TIMBER ESTIMATING IN THE PACIFIC 



NORTHWEST 



By H. J. Brown 



TIMBER estimating varies from 

 the rapid, inexpensive prelim- 

 inary to the detailed, elaborate, 

 costly method of the total tree 

 count. In making a preliminary, one 

 may run once through a 40 by either 

 estimating the trees in a given strip or 

 by generally sizing up the timber. In 

 making a total tree count it is necessary 

 to run through a 40 8 or 12 times, 

 counting the trees on each side of the 

 compass line for a sufficient distance to 

 cover the entire area. 



In the wide range from the one-ruK 

 preliminary to the total tree count with 

 its 8 or 12 times through a 40, there 

 are any number of systems, limited 

 only by the ingenuity of the estimator, 

 so that when one reads of a new sys- 

 tem having been developed it is not to 

 be taken too seriously. 



The first estimating on the Pacific 

 Coast was done on a basis of one run 

 through a 40, but as the timber in- 

 creased in value more care was taken 

 with the estimating until now the basis 

 is a 2, 4 or 8 times run through a 40, 

 at a cost of from 12 cents to $1.00 per 

 acre. 



The most frequent systems used are : 



(1) Counting the trees either in 

 strips or in circles and obtaining the 

 total by multiplying the average tree 

 by the number of trees. 



(2) Counting the trees either in 

 strips or in circles and treating each 

 tree as a unit to obtain the totals. 



(3) Taking a tree here and there as 

 a base and by much criss-crossing of 

 the area between the compass lines 

 seeing the entire acreage. This plan is 

 subject to a great many variations and 

 is used mostly by men of long expe- 

 rience in the woods. It is considered 

 by many largely a matter of intuition. 

 Nevertheless, its accuracy at times is 

 almost startling. 



The strip and circle methods are 



fundamentally the same, as they are 

 both based on the counting of trees. 

 Some prefer the circle method, as they 

 can count the trees with more accuracy 

 while standing on one spot than while 

 moving and counting them in a strip. 

 This, however, is largely a matter of 

 training. The strip method is the only 

 one used when making an entire tree 

 count. The difference in the method 

 of estimating lies in counting the con- 

 trast and then multiplying by an aver- 

 age tree in contrast to estimating each 

 tree and adding for the total. 



To obtain the amount in individual 

 trees is also largely a matter of per- 

 sonal choice. There are two general 

 systems : 



(1) Certain "rules of thumb" de- 

 veloped by the individual cruiser and 

 which have been found to produce sat- 

 isfactory results. 



(2) The use of the volume table 

 which is based on an ideal tree, thereby 

 making it necessary to have the trees 

 conform to the volume table and not 

 the volume table to the tree. This table 

 is based on diameters running from 12 

 to 90 inches, or higher, carrying a dif- 

 ferent number of logs and a varying 

 taper for each diameter class. In 

 other words, adding the contents of the 

 scale of the individual logs to get the 

 contents of the tree. 



For example : 



4 logs or 3 logs or 



128 foot tree 96 foot tree 



Taper Contents Taper Contents 



32' log B. M. 32' log B. M. 



Butt 3" 4,784 3" 3,960 



Diameter 4" 4,010 4" 3,458 



36" 5" 3,316 5" 2,994 



6" 2,722 6" 2,568 



To use this table one must measure 

 down trees for taper and length and 

 use the volume table accordingly. The 

 diameter of standing trees can be deter- 

 mined by the use of a diameter tape. 



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