Range condition refers to the state of vegetation on a range site rela- 

 tive to the theoretical climax association for that range site. For each 

 range site, the Soil Conservation Service has identified species that de- 

 crease, increase and then decrease, or invade under grazing. The relative 

 percentage by weight of plants in these categories determines the condition 

 of a range site, or its subdivision. 



Estimates of species composition by dry weight* made at the time of 

 reconnaissance sampling, and other reconnaissance data were used for deter- 

 mining range condition. Range sites were taken from the ongoing Soil Con- 

 servation Service soil mapping effort in McCone county. Range condition 

 mapping was done on an overlay to the soil map at a scale of 1:24,000. 



* Estimating weight is hazardous (Daubenmire 1968), but estimating each 

 species contribution relative to the total weight may be more reliable. 



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