RULES OF THUMB FOR VOLUME DETERMINATION 

 By F. R. Mason 



For a long time the writer felt the need of a rough rule of 

 thumb that would give approximately the volume of standing trees 

 based on a simple mathematical computation. It is a well-known 

 fact that it is an endless task to try to memorize volume tables 

 when a number of species are being dealt with constantly. Many 

 of the existing and generally published tables have been tried out 

 by checking them against tree measurements and they are usually 

 found to be inadequate, varying anywhere up to 100 per cent in 



error for individual trees and often up to 30 per cent for groups 

 of trees when applied to the timber in Idaho and Montana, using 

 the Scribner Decimal C rule. 



The writer had occasion to make up a volume table for Douglas 

 fir and at the time the scaled volume of individual trees was noted 

 there was also noted the scale of the butt log of each tree, together 



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