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GRASSHOPPER STUDY AREA 



Surveys in the Grasshopper Study Area yielded the highest number of records for different 

 sensitive species among the tliree areas, reflecting the area's botanical diversity and extent of 

 appropriate habitat. New records were documented for ten species, in addition to those already 

 known, for Astragalus scaphoides, Lesquerella pulchella, Penstemon lemhiensis, Bannack State 

 Park species, and various others. 



The Grasshopper Study Area sensitive species are made up primarily of state and regional 

 endemics (Astragalus scaphoides, Astragalus terminalis, Lesquerella pulchella, Lomatium 

 attenuatum, Oryzopsis contracta, Penstemon lemhiensis, Taraxacum eriophorwn, and 

 Townsendia nuttallii). Secondarily, the area consists of peripheral species. Phacelia incana and 

 Sphaeromeria argentea are centered in the Great Basin/Salmon Plains. Also present are southern 

 cordilleran species which are at their northern limits. One of the other peripheral species, 

 Erigeron linearis, is a western species at its eastern limits. 



Astragalus scaphoides (Jones) Rydb. 



BITTERROOT MILKVETCH 



Bean Family (Fabaceae) 



CONSERVATION STATUS 



U.S. Fish and Wildlife Service: 3C (USDI Fish and Wildlife Service 1993). Ranking 

 signifies that the species has "proven to be more abundant or widespread than previously 

 believed and/or.... (is) not subject to any identifiable tlireat" and is based in large part on 

 the numbers of populations in Idaho. 



Bureau of Land Management: Astragalus scaphoides was included on the BLM draft 

 list of sensitive species for Montana distributed for review in 1995. 



Montana Natural Heritage Program rank: G3 SI (critically imperiled in the state) 

 prior to this study. There are now 17 Montana occurrences of this species, only one of 

 which is extirpated. The number of new records provides basis for reranking it as "S2" 

 (imperiled in the state), assuming that the extant populations are not subject to immediate 

 tlireat. 



DESCRIPTION: Astragalus scaphoides is a stout herbaceous perennial with several erect 

 stems, 2-6 dm (8-24 in.) high, from a branched rootcrown. Pimiately-compound leaves are 10-25 

 cm (4-10 in.) long with 15-21 narrowly elliptic leaflets. Foliage is glabrous to sparsely hairy. 

 Infloresences are borne in the axils of upper leaves and have 15-30 spreading, crowded flowers 



