Class 40 . --Areas medium to fully stocked with desirable trees and with 30 percent or more of 

 the area controlled by other trees and/or conditions that ordinarily prevent occupancy by 

 desirable trees. 



Class 50 . — Areas poorly stocked (16.7 to 59 percent) with desirable trees, but fully stocked 

 with growing stock trees. 



Class 60 . --Areas poorly stocked with desirable trees, but with medium to full stocking of 

 growing stock trees. 



Class 70 . — Areas nonstocked (less than 16.7 percent) or poorly stocked with desirable trees, 

 and poorly stocked with growing stock trees. 



Class 80 . --Low-risk old-growth stands. 



Class 90 . --High-risk old-growth stands. 



Nonstocked . --Areas less than 16.7 percent stocked with growing stock trees. 



Productivity 



Productivity class . --A classification of forest land in terms of potential growth in cubic 

 feet of fully stocked natural stands. 



Stand-Size Classes 



Sawtimber stands . — Stands at least 16.7 percent stocked with growing stock trees, with half 

 or more of total stocking in sawtimber or poletimber trees, and with sawtimber stocking at least 

 equal to poletimber stocking. 



Poletimber stands . --Stands at least 16.7 percent stocked with growing stock trees in which 

 half or more of this stocking is in poletimber and/or sawtimber trees, and with poletimber 

 stocking exceeding that of sawtimber. 



Sapling-seedling stands . --Stands at least 16.7 percent stocked with growing stock trees in 

 which more than half of the stocking is saplings and/or seedlings. 



Nonstocked land . --Commercial timberland less than 16.7 percent stocked with growing stock 

 trees. 



Class of Timber 



Growing stock trees . --Live trees of commercial species qualifying as desirable or acceptable 

 trees. (Excludes rough, rotten, and dead trees.) 



Desirable trees . --Growing stock trees (1) having no serious defect in quality to limit 

 present or prospective use for timber products; (2) of relatively high vigor; and (3) containing 

 no pathogens that may result in death or serious deterioration before rotation age. 



Acceptable trees . --Growing stock trees meeting specified standards of size and quality, but 

 not qualifying as desirable trees. 



Rough trees . --(1) Live trees that do not contain at least one 12- foot saw log or two 

 noncontiguous saw logs, each 8 feet long or longer, now or prospectively, and/or do not meet 

 Rocky Mountain regional specifications for freedom from defect primarily because of roughness or 

 poor form; and (2) all live trees of noncommercial species. 



