pratensis and the abundance of Carex parryana ssp. idahoa (Table 

 1) . Four of the five sites where Carex parryana ssp. idahoa was 

 most abundant had forb cover less than 20%, although mean forb 

 cover for all 14 sites was 42%. These results indicate that 

 grazing is likely having a negative impact on the sedge. 



Taken together my observations suggest that Carex parryana 

 ssp. idahoa responds to grazing like many palatable graminoids. 

 It can persist with ungulate grazing pressure, but as grazing 

 becomes strong enough to cause an increase in forbs and Poa 

 pratensis, there will be a decrease in this rare sedge. 



Literature Cited 



Hansen, P. L. , R. D. Pfister, K. Boggs, B. J. Cook, J. Joy, and 

 D. K. Hinkley. 1995. Classification and management of Montana's 

 riparian and wetland sites. University of Montana School of 

 Forestry Miscellaneous Publication No. 54, Missoula. 



Hermann, F. J. 1970. Manual of car ices of the Rocky Mountains 

 and Colorado Basin. USDA Forest Service Agriculture Handbook 

 374, Washington D.C. 



Lesica, P. and S. J. Shelly. 1991. Sensitive, threatened and 

 endangered vascular plants of Montana. Montana Natural Heritage 

 Program Occasional Publication No. 1. Helena, Montana. 



Murray, D. F. 1969. Taxonomy of Carex Sect. Atratae 

 (Cyperaceae) in the Southern Rocky Mountains. Brittonia 21: 55- 

 76. 



Ross, R. L. and H. E. Hunter. 1976. Climax vegetation of 

 Montana based on soils and climate. USDA Soil Conservation 

 Service, Bozeman, MT. 



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