356 THE STUDY OF PLANT COMMUNITIES * Chapter XII 



ment under certain usages. They are used to determine the kind, 

 degree, and time of grazing, and for determining the grazing 

 capacity of a range. When the plants present are considered in 

 conjunction with soil conditions and the climax, the previous use 

 of the range can be interpreted and its potential usefulness under 

 proper management can be predicted. 



FlG. 190. Winter range (Atriplex nuttallii) in Colorado, so badly over- 

 grazed that there is practically no vegetation left and gullying is serious on 

 all the slopes. Such depletion is obvious to anyone, but recognition of the 

 onset of these conditions should be possible for those who know the indica- 

 tors.— U. S. Forest Service. 



Misuse of range lands is obvious in late stages, but it is difficult 

 to recognize when it first begins and should be corrected. Among 

 the indicators that must be watched for are thinning of cover and 

 a lowered vitality of the principal species, replacement of good 

 forage plants by inferior ones, close grazing of species that ordi- 



