32 STATE BOARD OF FORESTRY. 



British Columbia: 



Universal : 



International : 



(Applied to sections with taper allowance of V' in 8', and 

 constructed for \" saw-kerf.) 



Preston : 



(1 _ >2 0) 





' L = B.M. (Small logs) 



^B.M. (Large logs) 



Doyle : 



McKenzie : 



[i- 



7r(D a) 3 



L+ C=B.M. 



(w -f k) (t -f fc)J 4 X 12 



Where k = saw-kerf in inches. 



Where t = average thickness of lumber sawed, in inches. 



Where w = average width of lumber sawed, in inches. 



Where a = constant. 



Where C = constant included to compensate for excessive taper in 



small logs. 

 To be applied to 8' sections with taper allowance of e" in /'. 



It will be observed that of the above rules the Doyle and the Baxter 

 are the two extremes. The Doyle rule has an enormous slab allowance 

 with extremely small allowance for sawdust, (4.5%) ; where the Baxter 

 rule has a small slab allowance and a very large allowance for saw- 

 dust, (33.8%). 



