Figure 7. — Weights of holes for 

 dominants 4 inches and less 

 in d.h.h. Almost all estimates 

 for individual species differ 

 from the group average hy less 

 than 20 percent of the group 

 average. 



12 3 



D.B.H. (IN) 



dominants, the extremes in estimated weights at 4 inches d.b.h. are 43 lb for western 

 larch and 16 lb for Engelmann spruce. Differences in wood density and tree height 

 account for the difference in weight. 



Limited data from this study suggest that bole weights of intermediates tend to 

 weigh more than dominants. Except for western redcedar, equations in table 5 yield 

 greater bole weights for intermediates than dominants. For western redcedar and 

 ponderosa pine, differences in bole weights between dominants and intermediates were 

 statistically nonsignificant according to a test of differences between pooled resid- 

 uals of dominants and intermediates and a composite regression (90 percent confidence 

 level) . For grand fir and Douglas-fir, bole weights were significantly different be- 

 tween dominants and intermediates (99 percent confidence level) . 



Whole Tree Weights 



For seedlings and small saplings, separation of crovsn weights from bole weights 

 may be undesirable for some purposes. Thus, the equations in table 6 were derived to 

 estimate whole tree weights. Weight estimates for individual species are within about 

 15 percent of the average for the group of species. Weights of intermediate grand fir 

 can be predicted using the equation for dominant grand fir. 



Ponderosa pine, Douglas-fir, Engelmann spruce, and subalpine fir weighed notice- 

 ably more than the other species (fig. 8). For trees over 5 ft tall, average d.b.h. 

 and age of the heaviest species group were greater than the other species. Although 

 rate of height growth for the heaviest species group was less, more dry matter in 

 crowns and boles had been produced. Proportions of foliage and branchwood are summa- 

 rized in appendix 111. 



18 



