provided the basis for the mean-acre volumes by classes. Total volume 

 estimates were derived by applying the mean-volume estimates to the re- 

 vised acres by classes, 



•The re survey area and volume statistics for the eight counties are based 

 on the initial survey cover-type area modified by sample line transects 

 and volume sample plots shown in the following table? 



County Area Volume 



Chains of transect Number of plots 



Bonner l620„0 282 



Boundary 1921.0 198 



Clearwater 2090.0 408 



Kootenai 858.5 198 



Latah 607.0 135 



Lewis 174.5 42 



Nez Perce 259.0 54 



Shoshone 1732.0 414 



Total 9262.0 1731 



Transect courses <, location of section corners and plots, and other in- 

 formation were recorded on available aerial photographs and field forms 

 to facilitate relocation and future measurements. 



The 1943-44 resurvey in Benewah County consisted of collecting data on 

 about 4000 l/20=acre sample plots five chains apart along parallel 

 cruise lines spaced three miles apart and disposed in a north-south 

 direction. A six-year adjustment for cutting and growth was applied 

 to the resurvey estimates to bring Benewah County statistics up to a 

 comparable date with the other counties in North Idaho. 



In resurveying Idaho County a complete new cover type map was made. 

 The mapping was done in the field on aerial photographs and later 

 transferred to 2-inch-to-the-mile township maps. As in the initial 

 survey the area was classified by nonforest land and forest land with 

 subclasses by type,, stand-size s stocking* age ? and site classes. Finally, 

 the various cover classes were tabulated by ownership and summarized. 



For volume estimates in Idaho County the method was similar to that of 

 the eight counties already described with the exception that only two 

 l/5-acre sample plots were measured at each location. A total of 237 

 locations, or 474 sample plots 3 were measured. 



Growth 



Gross and net growth were derived from increment borings of 1513 sam- 

 ple trees and mortality tallies on each sample plot measured for 



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