LITERATURE CITED 



Ayensu, E., and R. DeFillips. 1978. Endangered and threatened plants of the 

 United States. Smithsonian Inst, and World Wildlife Fund. 403 pp. 



Coupland, R. , N. Skoglund, and A. Heard. 1960 Effects of grazing in the 

 Canadian mixed prairie. Int. Grassland Congr. Proc. 8:212-215. 



Daubenmire, R. 1959. A canopy-coverage method of vegetation analysis. 

 Northwest Sci. 33(l):43-64. 



, 1968. Plant communities. Harper &. Row, New York. 300 pp. 



Montana Department of Natural Resources and Conservation. 1979a. Circle West 

 vegetation monitoring study. First Annual Report for the period August 14-26, 

 1978. Circle West Tech. Rep. No. 3. 



. 1979b. Circle West vegetation monitoring study. Second Annual Report 



for the period August 14-24, 1979. Circle West Tech. Rep. No. 5. 



Pfister, R. , and S. Arno. 1980. Classifying forest habitat types based on 

 potential climax vegetation. For. Sci. 26(l):52-70. 



Prodgers , R. 1978. Circle West vegetation baseline study. Circle West Tech. 

 Rep. No. 1. Montana Dept . Nat. Res. & Cons., Helena. 



. 1981. Monitoring air pollution impacts to prairie vegetation and cereal 



grains. Unpublished MS. 



Reed, M. , and R. Peterson. 1961. Vegetation, soil and cattle responses to 

 grazing on northern Great Plains range. USDA For. Serv. Tech. Bull. No. 1252. 

 79 pp. 



Soil Conservation Service. 1976. National Range Handbook. A USDA publication. 



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