - D R Y W E I G H T M A G N E S I U M * S P R U C E H E M L O C K N 2 P 0 . 4 6 ( . 1 0 0 ) NOK 0 . 4 7 ( . 1 1 9 ) NO 0 . 4 7 ( 0 . 8 3 ) N3 0 . 4 7 ( . 0 9 5 ) N2 0 . 4 7 ( . 0 8 2 ) NOP 0 . 4 8 ( . 1 0 2 ) N 3 P 0 . 4 9 ( . 0 9 1 ) N l 0 . 4 9 ( . 0 8 3 ) N 3 P K 0 . 4 9 ( . 0 9 7 ) N I P 0 . 5 0 ( . 1 0 1 ) N3K - 0 . 5 0 ( . 0 8 9 ) N 2 P K 0 . 5 1 ( . 1 1 6 ) N I K 0 . 5 1 ( . 1 0 4 ) N2K 0 . 5 2 ( . 0 9 7 ) NOPK 0 . 5 3 ( . 0 3 8 ) N P K T 0 . 5 5 ( . 0 9 6 ) N 1 P K 0 . 5 7 ( . 1 0 4 ) 0 . 3 6 0 . 3 2 0 . 3 7 0 . 3 3 0 . 3 1 0 . 3 5 0 . 3 0 0 . 3 4 0 . 2 9 0 . 3 3 0 . 2 9 0 . 3 3 0 . 3 2 0 . 3 1 0 . 3 6 0 . 3 3 0 . 2 5 N 3 P K N 2 P K NOK N2K N3K N 3 P N I K N I P NOPK N 1 P K NO N 2 P N2 NOP N l N3 N P K T 0 . 0 8 0 . 0 9 0 . 0 9 0 . 0 9 0 . 0 9 0 . 0 9 0 . 0 9 0 . 0 9 0 . 0 9 0 . 0 9 0 . 1 0 0 . 1 0 0 . 1 0 0 . 1 0 0 . 1 0 0 . 1 1 0 . 1 1 . 0 1 5 ) . 0 2 2 ) . 0 1 8 ) . 0 2 4 ) . 0 2 0 ) . 0 1 8 ) . 0 2 2 ) . 0 2 1 ) . 0 1 3 ) . 0 2 5 ) . 0 1 6 ) . 0 1 8 ) . 0 2 1 ) . 0 1 4 ) . 0 2 1 ) . 0 2 3 ) . 0 1 9 ) 0 . 0 9 0 . 1 2 0 . 1 0 0 . 1 0 0 . 1 1 0 . 1 1 0 . 1 1 0 . 1 0 0 . 1 2 0 . 1 0 0 . 1 4 0 . 0 9 0 . 0 9 0 . 1 5 0 . 1 1 0 . 1 2 0 . 0 9 V a l u e s i n p a r e n t h e s i s + S D . - I l l -d e c r e a s e d f r o m g r o w t h d i l u t i o n , t h e d e c r e a s e was n o t s i g n i f i c a n t ( T a b l e 17) and u p t a k e a p p e a r e d t o be s u f f i c i e n t t o k e e p p a c e w i t h n e e d l e e x p a n s i o n . I n f a c t , on t h e l e s s r e s p o n s i v e N a l o n e t r e a t m e n t s Mg c o n c e n t r a t i o n s i n c r e a s e d . M o r e o v e r , f o l i a r Mg c o n c e n t r a t i o n s f r o m w e l l g r o w i n g s p r u c e i n t h e HA-phase were s l i g h t l y l o w e r w i t h a mean o f 0.09%. Hemlock f o l i a g e f o r Ca and Mg was b u l k e d and o n l y a l i m i t e d a n a l y s i s was done ( T a b l e 1 7 ) . I n g e n e r a l , f e r t i l i z a t i o n a p p e a r e d t o have l i t t l e o r no e f f e c t on Ca c o n c e n t r a t i o n s , h o w e v e r , Mg c o n c e n t r a t i o n s were d e p r e s s e d . P r e s u m a b l y t h i s d e p r e s s i o n was due t o a c o m b i n e d e f f e c t o f a n t a g o n i s m f r o m t h e K i o n and g r o w t h d i l u t i o n s . As i n s p r u c e , P a p p e a r e d t o have e n h a n c e d Mg u p t a k e . O t h e r s t u d i e s h ave a l s o n o t e d a s i m i l a r e f f e c t o f P on Mg u p t a k e ( s e e F i e d l e r e t a l . , 1 9 8 3 ) . Mg c o n c e n t r a t i o n o f h e m l o c k i n . t h e c o n t r o l p l o t s were c o n s i d e r a b l y h i g h e r t h a n t h o s e o f s p r u c e and w o u l d n o t be c o n s i d e r e d d e f i c i e n t ( B a l l a r d and C a r t e r , 1 9 8 3 ) . E f f e c t s o f F o l i a r S u l f u r Mean f o l i a r S c o n c e n t r a t i o n s o f t h e c o n t r o l t r e e s was 0.06%. W h i l e d e f i c i e n c y l e v e l s f o r S i t k a s p r u c e have n o t been i d e n t i f i e d , L e a f ( 1 9 6 7 ) n o t e d t h a t f o l i a r S c o n c e n t r a t i o n s l e s s t h a n 0.13% f o r P i c e a a b i e s was c o n s i d e r e d d e f i c i e n t . B a l l a r d and C a r t e r ( 1 9 8 2 ) s u g g e s t e d t h a t when N was d e f i c i e n t , t h e N/S r a t i o s h o u l d n o t e x c e e d a v a l u e d e t e r m i n e d by t h e e q u a t i o n , 4.2X + 4.94, w here X i s t h e p e r c e n t f o l i a r N c o n c e n t r a t i o n . U s i n g t h e d a t a f r o m t h e - 1 1 2 -p r e s e n t s t u d y , t h e e q u a t i o n y i e l d s a v a l u e o f 8 . 4 9 , w h e r e a s t h e N / S r a t i o w a s 1 3 . 2 8 . T h e s e f i n d i n g s s u g g e s t a S d e f i c i e n c y o r p o s s i b l y a N - i n d u c e d S d e f i c i e n c y may e x i s t ( B a l l a r d a n d C a r t e r , 1 9 8 3 ) a n d t h e s t a n d s s h o u l d r e s p o n d t o b o t h N a n d S f e r t i l i z a t i o n ( B a l l a r d , T . M . , 1 9 7 9 ) . A s w i t h M g , i t i s d i f f i c u l t t o s a y i f t h e s e s t a n d s h a v e r e s p o n d e d f a v o u r a b l y t o S f e r t i l i z a t i o n a s S w a s o n l y a d d e d i n t h e N P K T t r e a t m e n t . A l t h o u g h t h e r e w a s a c l e a r " C " s h i f t i n F i g u r e 2 4 , i n t e r p r e t a t i o n s a r e c o n f o u n d e d b y t h e o t h e r n u t r i e n t s . R e c e n t f e r t i l i z e r t r i a l s e s t a b l i s h e d b y B C F P ( s e e p a g e 9 0 ) f o u n d d i a m e t e r r e s p o n s e o f h e m l o c k t o b e 1 9 % , 3 9 % a n d 4 4 % f o r u r e a , a m m o n i u m s u l p h a t e a n d a m m o n i u m n i t r a t e , r e s p e c t i v e l y . A g a i n , i t i s d i f f i c u l t t o s a y i f t h e i m p r o v e d r e s p o n s e o f a m m o n i u m s u l p h a t e o v e r u r e a i s d u e t o t h e s u l f u r o r t o t h e p o s s i b i l i t y o f u r e a h a v i n g d e t r i m e n t a l e f f e c t s o n h e m l o c k a s s u g g e s t e d b y G i l l a n d L a v e n d e r ( 1 9 8 3 a ) . T h e l a t t e r s e e m e d m o r e l i k e l y b e c a u s e a m m o n i u m n i t r a t e h a d t h e g r e a t e s t r e s p o n s e . R e c e n t s t u d i e s b y T u r n e r e t a l . ( 1 9 7 7 ) h o w e v e r , f o u n d t h a t m u c h o f t h e v a r i a t i o n i n t h e r e s p o n s e o f D o u g l a s - f i r t o N f e r t i l i z a t i o n i n t h e P a c i f i c N o r t h w e s t c o u l d b e e x p l a i n e d b y f o l i a r s u l p h a t e l e v e l s . T h o s e s t a n d s s h o w i n g t h e h i g h e s t r e s p o n s e s t e n d e d t o a l s o h a v e t h e h i g h e s t f o l i a r s u l p h a t e r e s e r v e s . T h e b a s i s f o r i m p r o v e d r e s p o n s e l a y i n t h e b i o c h e m i c a l r e l a t i o n s h i p b e t w e e n N a n d S i n p r o t e i n s y n t h e s i s ( T u r n e r e t a l . , 1 9 7 7 ) a n d s u g g e s t s t h a t S d e f i c i e n c i e s may b e m o r e p r e v a l e n t i n t h e P a c i f i c N o r t h w e s t t h a n o r i g i n a l l y a n t i c i p a t e d . E I I -- 1 1 4 -I m p o v e m e n t o f t h e n u t r i t i o n a l s t a t u s o f t h e t r e e s a p p e a r e d t o h a v e r e s u l t e d i n a s u b s t a n t i a l i m p r o v e m e n t i n t h e t r e e s ' S n u t r i t i o n e v e n t h o u g h S w a s n o t a d d e d . T h i s i s c l e a r l y e v i d e n t i n F i g u r e 2 4 . M e a n f o l i a r S c o n c e n t r a t i o n s i n c r e a s e d t o 0 . 0 8 % w h e n N a l o n e w a s a d d e d a n d t o 0 . 1 3 % w h e n N a n d P w e r e a d d e d t o g e t h e r . S i n c e c o n t r o l t r e e s w e r e h i g h l y d e f i c i e n t i n N a n d P a n d g r o w t h w a s e x t r e m e l y p o o r , d e m a n d f o r o t h e r n u t r i e n t s s u c h a s S may h a v e b e e n l i m i t e d e v e n t h o u g h a v a i l a b l e s u l p h a t e i n d i c e s w e r e h i g h . T h i s w o u l d b e s o m e w h a t a n a l o g o u s t o t h e " B " s h i f t i l l u s t r a t e d i n F i g u r e 2 . T h e i n c r e a s e i n S c o n c e n t r a t i o n s h o w e v e r , may a l s o b e r e l a t e d t o i n c r e a s e s i n S m i n e r a l i z a t i o n a s a r e s u l t o f N a n d P f e r t i l i z a t i o n . R e c e n t s t u d i e s h a v e s h o w n m i n e r a l i z a i o n o f o r g a n i c m a t t e r i s a n i m p o r t a n t s o u r c e o f s u l p h a t e f o r t r e e s p e c i e s ( D a v i e s e t a l . , 1 9 8 3 ) . M e a n f o l i a r S c o n c e n t r a t i o n i n t h e t r e e s s a m p l e d f r o m t h e H A - p h a s e w e r e 0 . 1 3 % a n d 0 . 1 5 % f o r s p r u c e a n d h e m l o c k , r e s p e c t i v e l y . T h e h i g h e r f o l i a r S l e v e l s h e r e may b e d u e t o t h e m o r e " a c t i v e " o r g a n i c m a t t e r o f t h i s p h a s e a s i n d i c a t e d b y t h e g r e a t e r r a t e s o f N m i n e r a l i z a t i o n . A s s u l f u r i n p u t s a n d o u t p u t s w e r e n o t i n v e s t i g a t e d i n t h i s s t u d y i t i s n o t p o s s i b l e t o s a y w h y f o l i a r S c o n c e n t r a t i o n s i n c r e a s e d . I n a n y e v e n t , i t a p p e a r s t h a t S d e f i c i e n c i e s c a n b e o v e r c o m e t h r o u g h e n h a n c e d u p t a k e a f t e r N p l u s P f e r t i l i z a t i o n . I f S i s i n d e e d d e f i c i e n t , a n a l t e r n a t e s o u r c e o f N s u c h a s a m m o n i u m s u l p h a t e may p r o v e t o b e s u p e r i o r . -115-E f f e c t s on F o l i a r M i c r o - n u t r i e n t s A p p l i c a t i o n of m i c r o - n u t r i e n t s i n the NPKT tr e a t m e n t r e s u l t e d i n an i n c r e a s e i n the f o l i a r c o n c e n t r a t i o n and c o n t e n t of a l l a p p l i e d n u t r i e n t s except Zn ( F i g u r e s 25 to 2 8 ) . In the case of Zn, c o n c e n t r a t i o n decreased but c o n t e n t i n c r e a s e d ( F i g u r e 2 8 ) . Because o n l y l i m i t e d a t t e n t i o n was p a i d to the m i c r o - n u t r i e n t s i n t h i s s t u d y , p r e c i s e i n t e r p r e t a t i o n of the f o l i a r a n a l y s i s was not p o s s i b l e . In a d d i t i o n , r e l a t i v e l y l i t t l e a t t e n t i o n has been p a i d to m i c r o - n u t r i e n t f e r t i l i z a t i o n e l sewhere and thus comparisons w i t h o t h e r t r i a l s are l i m i t e d . Many o r g a n i c s o i l s however, are known to be d e f i c i e n t i n m i c r o - n u t r i e n t s , and i n p a r t i c u l a r Cu and B ( V e i j a l a i n e n , 1977). F e r t i l i z e r t r i a l s w i t h m i c r o - n u t r i e n t s on p e a t l a n d s i n S c a n d i n a v i a n c o u n t r i e s , o f t e n r e s u l t i n an i n c r e a s e i n f o l i a r c o n c e n t r a t i o n of the c o r r e s p o n d i n g n u t r i e n t s ( V e i j a l a i n e n , 1977) and an improved growth response over p l o t s r e c e i v i n g N, P and K f e r t i l i z e r s o n l y ( V e i j a l a i n e n , 1981). Other s t u d i e s on m i c r o - n u t r i e n t s have i d e n t i f i e d f o l i a r c o n c e n t r a t i o n s a s s o c i a t e d w i t h good and poor growth f o r v a r i o u s t r e e s p e c i e s ( T a b l e 18). Such v a l u e s must be compared w i t h c a u t i o n because of the wide v a r i a t i o n e n c o u n t e r e d . In g e n e r a l , i t appears as i f B, Mn and Zn are adequate, whereas, Cu and " a c t i v e " Fe are low. However, g i v e n the range of v a l u e s i n T a b l e 18 i t i s d e b a t a b l e whether Cu i s a c t u a l l y d e f i c i e n t . Cu l e v e l s i n the HA-phase, w h i l e h i g h e r , c o u l d s t i l l be c o n s i d e r e d low a t 4.6 ppm and yet -116-251 (g/IOOO needles) 24 23L 22L E ex. CL 21 U J u 8 O l C Q I8L I7L 16 / / / JL 7 8 9 10 II B CONTENT (mg/IOOO needles) 12 13 FIGURE 25. R e l a t i o n s h i p between f o l i a r B c o n c e n t r a t i o n , content and dry-weight. -117-Cg/IOOO needles) £ CL CL < cn r -U J <_> z o o r j O / LEGEND • NO 2 Nl 3N2 4N3 17 NPKT 2 3 4 Cu CONTENT (mg/1000 needles) FIGURE 26. R e l a t i o n s h i p b e t w e e n f o l i a r Cu c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t . 0.18_ ^ 0.17. O h-UJ o z o u 0. J6_ / 0.15. / / 0.1' (g/1000 needles) T T T T 5.6 6.4 7.2 8.0 8.8 9.6 10.4 Mn CONTENT (mg/IOOO needles) 11.2 FIGURE 27, R e l a t i o n s h i p between f o l a i r Mn c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t . LEGEND • NO 2 N l 3 N2 4 N 3 17 NPKT 1 12.0 oo i -119-(g/IOOO needles) Zn CONTENT (mg/IOOO needles) FIGURE 28. R e l a t i o n s h i p b e t w e e n f o l i a r Zn c o n c e n t r a t i o n , c o n t e n t and d r y - w e i g h t . - 1 2 0 -t h e r e i s n o e v i d e n c e , i n t e r m s o f g r o w t h o r v i s u a l s y m p t o m s , t o s u g g e s t a d e f i c i e n c y e x i s t s . A c t i v e F e , a s o p p o s e d t o t o t a l F e , w a s c o n s i d e r e d i n t h i s s t u d y s i n c e B a l l a r d ( 1 9 8 1 ) s u g g e s t e d t h a t i t may b e m o r e v a l u a b l e a s a d i a g n o s t i c i n d i c a t o r . I t i s t h e F e t h a t i s t h e o r e t i c a l l y a c t i v e i n t h e f o r m a t i o n o f c h l o r o p h y l l ( O s e r k o w s k y , 1 9 3 3 ) . A c o n c e n t r a t i o n o f l e s s t h a n 3 0 ppm a c t i v e F e i s b e l i e v e d t o i n d i c a t e a p r o b a b l e F e d e f i c i e n c y f o r s e v e r a l s p e c i e s ( B a l l a r d a n d C a r t e r , 1 9 8 3 ) . T h i s w o u l d s u g g e s t t h a t t h e S i t k a s p r u c e i n t h i s s t u d y , w i t h a m e a n F e c o n c e n t r a t i o n o f 6 . 1 p p m , w a s s u f f e r i n g f r o m a s e v e r e F e d e f i c i e n c y , e v e n m o r e s o t h a n N o r P . H o w e v e r , t h i s s e e m s u n l i k e l y s i n c e v i g o u r o u s l y g r o w i n g s p r u c e a n d h e m l o c k i n t h e H A - p h a s e h a d c o m p a r a b l e c o n c e n t r a t i o n s ( T a b l e 1 8 ) a n d y e t s h o w e d n o s i g n s o f d e f i c i e n c y . T h e l i m i t e d f o l i a r a n a l y s i s d o n e b y L e w i s ( 1 9 8 2 ) f o u n d t o t a l F e c o n c e n t r a t i o n s t o r a n g e b e t w e e n 1 5 a n d 3 0 ppm f o r s p r u c e w h i c h i s a l s o c o n s i d e r e d l o w a n d p o s s s i b l y d e f i c i e n t ( B a l l a r d a n d C a r t e r , 1 9 8 3 ) . T h u s t h e r e i s t h e p o s s i b i l i t y t h a t a m o d e r a t e F e d e f i c i e n c y m a y e x i s t . N u m e r o u s e x a m p l e s o f a n t a g o n i s t i c e f f e c t s o n f o l i a r m i c r o - n u t r i e n t s f o l l o w i n g m a c r o - n u t r i e n t f e r t i l i z a t i o n h a v e b e e n o b s e r v e d ( S m i t h , 1 9 6 2 ; O l s e n , 1 9 7 2 ; V e i j a l a i n e n , 1 9 7 7 ) . A l i m i t e d a n a l y s i s u s i n g f o l i a g e f r o m t h e N o n l y a n d t h e N p l u s P p l o t s o f t h e " p h o s p h o r u s " t r i a l w a s d o n e t o i n v e s t i g a t e a n y p o s s i b l e a n t a g o n i s t i c e f f e c t s . T h e o n l y a p p a r e n t a n t a g o n i s t i c e f f e c t s w a s a n e g a t i v e e f f e c t o f N a n d P o n Z n a n d P o n B . I n g e n e r a l i t a p p e a r s a s i f u p t a k e o f - 1 2 1 -TABLE 18. Comparison of f o l i a r micro-nutrient concentrations with estimates from Literature. A l l values are in ppm. -LITERATURE VALUES- -THIS STUDY-DOUGLAS-FIR NORWAY SPRUCE WESTERN HEMLOCK SITKA SPRUCE CH-PHASE SITKA SPRUCE HA-PHASE SITKA WESTERN NUTRIENT •ADEQUATE DEFICIENT ADEQUATE DEFICIENT ADEQUATE DEFICIENT ADEQUATE DEFICIENT CONTROL FERTILIZED SPRUCE HEMLOCK Cu 1.5 2, 4.2-5.9 1.1 2.4-3.9 0.7-4.23 - 3.9-4. l' - 7.0-10.8 4.5-6.61 1.5 2.3-2.8 2.9 4.6 4.6 5.1 B 9-161 5 10-253 6-84 171 5 17-281 - 16.3 16.7 19.1 24.5 Fe (total) 39-511 - - - 35-59* - - - 15-305 - 15-615 46-925 Fe (active) - - - - - - - - 6.1 6.9 5.7 7.3 Mn 390-12941 - 300-23001 - 1583-18761 - 1598-2043* - 1355 1439 1374 1663 Zn _ _ _ 42-571 _ 47 46 41 28 Adequate represents concentrations found in trees exhibiting good growth. Sources: 1. Stone, 1967. 2. Binns et a l . , 1980. 3. Braekke, 1979. 4. Silfverberg, 1980. 5. Lewis, 1982. - 1 2 2 -C u , Mn a n d B w e r e a l l e n h a n c e d b y N f e r t i l i z a t i o n ( F i g u r e s 2 5 t o 2 7 ) . - 1 2 3 -SUMMARY AND C O N C L U S I O N S F e r t i l i z a t i o n s i g n i f i c a n t l y i n c r e a s e d f i r s t - y e a r l e a d e r g r o w t h , c u r r e n t y e a r n e e d l e d r y - w e i g h t a n d n e e d l e n u t r i e n t c o m p o s i t i o n . T h e r e w e r e a n u m b e r o f h i g h l y s i g n i f i c a n t i n t e r a c t i o n s , u s u a l l y N x P , w h i c h i n f l u e n c e d t h e a b o v e r e s p o n s e s . A l t h o u g h N a l o n e o r i n c o m b i n a t i o n w i t h K h a d a p o s i t i v e e f f e c t o n b o t h n e e d l e w e i g h t a n d l e a d e r g r o w t h , t h e a d d i t i o n o f P h a d a s t r o n g s y n e r g i s t i c e f f e c t w h e n a p p l i e d w i t h N a n d r e s u l t e d i n a 2 7 % a n d 4 1 % i n c r e a s e i n l e a d e r g r o w t h a n d n e e d l e w e i g h t , r e s p e c t i v e l y , o v e r t h a t o f N a l o n e . S i m i l a r , a l t h o u g h s o m e w h a t g r e a t e r r e s p o n s e p a t t e r n s w e r e n o t e d f o r h e m l o c k . F e r t i l i z a t i o n w i t h N r e s u l t e d i n a d r a m a t i c i n c r e a s e i n f o l i a r N c o n c e n t r a t i o n s , w e l l i n e x c e s s o f t h e o p t i m u m f o r s p r u c e . A s a r e s u l t , t h e r e t e n d e d t o b e a p r o g r e s s i v e d e c l i n e i n r e s p o n s e w i t h i n c r e a s i n g r a t e s o f N a p p l i c a t i o n . N a l s o h a d a s t r o n g a n t a g o n i s t i c e f f e c t o n K c o n c e n t r a t i o n s t o t h e e x t e n t t h a t a s e v e r e K d e f i c i e n c y w a s i n d u c e d i n a l l p l o t s r e c e i v i n g N w h e t h e r K w a s a d d e d o r n o t . A s i m i l a r e f f e c t w a s n o t n o t e d f o r P , C a o r M g . A l t h o u g h t h e d e s i g n d i d n o t a d e q u a t e l y t e s t a l l n u t r i e n t s , t h e m e t h o d s u s e d w e r e u s e f u l i n i n t e r p r e t i n g f o l i a r a n a l y s i s a n d i d e n t i f y i n g p o t e n t i a l l y l i m i t i n g -124-n u t r i e n t s and r e s p o n s i v e t r e a t m e n t s . B a s e d on t h e i n t e r p r e t a t i o n o f t h e r e s u l t s , t h e f o l l o w i n g c o n c l u s i o n s c a n be d r a w n : ( 1 ) N and P a r e s e v e r e l y d e f i c i e n t i n b o t h s p r u c e and h e m l o c k and a r e p a r t l y r e s t i c t i n g g r o w t h . C e d a r , w h i l e h a v i n g s u f f i c i e n t P, a p p e a r s t o have a m o d e r a t e N d e f i c i e n c y . ( 2 ) K i s p r e s e n t l y m o d e r a t e l y d e f i c i e n t i n s p r u c e , b u t , a s e v e r e N - i n d u c e d K d e f i c i e n c y i s l i k e l y i f an N f e r t i l i z a t i o n p r o g r a m i s u n d e r t a k e n w i t h o u t a d d i t i o n a l K. ( 3 ) Of o t h e r n u t r i e n t s t e s t e d , S, Cu and Fe r e m a i n q u e s t i o n a b l e a s t o t h e i r a d e q u a c y . F u r t h e r t e s t i n g i s r e q u i r e d , p a r t i c u l a r l y w i t h r e s p e c t t o S; i t i s t h e o n l y e l e m e n t o f t h e t h r e e where l a r g e d i f f e r e n c e s i n f o l i a r c o n c e n t r a t i o n s b e t w e e n t h e two p h a s e s were n o t e d . I n a d d i t i o n t o t h e s e t h r e e e l e m e n t s h o w e v e r , f u r t h e r t e s t i n g o f K and d i f f e r e n t t y p e s o f N f e r t i l i z e r s s h o u l d a l s o be c o n s i d e r e d . ( 4 ) C h a nges i n n e e d l e w e i g h t and f i r s t - y e a r l e a d e r g r o w t h r e s p o n s e s s u g g e s t t h a t b o t h s p r u c e and h e m l o c k w i l l be h i g h l y r e s p o n s i v e t o N and P f e r t i l i z a t i o n . A l t h o u g h some r e s p o n s e t o N a l o n e i s p o s s i b l e , a d d i t i o n a l g r o w t h b e n e f i t s f r o m P s u g g e s t t h a t e c o n o m i c a l g a i n s c a n o n l y be o b t a i n e d by N and P t o g e t h e r . No b e n e f i t s were a p p a r e n t f r o m K, b u t t h e i n d u c e d d e f i c i e n c y may h a v e a n e g a t i v e i m p a c t i n s u b s e q u e n t y e a r s . S i n c e no g r o w t h e s t i m a t e f o r c e d a r were d e t e r m i n e d , i t i s unknown how t h i s s p e c i e s w i l l r e s p o n d , h o w e v e r , t h e p o s i t i v e c h a n g e s i n t h e f o l i a r n u t r i e n t c o n c e n t r a t i o n s a f t e r f e r t i l i z a t i o n s u g g e s t t h a t i t a l s o w i l l r e s p o n d f a v o u r a b l y t o f e r t i l i z a t i o n . ( 5 ) A l l f i v e p l a n t a t i o n s r e s p o n d e d s i m i l a r l y i n d i c a t i n g t h a t t h e r e s u l t s f r o m t h i s s t u d y w i l l be a p p l i c a b l e t o o t h e r p l a n t a t i o n s e s t a b l i s h e d on t h e CH-phase. ( 6 ) F u r t h e r f e r t i l i z a t i o n t r i a l s a r e r e q u i r e d t o q u a n t i f y r e s p o n s e s and d e t e r m i n e t h e i r e c o n o m i c v i a b i l i t y . However, r e s u l t s o f t h i s s t u d y s u g g e s t t h a t , u n d e r o p e r a t i o n a l c o n d i t i o n s , an i n i t i a l f e r t i l i z e r a p p l i c a t i o n o f 200 kg N/ha, 75 kg P/ha and 125 kg K/ha a p p e a r s t o be optimum. -125-GENERAL CONCLUSIONS The p o o r g r o w t h o f S i t k a s p r u c e and w e s t e r n h e m l o c k on t h e CH-phase o f t h e s a l a l - m o s s e c o s y s t e m a s s o c i a t i o n c a n be a t t r i b u t e d t o m u l t i p l e n u t r i e n t d e f i c i e n c i e s , and i n p a r t i c u l a r , N and P. I n a d d i t i o n , t h e r e was a p o s s i b l e S and K d e f i c i e n c y . M o r e o v e r , a s e v e r e K d e f i c i e n c y was a l s o i n d u c e d by N f e r t i l i z a t i o n . D e s p i t e t h i s N i n d u c e d d e f i c i e n c y h o w e v e r , no a p p a r e n t g r o w t h b e n e f i t s f r o m K f e r t i l i z a t i o n were e v i d e n t . W i t h t h e e x c e p t i o n o f m i n e r a l i z a b l e N, t h e d r a m a t i c d i f f e r e n c e i n p r o d u c t i v i t y b e t w e e n t h e two p h a s e s does n o t a p p e a r t o be a r e f l e c t i o n o f d i f f e r e n c e s i n s o i l n u t r i e n t c o n t e n t . E v e n i n t h e c a s e o f m i n e r a l i z a b l e N, r e l a t i v e l y h i g h amounts were r e l e a s e d d u r i n g t h e i n c u b a t i o n o f s a m p l e s f r o m t h e n o n - p r o d u c t i v e CH-phase. The h i g h amounts o f N f o u n d i n t h e i n c u b a t e d s a m p l e s r a i s e s q u e s t i o n s as t o t h e v a l i d i t y o f u s i n g m i n e r a l i z a b l e N a s a m e a s u r e o f N a v a i l a b i l i t y on t h e s e s i t e s . H owever, t h e f a c t t h a t c e d a r had r e l a t i v e l y h i g h f o l i a r N c o n c e n t r a t i o n s and e x h i b i t e d good g r o w t h s u g g e s t e d an a d e q u a t e s u p p l y o f N was a v a i l a b l e . M o st s t u d i e s on N m i n e r a l i z a t i o n and i t s r e l a t i o n s h i p t o t r e e g r o w t h have u s e d m i n e r a l s o i l when d e t e r m i n i n g m i n e r a l i z a t i o n r a t e s . On s i t e s w i t h t h i c k o r g a n i c a c c u m u l a t i o n s , s u c h as t h o s e f o u n d i n t h e -126-CH-phase, f u r t h e r r e s e a r c h i s r e q u i r e d i n t o the r e l a t i o n s h i p s between N m i n e r a l i z a t i o n r a t e s , N a v a i l a b i l i t y , and t r e e growth before the r e s u l t s from i n c u b a t i o n s t u d i e s on these s i t e s can be i n t e r p r e t e d with c o n f i d e n c e . In a d d i t i o n to, d i f f e r e n c e s i n s o i l n u t r i e n t s , other f a c t o r s , such as a s a l a l e f f e c t and/or d i f f e r e n c e s i n s o i l p h y s i c a l p r o p e r t i e s , must be considered as p o s s i b l e c o n t r i b u t i n g agents to the d e c l i n e of these p l a n t a t i o n s . E r a d i c a t i o n of s a l a l and a m e l i o r a t i o n of s i t e c o n d i t i o n s through s c a r i f i c a t i o n have been suggested as an a l t e r n a t i v e to f e r t i l i z a t i o n f o r the management of these s i t e s . However, the b e n e f i t s d e r i v e d from s c a r i f i c a t i o n may not l a s t the e n t i r e r o t a t i o n and subsequent f e r t i l i z a t i o n with N may be necessary to maintain s i t e p r o d u c t i v i t y . In a d d i t i o n , s c a r i f i c a t i o n while i n c r e a s i n g N a v a i l a b i l i t y on these s i t e s , may have only a modest or even a negative i n f l u e n c e on the a v a i l a b i l i t y of other n u t r i e n t s . Improvement i n the N n u t r i t i o n without a corresponding improvement i n the P n u t r i t i o n may only compound the present P d e f i c i e n c y . T h e r e f o r e , f e r t i l i z a t i o n must be considered as an i n t e g r a l part of the o v e r a l l management regime s e l e c t e d f o r these s i t e s . A l l the evidence of t h i s study suggest that spruce, hemlock and i n a l l l i k e l i h o o d , cedar, w i l l be h i g h l y r e s p o n s i v e to N and P f e r t i l i z a t i o n . Despite the l a c k of response to K, any f e r t i l i z a t i o n program undertaken on these s i t e s should a l s o i n c l u d e t h i s element s i n c e a severe d e f i c i e n c y i s r e a d i l y induced by N. -127-At present, the methods used i n t h i s study only allow a q u a l i t a t i v e estimate of the p o t e n t i a l responsiveness of these p l a n t a t i o n s . In order to q u a n t i f y the response and determine whether or not f e r t i l i z a t i o n w i l l be economically v i a b l e , c o n v e n t i o n a l f e r t i l i z e r t r i a l s must be e s t a b l i s h e d and t h e i r development f o l l o w e d . The r e s u l t s of t h i s study however, have narrowed c o n s i d e r a b l y , those treatments which should be considered i n subsequent f e r t i l i z e r t r i a l s . Moreover, i t has been shown that the p l a n t a t i o n s of the CH-phase e x h i b i t very s i m i l a r response p a t t e r n s , thus the r e s u l t s of t h i s and other s t u d i e s should be a p p l i c a b l e to other p l a n t a t i o n s e s t a b l i s h e d on the CH-phase. Not a l l of the o b j e c t i v e s of t h i s study have been met s i n c e some elements such as S and K, as w e l l as, other sources and r a t e s of N r e q u i r e f u r t h e r t e s t i n g . In a d d i t i o n , more quest i o n s were r a i s e d than p o s s i b l y were answered. While i t has been shown that f e r t i l i z a t i o n i s a promising s i l v i c u l t u r a l management t o o l f o r p l a n t a t i o n s e s t a b l i s h e d on the CH-phase, more resea r c h i s r e q u i r e d , not only i n t o the n u t r i t i o n a l aspects of these p o t e n t i a l l y h i g h l y p r o d u c t i v e s i t e s , but a l s o i n t o the processes r e s p o n s i b l e f o r t h e i r development. - 1 2 8 -LITERATURE CITED Adams, M.A., and P.M. A t w i l l . 1982. N i t r a t e r e d u c t a s e a c t i v i t y and g r o w t h r e s p o n s e o f f o r e s t s p e c i e s t o ammonium and n i t r a t e s o u r c e s o f n i t r o g e n . P l a n t and S o i l 66: 373 -3 8 1 . A n d e r s o n , S., R . J . Z a s o s k i , and S.P. G e s s e l . 1982. P h o s p h o r u s and l i m e r e s p o n s e o f S i t k a s p r u c e , w e s t e r n h e m l o c k s e e d l i n g s , and r o m a i n e l e t t u c e on two c o a s t a l W a s h i n g t o n s o i l s . Can. J . F o r . R e s . 12: 985 - 9 9 1 . A t k i n s o n , W.A. 1 975. F o r e s t f e r t i l i z a t i o n r e s e a r c h and l a n d u s e p l a n n i n g i m p l i c a t i o n s — t h e w e s t e r n U n i t e d S t a t e s . I_n: F o r e s t e r s i n l a n d - u s e p l a n n i n g . P r o c . S o c . Am. F o r . pp. 199 - 220. A t t e r s o n , J . , and W.O. B i n n s . 1975. P e a t n u t r i e n t s and t r e e r e q u i r e m e n t s i n f o r e s t r y c o m m i s s i o n p l a n t a t i o n s . I_n: P e a t l a n d F o r e s t r y ; P r o c , N a t u r a l E n v i r o n m e n t R e s e a r c h C o u n c i l . pp. 127 - 137. A u s t i n , R.C., and R.E. S t r a n d . 1960. The use o f s l o w l y s o l u b l e f e r t i l i z e r s i n f o r e s t p l a n t i n g i n t h e P a c i f i c N o r t h w e s t . J . F o r . 58: 619 - 6 2 7 . B a k e r , J . 1970. Some e f f e c t s o f u r e a f e r t i l i z a t i o n on s o i l c h a r a c t e r i s t i c s and t i s s u e m i n e r a l c o n t e n t i n o v e r s t o c k e d w e s t e r n h e m l o c k s t a n d s . Can. F o r . S e r v . I n f . Rep. BC-X-39. B a l l a r d , R. 1978, E f f e c t o f f i r s t - r o t a t i o n p h o s p h o r u s a p p l i c a t i o n s on f e r t i l i z e r r e q u i r e m e n t s o f s e c o n d - r o t a t i o n R a d i a t a p i n e . N.Z. J . F o r . S c i . 8: 135 - 145. B a l l a r d , R. 1979, The means t o e x c e l l e n c e t h r o u g h n u t r i e n t amendment. L n : F o r e s t P l a n t a t i o n s : t h e shape o f t h e f u t u r e . W e y e r h a e u s e r S c i . Symp. pp. 159 - 200. - 1 2 9 -B a l l a r d , T.M. 1979. I n t e r i m o p e r a t i o n a l g u i d e l i n e s f o r f o r e s t f e r t i l i z a t i o n i n t h e K a m l o o p s F o r e s t D i s t r i c t . C o n t r a c t R e p o r t t o t h e M i n i s t r y o f F o r e s t s , V i c t o r i a , B.C. 28 pp. B a l l a r d , T.M. 1981. F o l i a r A n a l y s i s R e s e a r c h . C o n t r a c t R e p o r t t o t h e M i n i s t r y o f F o r e s t s , V i c t o r i a , B.C. 112 pp. B a l l a r d , T.M. 1982. M a n u a l f o r f o r e s t s o i l s . M imeo-Dept. S o i l S c i . , UBC, V a n c o u v e r , B. C. B a l l a r d , T.M., and R.E. C a r t e r . 1983. E v a l u a t i n g f o r e s t s t a n d n u t r i e n t s t a t u s . M i n i s t r y o f F o r e s t s , V i c t o r i a , B. C. B a r k e r , A.V., D.N. M a y n a r d , and W.H. Lachman. 1967. I n d u c t i o n o f t o m a t o s t e m and l e a f l e s i o n and K d e f i c i e n c y by e x c e s s i v e NH4+ n u t r i t i o n . S o i l S c i . 193: 319 -327. B e e v e r s , L., and R.H. Hageman. 1969. N i t r a t e r e d u c t i o n i n h i g h e r p l a n t s . Annu. Rev. P l a n t P h y s i o l . 20: 495 - 522. B e e v e r s , L., and R.H, B e n z i a n , B. 1965. B e r g , B., B. Wessen, , Hageman. 1983. U p t a k e and r e d u c t i o n o f n i t r a t e : b a c t e r i a and h i g h e r p l a n t s . I_n: A L a u c h l i and R.L. B i e l e s k i ( e d s . ) . I n o r g a n i c p l a n t n u t r i t i o n . E n c y c l o p e d i a o f P l a n t P h y s i o l o g y , New S e r i e s Volume 15A, S p r i n g e r - V e r l a g , B e r l i n . pp. 351 -3 7 5 . E x p e r i m e n t s on n u t r i t i o n a l p r o b l e m s i n f o r e s t n u r s e r i e s : Volume I . G.B. F o r . Comm. B u l l . No. 37. 251 pp. and G. Ekbohm. 1982. N i t r o g e n l e v e l and d e c o m p o s i t i o n i n S c o t s p i n e n e e d l e l i t t e r . O i k o s 38: 291 - 296. B e r g , B., and G.E. Ekbohm. 1983. N i t r o g e n i m m o b i l i z a t i o n i n d e c o m p o s i n g n e e d l e l i t t e r a t v a r i a b l e c a r b o n / n i t r o g e n r a t i o s . E c o l o g y 64: 63 - 67. B i g g , W.L., and T.W. D a n i e l . 1978. E f f e c t s o f n i t r a t e , ammonium and pH on t h e g r o w t h o f c o n i f e r s e e d l i n g s and t h e i r p r o d u c t i o n o f n i t r a t e r e d u c t a s e . P l a n t and S o i l 50: 371 - 385. - 1 3 0 -B i n n s , W . O . 1 9 7 5 . B i n n s , W . O . , and J , B i n n s , W . O . G . J , B l y t h , J . F . , and D .A , B o n n e a u , M. 1973, B r a d l y , R . T . 1971 B r a e k k e , F . H . 1979 , F e r t i l i z e r s i n t h e f o r e s t s : a g u i d e t o m a t e r i a l s . G . B . F o r . Comm. L e a f l e t N o . 6 3 . 14 p p . A t t e r s o n . 1 9 6 7 . N u t r i t i o n o f f o r e s t c r o p s . Ijn: R e p o r t on f o r e s t r e s e a r c h f o r t h e y e a r e n d i n g M a r c h , 1 9 6 7 . G . B . F o r . Comm. p p . 48 - 5 3 . M a y h e a d , and J . M . M a c k e n z i e . 1 9 8 0 . N u t r i e n t d e f i c i e n c i e s o f c o n i f e r s i n B r i t i s h f o r e s t s : An i l l u s t r a t e d g u i d e . G . B . F o r . Comm. L e a f l e t N o . 7 6 . 22 p p . M a c l e o d . 1 9 8 1 . S i t k a s p r u c e i n N o r t h - E a s t S c o t l a n d . I. R e l a t i o n s h i p b e t w e e n s i t e f a c t o r s and g r o w t h . F o r e s t r y 5 4 : 41 - 6 2 . S t a t e R e s e a r c h on f o r e s t n u t r i t i o n . I n : I n t e r n a t i o n a l s y m p o s i u m on f o r e s t f e r t i l i z a t i o n . F A 0 - I U F R 0 , P a r i s , p p . 1 - 2 3 . T h i n n i n g c o n t r o l i n B r i t i s h W o o d l a n d s ( M e t r i c ) . G . B . F o r . Comm. B o o k l e t N o . 32 : 32 p p . B o r o n d e f i c i e n c y i n f o r e s t p e a t l a n d i n N o r w a y . M e d d r . N o r s k . I n s t . S k o g f o r k . 3 5 : 213 - 2 3 6 . B . C . F o r e s t S e r v i c e B r i x , H . 1971 B r o c k l e y , R . P . 1981 1 9 6 9 . A n n u a l R e p o r t f o r t h e y e a r e n d i n g December 3 1 , 1 9 6 9 . M i n i s t r y o f F o r e s t s , V i c t o r i a , B . C . E f f e c t s o f n i t r o g e n f e r t i l i z a t i o n on 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 D o u g l a s - f i r . F o r . S c i . 1 7 : 407 - 4 1 4 . The e f f e c t s o f n u t r i e n t s and m o i s t u r e on s o i l n u t r i e n t a v a i l a b i l i t y , n u t r i e n t u p t a k e , t i s s u e n u t r i e n t c o n c e n t r a t i o n , and g r o w t h o f D o u g l a s - f i r s e e d l i n g s . M S c . T h e s i s , UBC , V a n c o u v e r , B . C . 170 p p . B u s z e w i c z , G . M , 1 9 7 0 . F o r e s t t r e e s e e d . I i i : R e p o r t on f o r e s t r e s e a r c h f o r y e a r e n d e d M a r c h , 1 9 7 0 . G . B . F o r . Comm. p p . 26 - 3 3 . C a n a d i a n D e p a r t m e n t o f A g r i c u l t u r e . 1 9 7 6 . The C a n a d i a n s y s t e m o f s o i l c l a s s i f i c a t i o n . C a n . D e p t . A g r . P u b l . 1 6 4 6 . -131-Carey, M.L. 1977. N u t r i t i o n a l d i s o r d e r s i n S i t k a spruce i n the R e p u b l i c of I r e l a n d . I r i s h F o r : AO - A6. Carey, M.L., E.P. F a r r e l l , and D.M. McAleese. 1981. M o b i l i z a t i o n of n u t r i e n t s i n a S i t k a s p ruce f o r e s t f l o o r . I . I n f l u e n c e of l i m e and f e r t i l i z e r s . F o r e s t E c o l . Manage. 3: 209 -227. Chapman, H.D. 1965. T o t a l exchangeable bases. Ln: C A . B l a c k ( e d . ) . Methods of s o i l a n a l y s i s , P a r t I I . S o i l S c i . Soc. Am., Madison, Wis., pp. 902 - 90A. C h a r l i s l e , A., and A.H.F. Brown. 1973. Nature c o n s e r v a n c y r e s e a r c h on the n u t r i t i o n of p i n e s on h i g h e l e v a t i o n p e a t . I_n: P e a t l a n d F o r e s t r y , P r o c , N a t u r a l Environment Research C o u n c i l . pp. 1A9 - 163. C o l e , D.W., and S.P. G e s s e l . 1963. Movement of elements through a f o r e s t s o i l as i n f l u e n c e d by t r e e removal and f e r t i l i z e r a d d i t i o n . I n : C.T. Youngberg ( e d . ) . F o r e s t - s o i l r e l a t i o n s h i p s i n N o r t h A m e r i c a . P r o c . 2nd Am. F o r . S o i l s Conf. pp. 95 - 10A. Comerford, N.B., N.I. Lamson, and A.L. L e a f . 1980. Measurement and i n t e r p r e t a t i o n of growth r e s p o n s e s of P i n u s r e s i n o s a t o K - f e r t i l i z a t i o n . F o r e s t E c o l . Manage. 2: 253 - 267. C o n n e l l , M.G.R., and S.C. W i l l e t t . 1975. Rates and t i m e s at which n e e d l e s are i n i t i a t d i n buds on d i f f e r i n g provenances of P i n u s  c o n t o r t a and P i c e a s i t c h e n s i s i n S c o t l a n d . Can. J . F o r . Res. 5: 367 -380. C o r d e s , L.D. 1972. An e c o l o g i c a l study of S i t k a spruce f o r e s t s on the west c o a s t of Vancouver I s l a n d . PhD. t h e s i s , Dept. Bot., UBC, Vancouver, B.C. A52 pp. Czapowskyj, M.M., L.O. S a f f o r d , and R.D. B r i g g s . 1980. F o l i a r n u t r i e n t s t a t u s of young red spruce and balsam f i r i n a f e r t i l i z e d s t a n d . USDA F o r . Serv. Res. Paper NE-467. 16 pp. - 1 3 2 -D a n g e r f i e l d , J . , and H. B r i x . 1 979. C o m p a r a t i v e e f f e c t s o f ammonium n i t r a t e and u r e a f e r t i l i z e r s on t r e e g r o w t h and s o i l p r o c e s s e s . I n : S.P. G e s s e l , R.M. K e n n d e d y , and W.A. A t k i n s o n ( e d s . ) . F o r e s t f e r t i l i z a t i o n c o n f e r e n c e . C o l l . F o r . C o n t r i b u t i o n No. 40: 133 - 139. D a v i d , M.B., S.C. S c h i n d l e r , M.J. M i t c h e l l , and J . E . S t r i c k . 1983. I m p o r t a n c e o f o r g a n i c and i n o r g a n i c s u l f u r t o m i n e r a l i z a t i o n p r o c e s s e s i n a f o r e s t s o i l . S o i l B i o l . B i o c h e m . 15: 671 - 677. D a v i e s , E.J.M. 1982. F o r e s t r y i n D u m f r i e s and G a l l o w a y . F o r e s t r y 55: 79 - 89. Da v i e s , R . I . , C.B C o u l s o n , and D.A. L e w i s . 1964. P o l y p h e n o l s i n p l a n t , humus, and s o i l . I V . F a c t o r s l e a d i n g t o i n c r e a s e s i n b i o s y n t h e s i s o f p o l y p h e n o l i n l e a v e s and t h e i r r e l a t i o n s h i p t o m u l l and mor f o r m a t i o n . J . S o i l S c i . 15: 310 - 318. Day, P.R. 1965. P a r t i c l e f r a c t i o n a t i o n and p a r t i c l e s i z e a n a l y s i s . Iri: C A . B l a c k ( e d . ) . M e t h o d s o f s o i l a n a l y s i s , P a r t I . S o i l S c i . S o c . Am., M a d i s o n , W i s . pp. 545 - 567. Day, W.R. 1957. S i t k a s p r u c e i n B r i t i s h C o l u m b i a . F o r . Comm. B u l l . No. 28. 110 pp. G.B, D e B e l l , D.S, E.H. M a l l o n e e , J . Y. L i n , and R.F. S t r a n d . 1975. F e r t i l i z a t i o n o f w e s t e r n h e m l o c k : A summary o f e x i s t i n g k n o w l e d g e . Crown Z e l l e r b a c h F o r e s t r y R e s . N o t e No. 5. 15 pp. d e k o c k , P.C. 1970. The m i n e r a l n u t r i t i o n o f p l a n t s s u p p l i e d w i t h n i t r a t e o r ammonium n i t r o g e n . In_: E.A. K i r k b y ( e d . ) . N i t r o g e n n u t r i t i o n o f t h e p l a n t ; U n i v e r s i t y o f L e e d s . pp. 39 - 44. D i c k s o n , D.A. 1973. . U t i l i z a t i o n o f n u t r i e n t s by t r e e s and v e g e t a t i o n on deep p e a t i n N o r t h e r n I r e l a n d . I_n: P e a t l a n d F o r e s t r y , P r o c , N a t u r a l E n v i r o n m e n t R e s e a r c h C o u n c i l . pp. 139 - 147. D i c k s o n , D.A., and P.S. S a v i l l . 1974. E a r l y g r o w t h o f P i c e a s i t c h e n s i s on p e a t i n N o r t h e r n I r e l a n d . F o r e s t r y 47: 57 - 88. - 1 3 3 -D i g h t o n , J . t and A . F . H a r r i s o n . 1 9 8 3 . P h o s p h o r u s n u t r i t i o n o f l o d g e p o l e p i n e and S i t k a s p r u c e a s i n d i c a t e d by a r o o t b i o a s s a y . F o r e s t r y 5 6 : 33 - 4 3 . E b e l l , L . F . 1 9 7 2 . C o n e - p r o d u c t i o n and s t e m - g r o w t h r e s p o n s e o f D o u g l a s - f i r t o r a t e and f r e q u e n c y o f n i t r o g e n f e r t i l i z a t i o n . C a n . J . F o r . R e s . 2 : 327 - 3 3 8 . E v e r a r d , J . E . 1 9 7 3 . F o l i a r a n a l y s i s — s a m p l i n g m e t h o d s , i n t e r p r e t a t i o n a n d a p p l i c a t i o n o f t h e r e s u l t s . Q . J . F o r . 4 7 : 51 - 6 6 . E v e r a r d , J . E . 1 9 7 4 . F e r t i l i z e r s i n t h e e s t a b l i s h m e n t o f c o n i f e r s i n W a l e s and S o u t h e r n E n g l a n d . G . B . F o r . Comm. B o o k l e t N o . 4 1 : 49 p p . F a r r , W . A . , A . S . H a r r i s , and S . N . I s r a e l s o n . 1 9 7 7 . E f f e c t s o f an a e r i a l a p p l i c a t i o n o f u r e a f e r t i l i z e r on y o u n g S i t k a s p r u c e and w e s t e r n h e m l o c k a t Thomas B a y , A l a s k a . USDA F o r . S e r v . R e s . P a p e r P N W - 2 1 9 . 15 p p . F a g e r s t r o m , T . , and U . L o h m . 1 9 7 7 . G r o w t h i n S c o t s p i n e ; M e c h a n i s m o f r e s p o n s e t o n i t r o g e n . O e c o l o g i a 2 6 : 205 - 2 1 5 . F e r d a , J . 1 9 7 5 . F o r e s t r y r e c l a m a t i o n o f e x t r a c t e d p e a t d e p o s i t s . S c i e n t i f i c M o n o g r a p h s . Res I n s t i t u t e f o r L a n d R e c l a m a t i o n and I m p r o v e m e n t . 192 p p . F i e d l e r , H . J . , W. N e b e , and J . L e r c h . 1 9 8 3 . F e r t i l i z a t i o n w i t h p h o s p h o r u s and n i t r o g e n i n y o u n g Norway s p r u c e s t a n d s . F e r t . R e s . 4 : 155 - 1 6 4 . G a r r e t t , P . W . , and R. Z a h m e r . 1 9 7 3 . F a s c i c l e d e n s i t y and n e e d l e g r o w t h r e s p o n s e s o f r e d p i n e t o w a t e r s u p p l y o v e r two s e a s o n s . E c o l o g y 5 4 : 1328 - 1 3 3 4 . G e s s e l , S . P . , E . C . S t e i n b r e n n e r , and R . E . M i l l e r . 1 9 7 9 . R e s p o n s e o f n o r t h w e s t f o r e s t s t o e l e m e n t s o t h e r t h a n n i t r o g e n . In.: S . P . G e s s e l , R . M . K e n n e d y , and W . A . A t k i n s o n ( e d s . ) . F o r e s t f e r t i l i z a t i o n c o n f e r e n c e . C o l l . F o r . R e s . , U n i v . W a s h . , I n s t i t . F o r . R e s . C o n t r i b u t i o n N o . 4 0 : 140 - 1 4 7 . -134-G i l l , R.S., and D.P. Lavender. 1983a. Urea F e r t i l i z a t i o n : E f f e c t s on p r i m a r y r o o t m o r t a l i t y and m y c o r r h i z a l development of young-growth w e s t e r n hemlock. F o r e s t S c i . 29: 751 - 760. G i l l , R.S., and D.P. Lavender. 1983b. Urea f e r t i l i z a t i o n and f o l i a r n u t r i e n t c o m p o s i t i o n of wes t e r n hemlock. F o r . E c o l . Manage. 68: 333 - 341. Gordon, J.C., and G.E. Gatherum. 1967. C o r r e l a t i o n s among f r e s h w e i g h t , dry w e i g h t , volume and t o t a l l e n g t h of n e e d l e s of S c o t s p i n e . F o r . S c i . 13: 426 - 427. S.E. A l l e n . 1956. Measurement of exchangeable and t o t a l c a t i o n c o n t e n t f o r H+, Na+, K+, Mg++, Ca++ and i r o n , i n h i g h l e v e l b l a n k e t p e a t . Oikos 7: 48 - 55. N i t r o g e n c y c l i n g i n c o n i f e r o u s ecosystems. Ln: F.E. C l a r k and T. R o s s w a l l ( e d s . ) . T e r r e s t r i a l n i t r o g e n c y c l e s . E c o l . B u l l . ( S tockholm) 33: 405 - 426. I n f l u e n c e of t r e e and s i t e f a c t o r s on we s t e r n r e d c e d a r ' s response t o r e l e a s e : A modeling a n a l y s i s . USDA F o r . S e r v . Res. Paper INT-296. 19 pp. H a i n e s , L.W., and S.G. S a n f e r f o r d . 1975. Biomass response to f e r t i l i z a t i o n i n the piedmont. I n : America's renewable r e s o u r c e p o t e n t i a l — 1975: the t u r n i n g p o i n t . P r o c . Soc. Am. F o r . pp. 425 - 440. Handley, W.R.C. 1963. M y c o r r h i z a l a s s o c i a t i o n and C a l l u n a h e a t h l a n d a f f o r e s t a t i o n . G.B. F o r . Comm. B u l l . No. 36. 70 pp. HMSO, London. He i l m a n , P. 1979. M i n e r a l s , c h e m i c a l p r o p e r t i e s , and f e r t i l i t y of f o r e s t s o i l s . In,: P.E. Heilman, H.W. Anderson and D.M. Baungar t n e r ( e d s . ) . F o r e s t s o i l s of the D o u g l a s - f i r r e g i o n . Wash. S t a t e U n i v . , Coop. E x t . S e r v . , P u l l m a n , Wash, pp. 121 - 136. Gore, A.J.P., and Gosz, J.R. 1981. Graham, R.T. 1982. -135-H e i l m an, P.E., and G. Ekuan. 1980. E f f e c t s of phosphorus on growth and m y c o r r h i z a l development of D o u g l a s - f i r i n greenhouse p o t s . S o i l S c i . Soc. Am. J . 44: 115 - 119. H e i n s d o r f , D. 1967. Untersuchungen e i b e r d i e Winkung m i n e r a l i s c h e r Diengung auf das Vachetum and den E r n a h r u n g s z u s t and von K i e f e r n k u l t u r e n auf Sandboden im mordostdeutschen t i e f l a n d . A r c h . F o r s t w . 16: 3 - 35. H o l l a n d , S.S. 1976. Landforms of B r i t i s h Columbia — a p h y s i o g r a p h i c o u t l i n e . B r i t i s h Columbia Dept. of Mines and P e t r o l e u m R e s o u r c e s , V i c t o r i a , B.C. 138 pp. I n g e s t a d , T. 1977. N i t r o g e n and p l a n t growth; Maximum e f f i c i e n c y of n i t r o g e n f e r t i l i z e r s . Ambio 6: 141 - 151. I n g e s t a d , T. 1979. N i t r o g e n s t r e s s i n b i r c h s e e d l i n g s . I I . N, P, K, Ca and Mg n u t r i t i o n . P h y s i o l . P l a n t . 45: 147 - 157. J a l a l , M.A.F., and D.J. Read. 1983a. The o r g a n i c a c i d c o m p o s i t i o n of C a l l u n a h e a t h l a n d s o i l w i t h s p e c i a l r e f e r e n c e t o phy t o - and f u n g i t o x i c i t y : I . I s o l a t i o n and i d e n t i f i c a t i o n of o r g a n i c a c i d s . P l a n t and S o i l 70: 257 - 272. J a l a l , M.A.F., and D.J. Read. 1983b. The o r g a n i c a c i d c o m p o s i t i o n of C a l l u n a h e a t h l a n d s o i l w i t h s p e c i a l r e f e r e n c e t o phy t o -and f u n g i t o x i c i t y : I I . Monthly q u a n t i t a t i v e d e t e r m i n a t i o n of the o r g a n i c a c i d c o n t e n t of C a l l u n a and spruce dominated s o i l s . P l a n t and S o i l 70: 273 - 288. Jo n e s , M.J., and J.W. P a r s o n s . 1970. The i n f l u e n c e of s o i l C/N r a t i o s on n i t r o g e n m i n e r a l i z a t i o n d u r i n g a n a e r o b i c i n c u b a t i o n . P l a n t and S o i l 32: 258 - 262. Keay, J . , A.G. T u r t o n , and N.A. Campbell. 1968. Some e f f e c t s of n i t r o g e n and phosphorus f e r t i l i z a t i o n on P i n u s p i n a s t e r i n wes t e r n A u s t r a l i a . F o r . S c i . 14: 408 - 417. - 1 3 6 -K e e n e y , D . R . 1 9 8 0 . P r e d i c t i o n o f s o i l n i t r o g e n a v a i l a b i l i t y i n f o r e s t e c o s y s t e m s : A l i t e r a t u r e r e v i e w . F o r . S c i . 2 6 : 159 - 1 7 1 . K i r k b y , E . A . , and A . D . H u g h e s . 1 9 7 0 . Some a s p e c t s o f ammonium and n i t r a t e n u t r i t i o n i n p l a n t m e t a b o l i s m . In.: E . A . K i r b y ( e d . ) . N i t r o g e n n u t r i t i o n o f t h e p l a n t ; U n i v e r s i t y o f L e e d s . p p . 69 - 7 7 . K l i n k a , K . , and F . C . N u s z d o r f e r . 1 9 7 9 . 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 s o u t h e r n V a n c o u v e r I s l a n d . P r o v i n c e o f B . C . , M i n i s t r y o f F o r e s t s , V i c t o r i a , B . C . 120 p p . K l i n k a , K . , M . C . F e l l e r , and L . E . L o w e . 1 9 7 9 . C h a r a c t e r i z a t i o n o f t h e most p r o d u c t i v e e c o s y s t e m s f o r g r o w t h o f P s e u d o t s u g a  m e n z i e s i i v a r . m e n z i e s i i i n S o u t h e r n B r i t i s h C o l u m b i a . M i n i s t r y o f F o r e s t s , V i c t o r i a , B . C . 49 p p . . K r a j i n a , V . J . , K. K l i n k a , and J . W o r r a l l . 1 9 8 2 . D i s t r i b u t i o n and e c o l o g i c a l c h a r a c t e r i s t i c s o f t r e e s and s h r u b s o f B r i t i s h C o l u m b i a . U B C , F a c u l t y o f F o r e s t r y , V a n c o u v e r , B . C . 31 p p . K r a u s s , H . H . 1 9 6 7 . K a l i e r n a h r ung und Wachstum von K i e f e r n k u l t u r e n u n d b e s t a n d e n a u f den v e r b r e i t e t s t e n s t a n d o r t e n im m o r d o s t d e u t s c h e n T i e f l a n d . I_n: F o r e s t f e r t i l i z a t i o n . P r o c . 5 t h C o l l o q . I n t . P o t a s h I n s t . p p . 206 - 2 1 6 . L a r g e n t , D . L . , N . S u g i h a r a , and C . W i s h n e r . 1 9 7 9 . O c c u r r e n c e o f m y c o r r h i z a e on e r i c a c e o u s and p y r o l a c e o u s p l a n t s i n n o r t h e r n C a l i f o r n i a . C a n . J . B o t . 5 8 : 2274 -2 2 7 9 . L e a f , A . L . 1 9 6 7 . P o t a s s i u m , m a g n e s i u m , and s u l f u r d e f i c i e n c i e s i n f o r e s t t r e e s . I n : F o r e s t f e r t i l i z a t i o n : t h e o r y and p r a c t i c e . T e n n . V a l . A u t h . , M u s c l e S h o a l s , A l a . p p . 88 - 1 2 2 . L e a f , A . L . 1 9 7 3 , P l a n t a n a l y s i s a s an a i d i n f e r t i l i z i n g f o r e s t s . In: L . M . W a l s h and J . D . B e a t o n ( e d s . ) . S o i l t e s t i n g and p l a n t a n a l y s i s ; S o i l S c i . S o c . A m . , M a d i s o n , W i s . p p . 426 - 4 5 4 . -137-L e w i s , T. 1982. L e y t o n , T. 1956. L e y t o n , T. 1952. L e y t o n , L. 1958. Macy, P. 1936. Madgwick, H.A.I. Ecosystems of the P o r t M c N e i l l b l o c k ( B l o c k 4) of Tree Farm L i c e n c e 25. I n t e r n a l r e p o r t . Western F o r e s t P r o d u c t s L t d . Unpub. The growth and m i n e r a l n u t r i t i o n of s p r u c e and p i n e i n h e a t h l a n d p l a n t a t i o n s . O x f o r d I m p e r i a l F o r . I n s t . Pap. No. 31. 109 pp. The e f f e c t of pH and form of n i t r o g e n on the growth of S i t k a s p r u c e s e e d l i n g s . F o r e s t r y 25: 32 - 40. The r e l a t i o n between growth and m i n e r a l c o m p o s i t i o n o f c o n i f e r s . Tn: K.V. Thimann ( e d . ) . The P h y s i o l o g y of F o r e s t T r e e s . Ronald P r e s s , New York, pp. 323 - 345. The q u a n t i t a t i v e m i n e r a l r e q u i r e m e n t s of p l a n t s . P l a n t P h y s i o l . 11: 749 - 764. 1964. The c h e m i c a l c o m p o s i t i o n of the f o l i a g e as an i n d e x of n u t r i t i o n a l s t a t u s i n r e d p i n e . P l a n t and S o i l 21: 70 - 80. Mahendrappa, M.K., and P.O. S a l o n i u s . 1982. N u t r i e n t dynamics and growth response i n a f e r t i l i z e d b l a c k spruce s t a n d . S o i l S c i . Soc. Am. J . 46: 127 - 133. M a k i , T.E. 1960. Some e f f e c t s of f e r t i l i z e r s on l o b l o l l y p i n e . P r o c . 7 t h I n t e r n . Congress of S o i l S c i e n c e , Madison, Wis. pp. 363 - 375. Maynard, D.G., J.W.B. S t e w a r t , and J.R. B e t t a n y . 1982. D i a g n o s i s of s u l f u r d e f i c i e n c y i n p l a n t s and s o i l s . Ijn: P r o c . 19th Ann. A l b e r t a S o i l S c i . Workshop. pp. 207 -228. M c i n t o s h , R. 1978. Response of S i t k a s pruce t o r e m e d i a l f e r t i l i z a t i o n i n G a l l o w a y . S c o t t . F o r . 32: 271 - 282. M c i n t o s h , R. 1981. F e r t i l i z e r t r e a t m e n t of S i t k a spruce i n the e s t a b l i s h m e n t phase i n upland B r i t a i n . S c o t t . F o r . 35: 3 - 13. -138-M c l n t o s h , R. 1982. M c i n t o s h , R. 1983. E f f e c t s of d i f f e r e n t forms and r a t e s of n i t r o g e n f e r t i l i z e r on the growth of l o d g e p o l e p i n e . F o r e s t r y 55: 61 - 68. N i t r o g e n d e f i c i e n c y i n e s t a b l i s h m e n t phase S i t k a s pruce i n u p l a n d B r i t a i n . S c o t t . F o r . 37: 185 - 193. McNabb, R.F.R. 1961 M y c o r r h i z a i n the New Zea l a n d E r i c a l e s . A u s t . J . B o t . 9: 57 - 61. M e l i n , J . , H. Nommik, U. Lohm, and J . F l o w e r - E l l i s . 1983. F e r t i l i z e r n i t r o g e n budget i n a S c o t s p i n e ecosystem a t t a i n e d by u s i n g r o o t - i s o l a t e d p l o t s and 15N t r a c e r t e c h n i q u e . P l a n t and S o i l 74: 249 -163. M e l l o r , C.E., and E.B. Tregunna. 1972. The r e l a t i o n s h i p between l e a f a r e a and l e a f dry weight of t h r e e c o n i f e r s p e c i e s grown on t h r e e s o u r c e s of n i t r o g e n . Can. J . F o r . Res. 2: 377 - 379. Mengel, K., and E.A. K i r k b y . 1979. P r i n c i p l e s of p l a n t n u t r i t i o n . I n t e r n a t i o n a l P o t a s h I n s t i t u t e . 593 pp. M e u r i s s e , R.T. 1976. Some c h e m i c a l and o t h e r p r o p e r t i e s of wes t e r n hemlock s o i l s i n O r e g o n — t h e i r r e l a t i o n s h i p t o p r o d u c t i v i t y . I n : W.A. A t k i n s o n and R.J. Z a s o s k i ( e d s . ) . Western hemlock management. C o l l . F o r . Res., U n i v . Wash., I n s t i t . F o r . P r o d . C o n t r i b u t i o n No. 34: 49 - 55. M i c h a e l , G., P. M a r t i n , and I . Owassia. 1970. The uptake of ammonium and n i t r a t e from l a b e l l e d ammonium n i t r a t e i n r e l a t i o n t o the c a r b o h y d r a t e s u p p l y of r o o t s . I n : A. K i r b y ( e d . ) . N i t r o g e n n u t r i t i o n of the p l a n t ; U n i v e r s i t y of Leeds. pp. 22 - 29. M i l l e r , H.G. 1981. F o r e s t f e r t i l i z a t i o n : some g u i d i n g c o n c e p t s . F o r e s t r y 54: 157 - 167. M i l l e r , H.G5., and J.D. M i l l e r . 1976. E f f e c t of n i t r o g e n s u p p l y on net pr i m a r y p r o d u c t i o n i n C o r s i c a n p i n e . J . A p p l . E c o l . 13: 233 - 248. -139-M i l l e r , H.G., J.D. M i l l e r , and J.M. Cooper. 1981. Optimum f o l i a r n i t r o g e n c o n c e n t r a t i o n i n p i n e and i t s change w i t h s t a n d age. Can. J . F o r . Res. 11: 563 - 572. M i l l e r , R.E., and R.F. T a r r a n t . 1983. Long-term growth response of D o u g l a s - f i r t o ammonium n i t r a t e f e r t i l i z e r . F o r e s t S c i . 29: 127 - 137. Minderman, G. 1968. A d d i t i o n , d e c o m p o s i t i o n and a c c u m u l a t i o n of o r g a n i c m a t t e r i n f o r e s t s . J . Eco. 56: 355 - 362. M i n o r e , D. 1970. S e e d l i n g growth of e i g h t n o r t h w e s t e r n t r e e s p e c i e s over t h r e e water t a b l e s . USDA F o r . S e r v . Res. Note PNW-115. 8 pp. M o l i n a , R., and J.M. Trappe. 1982. Lack of m y c o r r h i z a l s p e c i f i c i t y by the E r i c a c e o u s h o s t s A r b u t u s m e n z i e s i i and A r c t o s t a p h y l o s  u v a - u r s i . New P h y t o l . 90: 495 - 509. M o r r i s o n , I.K. 1974. M i n e r a l n u t r i t i o n of c o n i f e r s w i t h s p e c i a l r e f e r e n c e t o n u t r i e n t s t a t u s i n t e r p r e t a t i o n : A r e v i e w of L i t e r a t u r e . Can. F o r . Se r v . Pub. No. 1343. Morrow, L. 1979. An approach t o p r e d i c t n u t r i e n t s t a t u s and growth response of f e r t i l i z e d J a c k p i n e by d i a g n o s i s . MSc. T h e s i s , Lakehead U n i v e r s i t y , Ont. 71 pp. Morrow, L.D., and V.R. Timmer. 1981. I n t r a s e a s o n a l growth and n u t r i e n t c o m p o s i t i o n of J a c k p i n e n e e d l e s f o l l o w i n g f e r t i l i z a t i o n . Can. J . F o r . Res. 11: 696 - 702. Murphy, L.S. 1980. P o t a s s i u m i n t e r a c t i o n s w i t h o t h e r e l e m e n t s . I n : P o t a s s i u m f o r a g r i c u l t u r e . P o t a s h and Phosphate I n s t i t u t e , A t l a n t a , GA. pp. 182 - 203. Nommik, H., and G. M o l l e r . 1981. N i t r o g e n r e c o v e r y i n s o i l and n e e d l e biomass a f t e r f e r t i l i z a t i o n of a S c o t s p i n e s t a n d , and growth r e s p o n s e s o b t a i n e d . S t u d i a F o r . S u e c i c a No. 159: 37 pp. -140-Nommik, H., and B. P o p o v i c . 1971. Recovery and v e r t i c a l d i s t r i b u t i o n of 15N l a b e l l e d f e r t i l i z e r n i t r o g e n i n f o r e s t s o i l s . S t u d i a F o r . S u e c i c a No. 92: 1 - 19. O l s e n , S.R. 1972. M i c r o n u t r i e n t i n t e r a c t i o n s . I n : J . J . M o r t v e d t , P.M. G i o r d a n o , and W'.L. L i n d s a y ( e d s . ) . M i c r o n u t r i e n t s i n a g r i c u l t u r e . S o i l S c i . Soc. Am. I n c . , Madison, Wis. pp. 243 - 264. O l s e n , S.R., and L.E. Sommers. 1982. Phosphorus. I n : C.A. B l a c k ( e d . ) . Methods of s o i l a n a l y s i s ; P a r t I I . 2nd ed. S o i l S c i . Soc. Am., Madison, Wis. pp. 403 - 428. 01 son, J . , W. A t k i n s o n , and M. R i n e h a r t . 1979* Response of wes t e r n hemlock t o n i t r o g e n f e r t i l i z a t i o n and t h i n n i n g i n the P a c i f i c N o r t h w e s t . JEn: F o r e s t F e r t i l i z a t i o n C o n f e r e n c e . U n i v . Wash. C o l l . F o r . Res. I n s t . F o r . Res. C o n t r i b . No. 40. pp. 69 - 77. Oserkowsky, J . 1933. Q u a n t i t a t i v e r e l a t i o n between c h l o r o p h y l l and i r o n i n green and c h l o r o t i c pear l e a v e s . P l a n t P h y s i o l . 8: 449 - 468. O v e r r e i n , L.N. 1969. L y s i m e t e r s t u d i e s on t r a c e r n i t r o g e n i n f o r e s t s o i l s : I I . Comparative l o s s e s of n i t r o g e n through l e a c h i n g and v o l a t i l i z a t i o n a f t e r the a d d i t i o n of u r e a - ammmonium- and n i t r a t e - 1 5 N . S o i l S c i . 107: 149 - 159. P a r k e , J . L . , R.G. Linderman, and J.M. Trappe. 1983. E f f e c t s of f o r e s t l i t t e r on m y c o r r h i z a development and growth o f D o u g l a s - f i r and w e s t e r n r e d cedar s e e d l i n g s . Can. J . F o r . Res. 13: 666 - 671. P e a r s o n , V., and D.J. Read. 1973. The b i o l o g y of m y c o r r h i z a i n the E r i c a c e a e . I . The i s o l a t i o n of the endophyte and s y n t h e s i s of m y c o r r h i z a s i n a s e p t i c c u l t u r e . New P h y t o l . 72: 371 - 379. P e t e r s o n , E.B. 1965. I n h i b i t i o n of b l a c k s pruce primary r o o t s by a w a t e r - s o l u b l e substance i n K a l m i a a n g u s t i f o l i a . F o r . S c i . 11: 473 - 479. -141-P o l l a r d , D.F.W., and K.T. Logan. 1977. The e f f e c t s of l i g h t i n t e n s i t y , p h o t o p e r i o d , s o i l m o i s t u r e p o t e n t i a l , and temperature on bud morphogenesis i n P i c e a s p e c i e s . Can. J . F o r . Res. 7: 415 - 421. M i n e r a l i z a b l e s o i l n i t r o g e n as an i n d e x of n i t r o g e n a v a i l a b i l i t y t o f o r e s t t r e e s . S o i l S c i . Soc. Am. J . 44: 1324 - 1330. F o r e s t f e r t i l i z a t i o n r e s e a r c h i n C a l i f o r n i a . I n : F o r e s t s i t e and c o n t i n u o u s p r o d u c t i v i t y . IUFR0, S e a t t l e , Wash. pp. 388 - 397. F e r t i l i z a t i o n program BLM Salem D i s t r i c t . Ln: N i t r o g e n assessment workshop, 1982; R.F.N.R.P. Report No. 2; C o l l . of F o r . Res. AR-10, U n i v . Wash. pp. 46 - 50. P r i t c h e t t , W.L. 1979. P r o p e r t i e s and management of f o r e s t s o i l s . John W i l e y and Sons, New York. P r i t c h e t t , W.L., and N.B. Comerford. 1982. Long-term response t o phosphorus f e r t i l i z a t i o n on s e l e c t e d s o u t h e a s t e r n c o a s t a l p l a i n s o i l s . S o i l S c i . Soc. Am. J . 46: 640 - 644. Q u e s n e l , H.J. 1981. F o r e s t f l o o r s near P o r t Hardy, B.C. MSc. T h e s i s , UBC, Dept. of S o i l S c i . , Vancouver, B.C. 152 pp. Radwan, M.A., and D.S. D e B e l l . 1980. E f f e c t s of d i f f e r e n t s o u r c e s of f e r t i l i z e r n i t r o g e n on growth and n u t r i t i o n of western hemlock s e e d l i n g s . USDA F o r . S e r v . , Res. Paper PNW-267. 15 pp. Radwan, M.A., and J.S. Shumway. 1983. S o i l n i t r o g e n , s u l f u r and phosphorus i n r e l a t i o n t o growth response of wester n hemlock t o n i t r o g e n f e r t i l i z a t i o n . F o r . S c i . 29: 469 - 477. Powers, R.F. 1980. Powers, R.F. 1983. Powers, W.E. 1984. R i c e , F.L. 1979. A l l e o p h a t h y — a n update. B o t . Rev. 45: 15 - 109. -142-R i c h a r d s , B.N., and D.I. Bevege. 1972. P r i n c i p l e s and p r a c t i c e of f o l i a r a n a l y s i s as a b a s i s f o r c r o p - l o g g i n g i n p i n e p l a n t a t i o n s . I . B a s i c c o n s i d e r a t i o n s . P l a n t and S o i l 36: 109 - 119. R o b i n s o n , R.K. 1972. The p r o d u c t i o n by r o o t s of C a l l u n a v u l g a r i s of a f a c t o r i n h i b i t o r y t o the growth of some m y c o r r h i z a l f u n g i . J . Eco. 60: 219 - 224. Roche, L., and D.P. F o w l e r . 1975. G e n e t i c s of S i t k a s p r u c e . USDA F o r . S e r v . Res. Paper W0-26. 15 pp. Ross, S.M., and D.C. M a l colm. 1982. E f f e c t s of i n t e n s i v e f o r e s t r y p l o u g h i n g p r a c t i c e s on an u pland heath s o i l i n South E a s t S c o t l a n d . F o r e s t r y 55: 155 - 171. R o v i r a , A.D., G.D. Bowen, and R.C. F o s t e r . 1983. The s i g n i f i c a n c e of r h i z o s p h e r e m i c r o f l o r a and m y c o r r h i z a s i n p l a n t n u t r i t i o n . I n : A. L a u c h l i and R.L. B i e l e s k i ( e d s . ) . I n o r g a n i c p l a n t n u t r i t i o n . E n c y c l o p e d i a of P l a n t P h y s i o l o g y , New S e r i e s Volume 15A, S p r i n g e r - V e r l a g , B e r l i n . pp. 61 - 93. S a l o n i u s , P.O., and M.K. Mahendrappa. 1983. A comparison of growth promotion by c o n t r o l l e d r e l e a s e ureas and c o n v e n t i o n a l n i t r o g e n f e r t i l i z e r s u s i n g two m e n s u r a t i o n a l methods. _In: F o r e s t S i t e and C o n t i n u o u s P r o d u c t i v i t y . IUFR0, S e a t t l e , Wash. pp. 398 - 403. Sheppard, S.C., and J.G. Racz. 1980. Phosphorus n u t r i t i o n of c r o p s as a f f e c t e d by t emperature and water s u p p l y . I i i : Western Canada Phosphate Symposium P r o c e e d i n g s . pp. 159 - 199. S h i c k l u n a , J.C., and R.E. L u c a s , and J.F. D a v i s . 1972. The movements of potassium i n o r g a n i c s o i l s . JEn: The use of p e a t l a n d s f o r a g r i c u l t u r e , h o r t i c u l t u r e and f o r e s t r y . P r o c . 4 t h I n t e r n a t i o n a l Peat Congress, O t a n i e m i , F i n l a n d . pp. 131 - 140. -143-Shumway, J.S., and W.A. A t k i n s o n . 1977. Measuring and p r e d i c t i n g growth response i n un t h i n n e d s t a n d s of D o u g l a s - f i r by p a i r e d t r e e a n a l y s i s and s o i l t e s t i n g . S t a t e of Wash., Dept. Nat. Res., DNR Note No. 15. 10 pp. Shumway, J.S., and W.A. A t k i n s o n . 1978. P r e d i c t i n g n i t r o g e n f e r t i l i z e r r e s p onse i n un t h i n n e d s t a n d s of D o u g l a s - f i r . Commu. i n S o i l S c i . and P l a n t A n a l y . 9: 529 - 539. S i d l e , R.C., and C.G. Shaw. 1983. E v a l u a t i o n of p l a n t i n g s i t e s common t o a s o u t h e a s t A l a s k a c l e a r - c u t . I . N u t r i e n t s t a t u s . Can. J . F o r . Res. 13: 1 - 8 . Smi t h , P.F. 1962. M i n e r a l a n a l y s i s of p l a n t t i s s u e . Ann. Rev. P l a n t . P h y s i o l . 13: 81 - 108. S i l f v e r b e r g , K. 1980. [Summary: M i c r o n u t r i t i o n a l growth d i s o r d e r i n Norway s p r u c e . ] F o l i a F o r . 432: 1 - 13. Specht, R.L. 1979. He a t h l a n d s and r e l a t e d s h r u b l a n d s of the w o r l d . I i i : Ecosystems of the w o r l d 9A: H e a t h l a n d s and r e l a t e d s h r u b l a n d s ; D e s c r i p t i v e S t u d i e s . E l s e v i e r S c i e n t i f i c P u b l i s h i n g Co., New York, pp. 1 - 18. S t e e n b j e r g , F. 1952. Y i e l d c u r v e s and c h e m i c a l p l a n t a n a l y s i s . P l a n t and S o i l 3: 97 - 109. Mic r o e l e m e n t n u t r i t i o n of f o r e s t t r e e s : A r e v i e w . I_n: F o r e s t f e r t i l i z a t i o n : t h e o r y and p r a c t i c e . Tenn. V a l . Auth., Muscle S h o a l s , A l a . pp. 132 - 175. An attempt t o a s s e s s the optimum n i t r o g e n l e v e l i n Norway sp r u c e under f i e l d c o n d i t i o n s . S t u d i a F o r . S u e c i c a No. 61. 67 pp. Exper i m e n t s t o a n a l y s e the be h a v i o u r of young spruce f o r e s t a t d i f f e r e n t n u t r i e n t l e v e l s . L a: F i r s t I n t e r n a t i o n a l Congress of E c o l o g y : P r o c . The Hague, the N e t h e r l a n d s . pp. 266 - 272. Stone, E.L. 1967. Tamm, C O . 1968. Tamm, C O . 1974. -144-Tamm, C O . 1982. N i t r o g e n c y c l i n g i n u n d i s t u r b e d and m a n i p u l a t e d b o r e a l f o r e s t . I n : W.D.P. Steward and T. R o s s w a l l ( e d s . ) . The n i t r o g e n c y c l e . P h i l . T r a n s . R. Soc. Land. B296: 419 -425. T a y l o r , R.F. 1935. A v a i l a b l e n i t r o g e n as a f a c t o r i n f l u e n c i n g the o c c u r r e n c e of S i t k a s p ruce and we s t e r n hemlock s e e d l i n g s i n f o r e s t s of South E a s t A l a s k a . E c o l o g y 16: 580 - 593. T i a r k s , A.E. 1983. E f f e c t s of s i t e p r e p a r a t i o n and f e r t i l i z a t i o n on s l a s h p i n e growing on good s i t e s . Jin: E.P. Jones ( e d . ) . P r o c . of the second b i e n n i a l s o u t h e r n s i l v i c u l t u r a l r e s e a r c h c o n f e r e n c e . USDA F o r . S e r v . Gen. Tech. Rep. SE-24. pp. 34 - 39. Timmer, V.R., and E.L. Stone. 1978. Comparative f o l i a r a n a l y s i s of young balsam f i r f e r t i l i z e d w i t h N,P,K and l i m e . S o i l S c i . Soc. Am. J . 42: 125 - 130. T i n k e r , P.B. 1979. The r o l e of r h i z o s p h e r e m i c r o o r g a n i s m s . I n : G. Sample and F.E. Khasawheh ( e d s . ) . The r o l e of phosphorus i n a g r i c u l t u r e . Tenn. V a l . Auth., Muscle S h o a l s , A l a . pp. 617 - 654. Toleman, R.D.L. 1973. A peat c l a s s i f i c a t i o n f o r f o r e s t use i n G r e a t B r i t a i n . _In: C l a s s i f i c a t i o n of peat and p e a t l a n d s . P r o c , I n t e r . Peat S o c , G l a s g l o w , S c o t . pp. 84 -97. T u r n e r , J . , and P.R. O l s o n . 1976. N i t r o g e n r e l a t i o n s i n a D o u g l a s - f i r p l a n t a t i o n . Ann. B o t . 40: 1185 - 1193. T u r n e r , J . , M.C. Lambert, and S.P. G e s s e l . 1977. Use of f o l i a g e s u l p h a t e c o n c e n t r a t i o n s t o p r e d i c t response t o urea a p p l i c a t i o n by D o u g l a s - f i r . Can. J . F o r . Res. 7: 476 - 486. T u r n e r , J . , S.F. D i c e , D.E. C o l e , and S.P. G e s s e l . 1978. V a r i a t i o n of n u t r i e n t s i n f o r e s t t r e e f o l i a g e — A r e v i e w . U n i v . Wash. C o l l . F o r . Res. I n s t . F o r . P r o d . C o n t r i b . No. 35. 32 pp. -145-van den D r i e s s c h e , R. 1971. Response of c o n i f e r s e e d l i n g s t o n i t r a t e and ammonium s o u r c e s of n i t r o g e n . P l a n t and S o i l 34: 421 -439. van den D r i e s s c h e , R. 1973. F o l i a r n u t r i e n t c o n c e n t r a t i o n d i f f e r e n c e s between provenances of D o u g l a s - f i r and t h e i r s i g n i f i c a n c e t o f o l i a r a n a l y s i s i n t e r p r e t a t i o n s . Can. J . F o r . Res. 3: 323 - 328. van den D r i e s s c h e , R. 1974. P r e d i c t i o n of m i n e r a l n u t r i e n t s t a t u s of t r e e s by f o l i a r a n a l y s i s . B o t . Rev. 40: 347 - 394. van den D r i e s s c h e , R., and J . D a n g e r f i e l d . 1975. Response of D o u g l a s - f i r s e e d l i n g s t o n i t r a t e and ammonium n i t r o g e n s o u r c e s under v a r i o u s e n v i r o n m e n t a l c o n d i t i o n s . P l a n t and S o i l 42: 685 - 702. V e i j a l a i n e n , H, V e i j a l a i n e n , H, 1977. Use of ne e d l e a n a l y s i s f o r d i a g n o s i n g m i c r o - n u t r i e n t d e f i c i e n c i e s of S c o t s p i n e on d r a i n e d p e a t l a n d s . Comm. I n s t . F o r . Fenn. 92 ( 4 ) : 1 -32. 1981. [Summary: Long-term r e s p o n s e s of S c o t s p i n e t o m i c r o - n u t r i e n t f e r t i l i z a t i o n on a c i d peat s o i l . ] F o l i a F o r . 477: 1 - 1 5 . Vimmerstedt, J.P., and C A . Osmond. 1968. Response^ of y e l l o w - p o p l a r t o f e r t i l i z a t i o n . I n : C.T. Youngberg and C.B. Davey ( e d s . ) . Tree growth and f o r e s t s o i l s . P r o c . 3rd N o r t h Am. F o r . S o i l Conf. pp. 127 - 153. Vogt, D.J., and R.L. Edmonds. 1984. Ammonium and n i t r a t e c o n c e n t r a t i o n s i n s o i l s and f o r e s t f l o o r s of D o u g l a s - f i r s t a n d s i n western Washington. .In: N i t r o g e n assessment workshop, 1982; R.F.M.P. Report No. 2, C o l l . of F o r , Res., U n i v . Wash. pp. 14 - 34. Waring, S.A., and J . Bremner. 1964. Ammonium p r o d u c t i o n i n s o i l under w a t e r l o g g e d c o n d i t i o n s as an in d e x of n i t r o g e n a v a i l a b i l i t y . Nature 201: 951 - 952. -146-Waring, R.H., and C.T. Youngberg. 1972. E v a l u a t i n g f o r e s t s i t e s f o r p o t e n t i a l growth response of t r e e s t o f e r t i l i z e r . Northwest S c i . 46: 67 -75.. Webster, S.R., D.S. D e B e l l , K.N. W i l e y , and W.A. A t k i n s o n . 1976. F e r t i l i z a t i o n of we s t e r n hemlock. I_n: W.A. A t k i n s o n and R.Z. Z a s o s k i ( e d s . ) . w e s t e r n hemlock Management. C o l l . F o r . Res., U n i v . Wash., I n s t . F o r . P r o d . , C o n t r i b u t i o n No. 34. pp. 247 - 252. Weetman, G.F., and D. A l g a r . 1974. J a c k p i n e n i t r o g e n f e r t i l i z a t i o n and n u t r i t i o n s t u d i e s : Three year r e s u l t s . Can. J . F o r . Res. 4: 381 - 398. Weetman, G.F., and R. F o u r n i e r . 1983. G r a p h i c a l d i a g n o s i s of l o d g e p o l e p i n e response t o f e r t i l i z a t i o n . S o i l S c i . Soc. Am. J . 46: 1280 - 1289. Welch, L.F., and A.D. S c o t t . 1961. A v a i l a b i l i t y of non-exchangeable s o i l p o t a s s i u m t o p l a n t s as a f f e c t e d by added K+ and NH4+. S o i l S c i . Soc. Am. P r o c . 25: 102 - 104. W i l l i a m s , B.L., J.M. Cooper, and D.G. P y a t t . 1978. E f f e c t s of a f f o r e s t a t i o n w i t h P i n u s c o n t o r t a on n u t r i e n t c o n t e n t , a c i d i t y and exchangeable c a t i o n s i n peat. F o r e s t r y 51: 29 - 35. W i l l i a m s , B.L., J.M. Cooper, and D.G. P y a t t . 1979. Some e f f e c t s of a f f o r e s t a t i o n w i t h l o d g e p o l e p i n e on r a t e s of n i t r o g e n m i n e r a l i z a t i o n i n p e a t . F o r e s t r y 52: 151 - 162. Woodhouse, H.W., and K. Hardwick. 1966. The growth of tomato s e e d l i n g s i n r e l a t i o n t o the form of N s u p p l y . New P h y t o l . 65: 518 - 525. Youngberg, C.T. 1978. N i t r o g e n m i n e r a l i z a t i o n and uptake from D o u g l a s - f i r f o r e s t f l o o r s . S o i l S c i . Soc. Am. J . 42: 489 - 502. -147-APPENDIX I The a n a l y s i s o f v a r i a n c e and S t u d e n t - N e w m a n - K e u l s ' m u l t i p l e r a n g e t e s t o f i n d i v i d u a l s t a n d s . - 1 4 8 -STAND - 1 TREATMENT EFFECTS SOURCE OF VARIATION: N P K NP NK PK NPK DEGREES OF FREEDOM: 3 1 1 3 3 . 1 3 N e e d l e W e i g h t 1983 L e a d e r G r o w t h ** ** ** * * * N e e d l e C o n c e n t r a t i o n N ** * p ** ** * ** K ** ** ** Ca Mg * * ** N u t r i e n t C o n t e n t N ** ** P ** ** * * K ** * * Ca Mg ** * ** ** * S i g n i f i c a n t a t 0.05 l e v e l . ** S i g n i f i c a n t a t 0.01 l e v e l . -149-STAND - 2 TREATMENT EFFECTS SOURCE OF VARIATION: N P K NP NK PK NPK DEGREES OF FREEDOM: 3 1 1 3 3 1 3 N e e d l e W e i g h t 1983 L e a d e r G r o w t h P N u t r i e n t C o n t e n t N P ** ** * ** ** ** N e e d l e C o n c e n t r a t i o n N * * * * ** * £ * * * * * * * * Ca Mg ** ** ** ** ** ** £ ** ** Ca ** ** Mg ** ** * S i g n i f i c a n t a t 0.05 l e v e l . ** S i g n i f i c a n t a t 0.01 l e v e l . - 1 5 0 -STAND - 3 TREATMENT EFFECTS SOURCE OF VARIATION: N P K NP NK PK NPK DEGREES OF FREEDOM: 3 1 1 3 3 1 3 N e e d l e W e i g h t 1983 L e a d e r G r o w t h ** ** ** ** ** ** N e e d l e C o n c e n t r a t i o n N ** ** * P . K ** ** ** * * ** Ca Mg ** ** ** N u t r i e n t C o n t e n t N ** ** ** P ** ** * K ** ** ** * ** * Ca ** ** * ** Mg ** * * * S i g n i f i c a n t a t 0.05 l e v e l . ** S i g n i f i c a n t a t 0.01 l e v e l . - 1 5 1 -STAND - 4 TREATMENT EFFECTS SOURCE OF VARIATION: N P K NP NK PK NPK DEGREES OF FREEDOM: 3 1 1 3 3 1 3 N e e d l e W e i g h t 1983 L e a d e r G r o w t h ** ** ** ** ** * N e e d l e C o n c e n t r a t i o n N ** ** P ** ** K ** * ** ** ** Ca Mg * N u t r i e n t C o n t e n t N ** ** P ** ** * K ** ** * * ** ** Ca Mg ** ** ** ** * * S i g n i f i c a n t a t 0.05 l e v e l . ** S i g n i f i c a n t a t 0.01 l e v e l . - 1 5 2 -STAND - 5 TREATMENT EFFECTS SOURCE OF VARIATION: N P K NP NK PK NPK DEGREES OF FREEDOM: 3 1 1 3 3 1 3 N e e d l e W e i g h t 1983 L e a d e r G r o w t h ** ** ** ** ** ** * ** N e e d l e C o n c e n t r a t i o n N ** ** P * ** K ** ** ** ** ** Ca ** ** ** Mg N u t r i e n t C o n t e n t N ** ** * P ** ** * K ** ** ** * ** Ca ** ** ** ** ** Mg ** ** * S i g n i f i c a n t a t 0.05 l e v e l . ** S i g n i f i c a n t a t 0.01 l e v e l . I. 1983 L e a d e r Growth ( c m ) . NO NOPK NOP NOK N3 Nl N2 N2K N3K N2P NIK NPKT N2PK N3PK NIP N3P N2PK 10.5 10.6 11.2 12.1 1A, 15, 15, 15, 16, 18.0 18.7 19.6 21.1 21.9 22.6 23.0 23.2 NOP NOK N2K N3K N3 N2 NIK NOPK NO N l N1PK N2PK N3P N3PK N2P NIP NPKT 6, 8, 9, 9, 9, 9. 9.6 9.7 9.8 11.2 12.8 13.8 13.8 14.1 14.7 18.2 18.3 NOPK NOP N l NOK N3 N2 N3K N2K NIK N l N3PK N2P NIP NPKT N1PK N3P N2PK 8.1 9.3 9.6 10.5 11 .A 11.7 11.8 12, 12, 1A.0 16.1 16.1 16.2 18.6 18.8 19.A 19.6 NOK NOP NOPK NO Nl N3K N2K NIK N3 N3PK N2 N3P N1PK N2PK N2P NPKT NIP 7.A 9.7 10.7 11.6 12.2 12, 12, 13, 15, 16.5 16.8 19.2 19.6 20.1 20.3 21.1 21.2 NO NOP NOPK NOK N2K NIK N3K Nl N2 N3 N3P N1PK N2PK N2P N3PK NIP NPKT 8.A 8.7 8.9 11.2 11 11 12.1 12.2 12.A 13.5 1A.9 15.1 15.3 16.7 18.8 20.0 20.6 T r e a t m e n t s c o n n e c t e d by t h e same l i n e a r e n o t s i g n i f i c a n t l y d i f f e r e n t a t p=.01. I -154-II. Needle Weight (g/100 needles), STAND - 1 STAND - 2 STAND STAND - 4 STAND NOP .414 ( .051) NO .421 ( .092) N3 .456 ( .051) NOPK .464 ( .072) NOK .478 ( .062) N2K .485 ( .120) N2 .498 ( .130) NIK . 507 ( . 104) N3K .521 ( .154) Nl .540 ( .091) N2P .602 ( .036) N3P .616 ( .112) N3PK .616 ( .059) N1PK .657 ( .146) N2PK .681 ( .213) NPKT .716 ( .170) NIP .775 ( . 198) N3K .441 (.085) N2 .448 (.090) N3 .450 (.088) NO .474 (.025) NOP .476 (.096) NOK .479 (.085) NOPK .485 (.067) NIK .498 (•140) N2K .515 (•104) Nl .531 (.074) N3PK .588 (.065) N3P .591 (.141) N2PK .629 (.091) N2P .648 (.116) N1PK .678 (.133) NIP .691 ( . 162) NPKT .786 (.172) NOPK .465 (.107) N3K .485 (.089) NOP .487 (.115) N2 .504 ( .105) NO .508 (.025) NIK .518 (.088) NOK .528 (.079) Nl .539 (.121) N3 .556 (.113) N2K .565 (.096) N2PK .650 ( .071) NIP .653 ( .077) N2P .654 (.112) N3PK .668 ( .075) N3P .706 (.116) N1PK .728 (.114) NPKT .877 ( .169) NOK .347 (.058) NOP .362 (.141) Nl .397 (.020) NOPK .414 (.056) NO .408 (.092) NO .439 (.061) NOPK .413 (.109) N3K .439 (.094) NOP .415 (.063) N2 .481 (.076) N2 .466 (. 102) N2K .488 (.074) N3K .472 (• 109) NIK .515 (.082) NIK .494 (.088) NOK .517 (.088) N3PK .507 (.139) N3 .529 (.107) N2K .516 ( .122) N3P .529 (.065) N3 .516 (.120) Nl .543 (.112) N2P .557 (.056) N2PK .605 (.085) N3P .571 ( .116) N2P .606 ( .072) N2PK .572 ( .114) NIP .611 (.097) NIP .626 ( .166) N1PK .617 (.093) N1PK .637 ( . 136) NPKT .663 (.108) NPKT .675 ( .139) N3PK .698 (.113) Treatments connected by the same line are not sign i f i c a n t l y different at p=.01. Values in parenthesis + 1 SD. -155- i III. Nitrogen concentration {% oven-dry weight), STAND - 1 STAND - 2 STAND STAND - 4 STAND - 5 NOK NO NOP NOPK Nl NIP NIK NPKT N1PK N2K N2PK N3K N2 N3P N3PK N2P N3 0.78 0.78 0.81 0.97 66 68 89 03 25 41 3.53 3.55 66 69 70 96 3.97 . 101) .075) . 100) . 132) . 537) . 477) .506) .369) .737) .623) .580) .544) .902) .498) .456) .410) .336) NO NOK NOPK NOP Nl NIK NIP NPKT N2K N1PK N3K N2P N3P N2 N3PK N2PK N3 0.84 0.87 0.92 1.00 89 98 48 58 70 73 90 4.00 4.09 4.22 4.26 4.49 4.56 .134) .063) .086) . 184) .331) .715) .577) .699) .513) .236) .592) .279) .490) .255) .426) .319) .496) NOPK 0. 74 (.112) NOP 0. 77 (.082) NOK 0. 83 ( .087) NO 0. 87 (.058) NIP 2. 60 (.374) N1PK 2. 95 (.677) NPKT 3. 19 (.567) Nl 3. 39 (.400) N3K 3. 43 (.807) N2K 3. 58 (.709) N2 3. 77 (.490) NIK 3. 87 (.508) N2PK 3. 91 (.269) N3P 3. 96 (.504) N3 4. 05 (.792) N3PK 4. 12 (.499) N2P 4. 46 (.515) NO 0.64 (.108) NOK 0.79 (.243) NOPK 0.86 ( . 198) NOP 0.96 (.152) N1PK 3.28 (.424) NPKT 3. 39 (.559) NIP 3.50 (.444) NIK 3.62 (.630) Nl 3.68 (.446) N2K 4.05 (.303) N2PK 4.06 (.342) N2 4.26 (.215) N3K 4.30 (.286) N3PK 4.39 (.297) N2P 4.43 (.314) N3P 4. 50 (.258) N3 4.55 (.437) NO 0 . 81 (.096) NOK 0.84 (.106) NOP 0.89 (.188) NOPK 1.03 (.208) NIP 2.92 (.242) Nl 2.95 (.379) NIK 3.21 (.428) N1PK 3.35 (.670) N2P 3.53 (.527) NPKT 3.84 (.596) N3 3.84 (.596) N2PK 3.86 (.545) N2 3.95 ( .576) N2K 4.04 (.342) N3P 4.09 (.201) N3PK 4.38 (.322) N3K 4.41 ( . 279) Treatments connected by the same line are not significantly different at p. .01 Values in parenthesis + 1 SD. IV. Phosphorus concentration (2 oven-dry weight). STAND - 1 STAND STAND - 3 STAND - 4 STAND Nl NO NOK N2K N2 N3 N3K NIK NOP N3P N2PK NPKT N3PK NIP N2P N1PK NOPK 10 10 10 11 11 11 12 13 16 17 17 18 18 18 18 18 21 [.014) N2K .09 (.016) NO . 10 [.021) NOK .09 (.010) N3K .11 [.026) Nl .10 (.015) N2K .11 [.010) NIK .10 (.025) Nl .12 [.022) NO .11 (.014) NIK .12 '.006) N2 .11 (.017) NOK .13 .016) N3K .11 (.026) N3 .13 .026) N3 .11 (.022) N2 .14 [ .025) N2PK .17 (.015) NPKT .18 .016) NIP .17 (.020) NIP .19 ; .017) NPKT .17 (.019) N3PK .20 .020) N3P .18 (.018) N1PK .20 ; .015) N3PK .19 (.025) N3P . 20 i .017) NOPK .19 (.022) NOP .20 [.018) N1PK .20 (.025) N2P .20 [.021) N2P .20 (.020) N2PK .20 [.028) NOP .21 (.036) NOPK .23 .013) .025) .020) .021) .018) .023) .036) .029) .011) .016) .014) .028) .017) .046) .033) .020) .046) NOK .12 (.014) NO .13 (.021) N2 .13 (.014) NIK .13 (.018) Nl .14 (.012) N3K .14 (.015) N2K .14 ( .021) N3 .14 (.021) N3PK .18 (.013) N2P .19 (.026) NPKT .19 (.019) N2PK .19 (.021) N1PK .20 (.016) NIP .20 (.015) N3P .20 (.021) NOP .22 (.037) NOPK .24 (.048) NO .10 (.023) NIK .11 (.016) Nl .11 (.016) NOK .11 (.021) N2K .11 (.016) N3K .12 (.018) N3 .12 (.015) N2 .14 (.014) N2P .17 (.019) N1PK .17 (.020) NPKT .18 (.010 N3P .18 (.019) NIP .18 (.024) N3PK .18 (.018) N2PK .19 (.016) NOPK .21 (.044) NOP .23 (.032) Treatments connected by the same line are not significantly different at p. .01, Values in parenthesis + 1 SD. -157-. Potassium concentration {% oven-dry weight). STAND - 1 N2P .30 (.064) N3PK .31 (.049) N3P .31 ( .067) N3K .34 ( .076) N2 .36 (.065) N2PK .38 ( • 107) N3 .39 ( .064) Nl .41 ( .123) N1PK .42 (.085) N2K .43 (.107) NIP .46 (.116) NIK .49 (.103) NPKT .53 (.037) NOP .63 ( .097) NO .64 (.094) NOK .75 (.149) NOPK .84 (.058) STAND - 2 N2 .30 ( .077) N3PK .31 ( .053) .VIP .31 (.063) N2P .31 (.082) N2PK .31 (.082) .V3P .35 (.054) N3 .40 (.123) N3K .40 (.095) Nl .41 (.054) N1PK .43 (.063) N2K .44 (.098) NIK .48 (.079) NPKT .55 ( .047) NOP .59 (.048) NO .60 (.071) NOK .67 (.102) NOPK .76 (.096) STAND - 3 ,V3P .32 (.052) N2 .33 ( .076) N3PK .34 (.055) N2P .34 (.064) N2PK .35 (.051) Nl .37 (.064) N3 .40 ( .051) N3K .40 ( .110) NIP .41 ( .063) N2K .42 ( .099) NPKT .45 ( .042) NO .47 ( .046) NIK .49 (.055) N1PK .53 ( .139) NOP .59 (.134) NOPK .79 (.068) NOK .84 ( .067) STAND - 4 N3 .27 ( .038) N2K .28 (.028) Nl .28 (.045) N2 . 29 (.048) N3PK . 29 (.072) N3K . 32 (.053) N2PK .33 (.068) N3P .35 (.041) N2P . 36 (.051) N1PK .40 (.089) NIP .41 (.072) NIK .43 (.077) NPKT .47 ( .061) NOP .52 ( .020) NO .68 ( . 133) NOK . 74 ( .083) NOPK .91 ( .098) STAND - 5 N3K .27 ( .054) N3P .29 (.049) NIK .31 (.101) N3PK .32 ( .041) N2K .33 (.113) N2P .33 (.066) N3 .34 (.073) N2 .37 (.063) N2PK .38 (.043) NIP .39 (.046) N1PK .39 (.042) NPKT .42 (.052) Nl .42 ( .057) NO .47 (.017) NOK . 75 (.079) NOP .75 (.083) NOPK .82 ( .093) Treatments connected by the same line are not significantly different at p-.Ol. Values in parenthesi s + 1 SD, VI. Calcium concentration (% oven-dry weight). STAND - 1 STAND - 2 STAND - 3 STAND - 4 STAND - 5 N3P .40 (.086) NPKT .34 .(078) N2PK .41 (.141) NOK .44 (.071) NOK .43 (.099) N2K .44 (.070) N2 .44 (.069) N3P .46 (.065) N2P .44 (.071) NO .46 (.069) Nl .44 (.093) NIP .46 (.082) NIK .45 (.069) Nl .47 (.062) N3PK .49 (.116) NOPK .48 ( .082) NO .49 (.112) N2PK .48 ( .092) NIP .50 ( .124) N2P .48 (.082) NOP .50 (.096) N2 .49 (.061) N2K .50 (.070) N3PK .49 (.083) N3K .50 (•105) N3 .49 (.075) N1PK .50 (.138) N3K .49 (.071) NOPK .51 (.079) NOP .50 (.105) N3 .51 (.073) N1PK .50 (.056) NPKT .58 (.069) NIK .51 ( .101) NOK .45 (.081) N3PK .45 (.094) N3PK .46 (.064) N3 .46 (.106) N2 .46 (.092) NO .47 (.084) N3K .47 (.059) N2P .48 (.120) NOP .48 (.041) N2 .50 (.077) Nl .49 (.069) NOK .50 (.146) NPKT .50 (.063) N3P .51 (.086) NO .50 (.057) NIK .51 (.051) N3 .51 (.092) N3K .51 (.135) N2PK .51 (.058) Nl .52 (.076) N3P .52 (.117) NOPK .53 ( .066) NIP .53 (.062) N2K .54 (.127) NOPK .53 (.064) NOP .54 ( . 105) N2K .53 (.036) NPKT .55 ( .037) N2P .53 (.086) NIP .57 (•111) N1PK .61 (.093) N2PK .59 ( .079) NIK .66 (.109) N1PK .63 ( .059) NOP .36 (.070) N2P .37 (.073) N3 .40 (.037) NO .43 (.090) NIP .43 (.078) NIK .46 ( .059) N2 .50 (.106) Nl .51 (.106) N3P .51 (.043) NOK .52 (•174) N3K .53 (.070) N3PK .55 (.108) N2PK .56 ( .127) N2K .56 (.132) NPKT .60 (.164) NOPK .60 (.113) N1PK .62 (.086) CO I VH. Magnesium concentration (% oven-dry weight). STAND - 1 STAND - 2 STAND - 3 STAND - 4 STAND - 5 N2 .07 (.015) N2PK .07 (.017) N3P .07 (.013) NIK .08 (.017) N1PK .08 (.019) Nl .08 (.016) NIP .08 (.022) N3PK .09 (.012) NOK .09 (.023) NO .09 (.016) N2P .09 (.021) N2K .09 (.017) NOPK .09 (.014) N3K .09 (.014) NOP .10 (.012) N3 .10 (.013) NPKT .11 (.010) N2K N3PK NOK N2PK N3K N1PK NIK N3P NOPK NIP Nl N2P NOP N2 NO NPKT N3 07 08 08 08 09 09 09 09 0 0 0 .010) .007) .011) .004) .011) .016) .011) .013) .012) .022) .016) .020) .015) .022) .009) .017) .019) NIP .08 (.020) N3K .09 ( NOPK .09 (.008) NOP .09 ( NOK .09 (.004) N2K .09 ( N3PK .09 (.011) N3PK . 10 ( N3P .09 (.011) NO .10 ( N2PK .09 (.008) NOPK .10 ( N1PK .09 (.019) N1PK . 10 ( N3K .10 (.028) N2P . 10 ( NPKT .10 (.014) N2PK .10 ( NOP . 10 (.009) NIP . 10 ( N2P .10 (.014) N3P . 10 ( NO . 10 (.012) N2 .11 ( NIK .10 (.026) NOK .11 ( Nl .10 (.013) NIK .11 ( N2 .10 (.016) N3 .11 ( N3 .10 (.016) Nl .11 ( NIK .10 (.016) NPKT .13 ( .029) .019) .023) .020) .018) .016) .016) .020) .028) .027) .025) .026) .017) .020) .029) .022) .011) NIK .07 N3PK .07 NOK NO N3K .08 .08 .08 N2PK .08 NIP .09 09 09 09 NIK N3 N2P NOPK .09 N3P .09 NPKT .09 Nl .10 NOP .10 N2 .10 N1PK .11 Treatments connected by the same line are not significantly different at p-.Ol. Values in parenthesis ± 1 SD. -160-APPENDIX I I E f f e c t s o f f e r t i l i z a t i o n on n e e d l e n u t r i e n t c o m p o s i t i o n and n e e d l e w e i g h t f o r e a c h s t a n d . STAND 1 4.80. (G/1000 NEEDLES) 4 5 7 4.00J 3.20.J 2.40. J .60J 0.80J 0.00. J5X 40 1 1 1 T 1 80 120 160 200 240 CONTENT N (MG/1000 NEEDLES) 280 LEGEND. • NO 2 Nl 3 N2 4 N 3 5 NOP 6 NIP 7 N2P 8 N 3 P 9 NOK 10 NIK 11 N2K 1 6 N3K 13 NOPK 1 4 N 1 P K 15 N2PK 16 N3PK 17 NPKT STAND 1 0.32_ 0 . 2 8 J 0 . 2 4 J I? O.ZOJ (G/IOOO NEEDLES) . 4 5 1 3 / / O.I6J 0.12 O.OP. 4.0 i 1 1 T r G.O 10.0 12.0 14.0 16.0 CONTENT P (MG/1000 NEEDLES) LEGEND • NO 2 N l 3 N2 4 N 3 5 NOP 6 M P 7 N2P 8 N 3 P 9 NOK 10 NIK 11 W2\ 12 N3K 13 NOPK 1 4 N 1 P K 15 N2PK 16 N3PK 17 NPKT 20.0 to I STAND 1 1 .ZOJ 1 .00_| 0.80J (G/IOOO NEEDLES) 4 5 3 0.60J 0.40J 0.20. 16.0 20.0 24.0 —1  28.0 CONTENT K 1 32.0 (MG/1000 1 1 36.0 40.0 NEEDLES) 44.0 LEGEND • 2 3 4 5 6 7 NO Nl N2 N3 NOP NIP N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14 N1PK 15 N2PK 16 N3PK 17 NPKT 48.0 STAND 1 0 . 6 0 _ (G/1000 NEEDLES) 4 5 0 . 5 6 J 0 . 5 2 _ | JCR 0 . 4 8 J 0 . 4 4 J 0 . 4 0 . 0 . 3 6 . L JL 16 .0 20.0 1 — 1 1 1 1 ' 24 0 2 B . 0 3 2 . 0 3 6 . 0 4 0 . 0 CONTENT Cfl (MG/1000 NEEDLES) 4 4 . 0 IF.GENP. • NO 2 Nl 3 N 2 4 N 3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 1 2 N 3 K 13 NOPK 1 4 N 1 P K 1 5 N 2 P K 16 N3PK 17 NPKT 4 8 . 0 ON l STAND 1 0.12_ (G/1000 NEEDLES) 4 5 o . io J 0.06 3.2 4.0 4.8 i 3 1 r 5.6 6.4 7.2 6.0 CONTENT MG(MG/1000 NEEDLES) 0.8 LEGEND • NO 2 N l 3 N2 4 N 3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 1 4 N 1 P K 15 N2PK 16 N3PK 17 NPKT 9.6 Ol I STAND 2 (G/1000 NEEDLES) . 4 6 4 40 80 i r 120 160 200 240 CONTENT N (MG/1000 NEEDLES) LEGEND • 2 3 4 5 6 7 280 NO N l N2 N3 NOP NIP N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14 N1PK 15 N2PK 16 N3PK 17 NPKT 320 STAND 2 0.32_ 0.26. 0.24J JP 0.20J (G/1000 NEEDLES) 4 6 5 0. 6J 0.12J 0.08. 2 0 4.0 - i — : 1 r 6 0 8.0 10.0 12 0 14.0 CONTENT P (MG/JOOO NEEDLES) 16.0 LEGEND • NO 2 Nl 3 N 2 4 N 3 5 NOP 6 NIP 7 N 2 P 8 N 3 P 9 NOK 10 NIK 11 N2K 12 >I3K 13 NOPK 1 4 N 1 P K 1 5 N 2 P K 16 N3PK 17 NPKT 18.0 ON I STAND 2 0 . 5 6 - , 0.52 (G/1000 NEEDLES) 0.48-J 0.44J 0.40. 0.36J V 0 . 3 2 _ 1 ' 1 -I 1 1 1 20 0 22 0 2 4 . 0 2 6 . 0 2 8 . 0 3 0 . 0 3 ^ . 0 CONTENT CFKMG/IOOJ NEEDLES) 3 4 . 0 LEGEND • NO 2 N l 3 N2 4 N 3 5 NOP 6 N IP 7 N2° 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 1 4 N 1 P K 1 5 N 2 P K 16 N3PK 17 NPKT 1 1 6 . 0 STAND 2 0.84-, 12.0 16.0 20.0 24.0 28.0 32.0 36.0 40.0 44.0 CONTENT K IMG./1000 NEEDLES) STAND 2 0.18-0.16J 0.14J .IMG 0.12J (G/1000 NEEDLES) o.ioJ 0.0 3.2 q.o 4.8 5.G G.4 1.2 8.0 CONTENT MG(MG/1000 NEEDLES) LEGEND • NO 2 N 1 3 N 2 4 N 3 5 NOP 6 N IP 7 N 2 P 8 N 3 P 9 NOK 10 NJK 11 N2K 1 2 N 3 K 13 NOPK 1 4 N 1 P K 15 N2PK 16 N3PK 17 NPKT STAND 3 4.B0-, (G/1000 NEEDLES) 5 6 4.00J 0.00 i 1 1 r 120 160 200 240 CONTENT N IMG/1000 NEEDLES) LEGEND • 2 3 4 5 6 NO N l N2 N3 NOP NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14 N1PK 15 N2PK 16 N3PK 17 NPKT 320 STAND 3 0.32-0.28J 0.24J 0.20J (G/1000 NEEDLES) 5 6 8 0.16J 0.1ZJ O.OB. 10.0 CONTENT i 1 r 12.0 14.0 16.0 (MG/1000 NEEDLES) L GEND • NO 2 N l 3 N 2 4 N 3 5 NOP 6 N IP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 J3K 13 NOPK 1 4 N 1 P K 15 N2PK 16 N3PK 17 NPKT 20.0 ro I STAND 3 (G/1000 NEEDLES) 5 6 / /* / 12.0 n.o 22.0 27.0 CONTENT 32 0 37.0 42.0 K (MG/1000 NEEDLES) 47.0 LEGEND • NO 2 N l 3 N 2 4 N 3 5 NOP 6 N IP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 1 4 N 1 P K 15 N2PK 16 N3PK 17 NPKT 52.0 to l STAND 3 0.68_ 0.64J (G/1000 NEEDLES) 5 6 / J ° 20.0 24.0 28.0 "i 1 r 32 0 36.0 40.0 44.0 CONTENT CFKMG/1000 NEEDLES) LEGEND • NO 2 N l 3 N2 4 N 3 5 NOP 6 N IP 7 N 2 3 8 N3P 9 NOK 10 NIK 11 N2 12 N3K 13 NOPK 1 4 N 1 P K 15 N 2 P K 16 N3PK 17 NPKT 48.0 STAND 3 0.14_ 0.13_ 0.06. 3.2 4.0 i r 1 r 4.8 5 . 6 B.4 1.2 B.O CONTENT MGIMG/1000 NEEDLES) 8.8 LEGEND • NO 2N1 3N2 4N3 5 NOP 6N1P 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14.N1PK 15N2PK 16 N3PK 17 NPKT 9 . 6 STAND 4 4.80_ (G/1000 NEEDLES) 4.00J 3.20. ZN 2.40J J .60. 0.80. 0.00. 40 1 1 1 1 1 80 120 160 200 240 CONTENT N (MG/1000 NEEDLES) 280 LEGEND • NO 2 Nl 3 N2 4N3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14N1PK 15 N2PK 16 N3PK 17 NPKT 320 STAND 4 0.32-, 0.2BJ 0.24_J 0.20J (G/1000 NEEDLES) 13 0.16J 0.12J 0.06. 2 . 0 4.0 1 1 1 r 6 0 B.O 10.0 12.0 14.0 CONTENT P (MG/1000 NEEDLES) 16.0 LEGEND • NO 2 Nl 3 N2 4N3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14N1PK 15 N2PK 16 N3PK 17 NPKT 1B.0 STAND 4 J .40_ 1 .20. 1.00_| o.eoJ (G/10 0 0.60J 0.40. V 0.20. e.o 12.0 16.0 —I 20.0 CONTENT K i — l 1 24.0 28.0 32.0 (MG/1000 NEEDLES) 36.0 LEGEND • NO 2 Nl 3 N2 4N3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14N1PK 15 N2PK 16 N3PK 17 NPKT 1 40.0 STAND 4 0.68-0.64J (G/1000 NEEDLES) 0.60_J ;CR 0.S6J 0.52J 0.-8J 0.44. 1 1 :—I 1 1 1 16.0 20.0 24.0 28.0 32.0 36.0 40.0 CONTENT CFUMG/1000 NEEDLES) 44.0 LEGEND • NO 2 Nl 3 N2 4N3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2< 12 N3K 13 NOPK 14N1PK 15N2PK 16 N3PK 17 NPKT 48.0 I STAND 4 0. J4_ (G/1000 NEEDLES) 0.13J / 0.12_1 JMG o.n_ i 0.J0. / / / O.O1-. O.OP. / -f 3.2 4.0 4.8 —1 1 1 "I 5 6 6.4 7.2 B.O CONTENT MG(MG/1000 NEEDLES) 8.8 LEGEND • NO 2 l\ 3 N2 4N3 5 NOP 6 NIP 7 N2P B N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14N1PK 15 N2PK 16 N3PK 17 NPK 1 9.6 STAND 5 4.B0_, (G/1000 NEEDLES) 4 . 0.00 i 1 1 r 120 160 200 240 CONTENT N (MG/1000 NEEDLES) LEGEND • 2 3 4 5 6 NO Nl N2 N3 NOP NIP 7 N2P BN3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14N1PK 15 N2PK 16 N3PK 17 NPKT 320 S T A N D 5 (G/1000 NEEDLES) 4 5 6 5 / / 4.0 6.0 1 1 1 1 1 8.0 10.0 12.0 14.0 16.0 CONTENT P (MG/1000 NEEDLES) LEGEND • NO 2 Nl 3 N2 4N3 5 NOP 6 NIP 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14N1PK 15 N2PK 16 N3PK 17 NPKT 18.0 1 20.0 STAND 5 1 .40-, 1.20_ 1.00_| 0.80. (G/4000 NEEDLES) 3 0.60J 0.40J 0.20. 6.0 ]2.0 16.0 1 20.0 CONTENT K i 1 1 24.0 28.0 32.0 (MG/1000 NEEDLES) 36.0 LEGEND • NO 2 Nl 3N2 4N3 5 NOP 6N1P 7 N2 J 8 N3P 9 NOK 10 NIK 11 N2K 12 3K 13 NOPK 14N1PK 15N2PK 16N3PK 17 MPKT l 40.0 STAND 5 0.6SL, (G/1000 NEEDLES) 4 5 0.60J 0.55.4 0.50J 0. 5 J 0.40 0.3S 12.0 i 1 1 r 16.0 20.0 24.0 28.0 32.0 36.0 CONTENT CfUMG/1000 NEEDLES) 40.0 LEGEND • NO 2 Nl 3 N2 4N3 5 NOP 6N1P 7 N2P 8 N3P 9 NOK 10 NIK 11 N2K 12 N3K 13 NOPK 14N1PK 15N2PK 16 N3PK 17 NPKT 44.0 oo I STRND 5 0.13-, 0.12J O.IU JMG O.IOJ (G/IOOO NEEDLES) 4 5 0.09J 0.08J 0.07 3.2 3.7 4.2 1 ' Vi r CONTENT MG(MG/1000 NEEDLES) 

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.831.1-0095955/manifest

Comment

Related Items