Available Timber 



An analysis of timber availability based on many of the factors that 

 affect timber management shows timber yields in Working Circle 3 may be re- 

 duced by 16 percent due to nontimber use constraints. 



A difficult and potentially expensive task in any forest inventory is 

 determining the amount of timber that is actually available for harvesting. 

 Every acre of state and private forest land is not available for continuous 

 timber harvesting and probably never will be unless wood becomes much more 

 valuable. 



The first step in assessing timber availability is to group the forest land 

 into availability classes. This is done based on various combinations of land 

 use influence zones, ownership groups, and topographic characteristics. 

 Some of the criteria used to delineate availability classes include water in- 

 fluence zones, travel influence zones, slope percent, and elevation. These 

 availability classes are then assigned to one of three land classes based on 

 each land class's definition and the characteristics of the different availability 

 classes. Table 33 shows the criteria used to assess timber availability in 

 Working Circle 3. 



Land Classes 



The commercial forest land in Working Circle 3 was grouped into three 

 land classes (Green 1976): 



1. Standard: land available and operable now that is not subject to any 

 nontimber use impacts that might affect timber growing costs or ex- 

 pected yields; 



2. Special: land available and operable now, but with ecological or other 

 use constraints that might affect the cost of growing timber, expec- 

 ted yield, or both; and 



3. Marginal: land potentially available and operable, or both, but not 

 now expected to be harvested because of excessive development 

 costs, low product returns, or resource protection constraints. 



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