Element Name: Thlaspi parvif lorum A. Nels. 



Common Name: Small-flowered pennycress 



Range: Endemic to southwest Montana, northwest Wyoming and 

 central Idaho. In Montana this species is known from Beaverhead, 

 Madison, Park and Silver Bow counties. 



Element Rank: G3/S2 



Federal Status: USFS Region 1 Sensitive 



Local Occurrence: I located two populations of Tj. parvif lorum 

 in moist grasslands and meadows on gentle slopes or alluvial 

 terraces in the Moose Town area (Fig. 2) . The eastern population 

 occurred in a somewhat drier site and was estimated at 100-1,000 

 plants. The western site was estimated at 1,000-10,000 plants. 

 Associated plant communities are Potentilla f ruticosa / Festuca 

 idahoensis and Potentilla fruticosa / Juncus balticus . 



Comments: I searched extensively for this species in the Moose 

 Town area, but in spite of large areas of apparently potential 

 habitat, I located only two populations. However, T\. parvif lorum 

 is inconspicuous unless it is blooming, and it blooms very early 

 and has completely disappeared by mid-summer. Thus, I may not 

 have located all populations in the study area. 



Both Ti parvif lorum sites are subject to livestock grazing. 

 The effects of grazing on the species are not known. 



Element Name: Carex vallicola Dewey 



Common Name: Valley sedge 



Range: Eastern Oregon to southwest Montana and western South 

 Dakota, south to California, Utah and Mexico. In Montana the 

 species is known from Beaverhead, Gallatin, Lewis & Clark, 

 Madison, Park and Silver Bow counties. 



Element Rank: G5/S2 



Federal Status: None 



Local Occurrence: I located one population of C\_ vallicola in 

 mesic high-elevation grassland in the Limekiln Hill area (Fig. 

 3). The population was estimated to be 100-1,000 plants. The 

 associated plant community is Festuca idahoensis / Agropyron 

 caninum . 



Comments: This small population of C_j_ vallicola is in an area 

 that has extensive mining exploration. The area is also subject 



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