economically feasible. It was recognized that demands on the land for 

 agricultural production and other purposes as well as size of farm unit 

 and other factors might tend to keep some land in uses not now considered 

 as the most desirable from the physical standpoint. Estimates of acre- 

 ages for 1975 included the acreage of Federally owned land expected to be 

 transferred into private ownership. 



Estimates of land use changes were made by land capability units. Infor- 

 mation on land capability was obtained by interpreting information on 

 soils obtained from sample soil surveys, A land capability unit is a 

 grouping of soils that are nearly alike in potential for agricultural 

 use, plant growth, and response to treatment or management. In making 

 capability interpretations, soils are grouped first into capability clas- 

 ses identified by Roman numerals I to VIII. Olass I land includes soils 

 having no problem that limits use. The remaining classes have increasing 

 limitations in use. Capability classes are divided into subclasses based 

 on the dominant kind of problem. These are shown by lower case letters 

 with (e) indicating an erosion problem, (w) a problem of excess water, 

 (s) a soil limitation, and (c) a climatic limitation. The addition of 

 an Arabic number following the class and subclass symbol identifies the 

 capability unit. 



Secondary problems were not indicated by the land-capability symbol but 

 were recognized by interpreting the soil conditions. This identification 

 of the kind of land and the problems needing treatment was used in esti- 

 mating land use changes. For further explanation of the land-capability 

 classification see page 32 of the Appendix. 



Estimates of land use changes were made by land-resource units and then 

 added together to give county totals. A land-resource unit is a geo- 

 graphical area of land, at least several thousand acres in extent, 

 characterized by a particular combination or pattern of soils (includ- 

 ing slope and erosion), climate, water resources, land use, and types 

 of farming. Such a unit may occur in one continuous area or in 

 segments. 



U 



