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density, max. latewood density, and ring width. There was n.s.d. in av. wood density between
treatments. There were significant between-treatment differences in MOE and MOR. Heavy
thinning (during the juvenile wood formation phase) reduced latewood fibre length by 26.5%.
Min. earlywood density and max. latewood density were the most important components of ring
density.
67. Brand, D.G. 1986a. A competition index for predicting the vigour of planted Douglas-fir in
southwestern British Columbia. Canadian-Journal-of-Forest-Research 16(1): 23-29.
Keywords: planting operations
tree/stand health
growth
Abstract: As a method of quantifying brush competition, data from 124 planted Douglas
firs, age 1-5 yr, were used to derive a competition index to predict changes in tree vigour
measured as a relative production rate. The index, which includes measures of brush proximity,
relative ht. and % ground cover, appears to act as a measure of light interception around the tree
crown. Tree vigour was found to be largely a function of the age of the tree from planting and the
competition index. Foliage-based measures of growth vigour were related more strongly to the
index than measures of b.a. or ht. The index has potential for assessing interspecific competition
problems on suitable sites. Caution must be used in extrapolating results outside Douglas fir
plantations on moist rich sites in coastal BC.
68. Brand, D.G. 1986b. Competition-induced changes in developmental features of planted Douglasfir
in southwestern British Columbia. Canadian-Journal-of-Forest-Research 16(2): 191-196.
Keywords: planting operations
tree morphology
tree physiology
growth
Abstract: From measurements in 1- to 5-yr-old plantations, developmental characteristics
of Douglas fir were tested against a competition index based on measures of the brush canopy
surrounding individual trees. The most promising characteristics for assessing competition were
specific leaf area, the allometric relationship of ht. to b.a. and bud production on nodal shoots.
Measures of foliar N and leaf internode length were less well correlated with the competition
index. Comparing these results with those of laboratory studies indicated that, on the study sites,
brush competition effects on planted trees are expressed through adaptation to reduced light
intensity. Developmental variables relating to moisture and nutritional status were not as strongly
related to the competition index. This may reflect reduced tree demand or secondary brush
canopy effects.
69. Brandeis, T.J., M. Newton and E.C. Cole. 2001. Underplanted conifer seedling survival and
growth in thinned Douglas-fir stands. Canadian-Journal-of-Forest-Research 31(2): 302-312.
Keywords: planting operations
thinning
commercial thinning
site preparation
chemical preparation
release treatments
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