1). Thus, the land inventory provided important 

 dual properties: analysis could be accomplished 

 on an ecological basis; and it could be trans- 

 formed to meaningful geographic units for 

 evaluation and presentation. 



Table 1. — Productivity and conditioyi classes 



Forest ecosystems 



Range ecosystems 



Productivity 





Wood 



Herbage 



cubic feet per acre per year 

 120 + 



85 to 119 



50 to 84 

 to 49^ 



First quartile 

 Second quartile 

 Third quartile 

 Fourth quartile 



Condition 





Timber 



Range 



Nonstocked 



Good 



Seedling, sapling, and pole'^ 

 Sawtimber^ 



Fair 

 Poor 



^ Commercial forest types that produce less than 20 

 cubic feet are classified by the USDA Forest Service 

 as noncommercial. Forest lands in this category were 

 placed in the low productivity class. 



' Stands with seedlings and saplings or poles having 

 trees up to about 9 inches in diameter. 



' Stands with sawlogs having at least 50 percent of 

 the trees above 9 inches in diameter; in the Far West, 

 11 inches. 



The actual compilation procedures differed 

 for the forested and nonforested ecosystems 

 (fig. 2 and fig. 3). For the forested ecosystems, 

 acreages were derived from preliminary forest 

 survey data for 1970 Timber Review, USDA 

 Forest Service, and rearranged to fit the re- 



F— 389158 



Figure 2. — The Oak-hickory ecosystem on Mark Twain 

 National Forest, Missouri. 



F— 440852 



Figure 3. — The Desert shrub ecosystem in Utah. 



source unit classification scheme. As an example, 

 acreages of the three timber stand-size classes 

 for poles, saplings, and seedlings had to be 

 aggregated to form one "condition" class. Also, 

 within the publicly owned lands in the Forest 

 Survey data were State, county, and municipal 

 lands which had to be transferred to the non- 

 Federal category. 



The acreage information for the nonforested 

 ecosystems was taken from inventories kept by 

 the various Federal agencies. Land data for the 

 nonforested lands in the National Forest Sys- 

 tem were taken from an inventory made in 1967 

 by the USDA Forest Service to provide infor- 

 mation for the Public Land Law Review Com- 

 mission (University of Idaho 1969). Data 

 submitted by field units included classification 

 of about 18 million acres within 2,200 range 

 allotments by eleven standard vegetation types, 

 seven grazing capacity classes, and four range 

 condition classes. The sample was expanded 

 and the vegetation types cross-referenced to 

 ecosystems. Following is the procedure used to 

 accomiolish this: 



1. Kiichler types were matched with the 

 broad vegetation types used in existing range 

 inventories. 



2. Where two or more Kiichler types fell in 

 the same range inventory type, but were includ- 

 ed in different FRES ecosystems, proportionate 

 percentages were developed as follows : An ace- 

 tate transparency with State and National For- 

 est boundaries was laid over Kuchler's map and 

 proportions were determined for National For- 

 est System lands in each State. A set of per- 

 centages was thus developed for each State. 

 The sample data were then expanded to the 

 total population. 



3. Since the inventories of the "range" and 

 "forest" ecosystems were developed from dif- 

 ferent sources, neither of which represented the 

 total area of the National Forest System, the 

 sum of the two did not necessarily add up to 



