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additional indirect evidence of the impact grazing has on these 

 plants. Conservation management for these plants should a) 

 reduce overall levels of grazing on BLM land in the Horse Prairie 

 area (decrease stocking rates, increase rest periods), especially 

 in areas where overgrazing is evident, and b) designate 

 population areas to be preserved. Combining these tactics would 

 be the most effective means of preserving known populations of 

 sensitive plants as well as their potential habitat and overall 

 biodiversity. Occurrences chosen for specific conservation 

 management should include the largest and healthiest populations 

 in the least degraded habitat (e.g. Clark Canyon School Section, 

 008, for Astragalus scaphoides , and Roberts Gulch, 015, for 

 Penstemon lemhiensis) . 



During the early part of the season I tried to identify BLM 

 sites with wetland plant communities in fair to excellent 

 condition which warranted return trips for surveys at the 

 appropriate time later in the season. Most wetland plants mature 

 late in the summer, and often, fruiting material is necessary for 

 reliable identification (e.g. for sedges). Although most 

 wetlands in the study area were heavily degraded by cattle 

 grazing even in June, I identified sites in apparently good shape 

 in the vicinities of Bloody Dick Creek, Frying Pan Creek, 

 Exchange Pasture, and around Clark Canyon Reservoir. I made 

 return trips to all of these sites in August, however, effective 

 surveys for sensitive plants could only be conducted at Bloody 

 Dick Creek and Clark Canyon Reservoir. The other sites were 

 heavily grazed at a late date in the season and few plant species 

 could be identified. For effective surveys of these habitats to 

 be conducted, the sites will need to be rested for at least the 

 entire season prior to the survey. Cattle grazing is 

 concentrated around water sources and within the study area there 

 are virtually no wetlands in native condition. 



Noxious weeds are not as well established in Beaverhead 

 County as in other parts of Montana, perhaps due to the 

 relatively high elevation, isolation, and active prevention 

 programs in the county. However, weeds are a threat to sensitive 

 plants and to the native flora in general and they are likely to 

 become more established in Beaverhead County in the future. 

 Sensitive plants may be especially susceptible to weed 

 infestations because they often have poor competitive ability and 

 low levels of reproduction. Currently, the population of 

 Astragalus terminalis in the study area is threatened by an 

 invasion of sweetclover (Melilotus officinalis) along with other 

 exotic weeds, which originates on private land. Sweetclover was 

 introduced to this continent and is often seeded for erosion 

 control, but increasingly it is becoming invasive in native plant 

 communities in Montana. Management of this problem will reguire 

 cooperation between the BLM and the private landowners. 

 Revegetation of disturbed areas, especially when they are 

 adjacent to populations of sensitive plants or to intact native 



