b. U.S. Forest Service: none 



c. Bureau of Land Management: Astragalus scaphoides is 



included on the BLM's list of proposed sensitive 

 species for Montana (USDI Bureau of Land Management 

 1993) . 



2. State: The Montana Natural Heritage Program ranks the 



species G3 and SI (Heidel 1994). The global ranking is a 

 reflection of vulnerability due to a restricted range. 

 Within Montana, the species is considered critically 

 imperiled due to extreme rarity and/or other factors. 



C. GEOGRAPHIC DISTRIBUTION 



1. Species range: Astragalus scaphoides is a narrow endemic 

 restricted to the foothills of the Bitterroot Mountains 

 and adjoining valleys in Lemhi County, Idaho and across 

 the mountains in southwestern Beaverhead County, Montana 

 (Barneby 1964) . 



2. Distribution in Montana: Astragalus scaphoides is known 

 only from southwestern Beaverhead County, in the 

 drainages of Grasshopper, Horse Prairie, and Medicine 

 Lodge creeks and the upper Beaverhead River. There are 

 now a total of 14 Montana occurrences entered in the 

 Biological Conservation Database. 



3. Occurrences in the Tendoy Mountains: One population was 

 found on the Beaverhead National Forest in the drainage 

 of Kate Creek (012). An Element Occurrence Record and 

 map showing the precise location of the population is 

 included in Appendix D. In addition, two populations 

 occur on BLM land in the range, in the vicinities of 

 Baker Canyon (Vanderhorst 1995a) and Johnson Gulch 

 (Vanderhorst and Lesica 1994). The species is thus known 

 only from the western flank of the range constituting the 

 drainage of Medicine Lodge Creek. 



D. HABITAT 



1. Associated vegetation: In Montana, Astragalus scaphoides 

 grows in sagebrush grasslands usually dominated by 

 Artemisia tridentata (big sagebrush) and Elymus spicatus 

 (bluebunch wheatgrass). Other shrub species which are 

 subdominant or in some cases replace big sagebrush in 

 these habitats include Artemisia tripartita , Artemisia 

 nova, and Chrysothamnus nauseosus . Other common or 

 subdominant grasses at the sites include Stipa comata, 

 Oryzopsis hymenoides , Festuca idahoensis , and Poa 

 secunda. Among the most conspicuous forb associates are 

 other species of milkvetches including Astragalus 



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