Timberland Quality Class 



Approximately 'f40,100 acres, or liO percent, of the commercial softwood 

 timberland in the working circle was rated as good or excellent for timber 

 production based on a classification system developed for Montana. The forest 

 industry ownership group had S** percent of its timberland rated as excellent 

 or good, the greatest amount among ownership groups on a percentage basis. 

 The other private ownership had the most acreage rated as good or excellent 

 among the three major ownership groups. 



Timberland quality classes in this analysis are used to rate commercial 

 timberlands according to their relative value for producing timber. The 

 rankings are based primarily on factors that indicate the operability and 

 productivity of the forest. Four quality classes — excellent, good, fair, and 

 poor — were used. To avoid confusing the findings of this timberland rating 

 effort with those of other state and federal land management agencies, the 

 term "prime timberlands" was not used. 



Class Definitions 



The criteria used to place timberlands into the appropriate quality 

 classes are as follows: 



Excellent timberlands 



— have a potential productivity that is greater than or equal to 85 cubic feet 

 per acre per year; 



— have a slope that is less than or equal to 40 percent; 



— have a good (class I) or medium (class II) landscape stability rating; 



— are less than or equal to 7,000 feet in elevation west of the Continental 

 Divide and less than or equal to 8,000 feet east of the Divide. 



Good timberlands 



-- do not meet the requirements for excellent timberlands; 



— have a potential productivity that is greater than or equal to 50 cubic feet 

 per acre per year; 



— have a good (class I) or medium (class II) landscape stability rating; 



— have a slope that is less than or equal to 40 percent if potential produc- 

 tivity is less than 85 cubic feet per acre per year; 



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