Site Basic Record 

 UPPER BIG SHEEP CREEK 



From Dell, proceed south along the 1-15 frontage road following the Big Sheep Creek signs. 

 Continue 1.7miles to a T intersection, and take the fork leading southwest. Proceed 8 miles to 

 a Y intersection and take the road leading south 7.5 miles. The site is north of the road. 



The site is a steep, southerly limestone talus slope in various stages of becoming stabilized 

 by vegetation. A portion of the site is unvegetated talus and limestone outcrops. The 

 vegetation is characterized by shrublands (Artemisia tridentata series; A. arbuscula series; 

 and Cercocarpus ledifolius series) and woodlands in the Pinus flexilis series. 



COUNTY: Beaverhead 



uses QUADRANGLE: CABOOSE CANYON 



TOWNSHIP-RANGE: 015S010U SECTION: 10 

 QUARTER/ADDITIONAL SECTIONS: N2 



BOUNDING RECTANGLE: S: 443238N N: 443305N E: 1124748U U: 1124855W 



BOUNDARY JUSTIFICATION: The boundary contains a relatively continuous occurrence of limestone talus, and 

 extends from Big Sheep Creek (and road) to the ridge crest. This includes all 

 upland areas which might support occurrences of rare plant species. 



APPROXIMATE ACREAGE: 200.00 



GENERAL RATING: 2 



Site supports five SI plant species: Agastache cusickii, Arenaria Kingii, Hutchinsia 

 procumbens, Mimulus suksdorfii, and Phacelia incana. 



BIODIVERSITY SIGNIFICANCE: B2 



Currently only known occurrence in Montana of Agastache cusickii (G3G4/S1). Site contains a 

 better occurrence of Phacelia incana (G3G4/S1), the only Montana location for Hutchinsia 

 procumbens (G5/S1) and a representative site for Mimulus suksdorfii (G5/S1). 



OTHER VALUES: V4 



PROTECTION URGENCY: P3 



Gravel pit development threatens the lower portions of the site. The steep, rocky slopes 

 minimize the incidence of livestock use; however, some of the Cercocarpus ledifolius present is 

 being heavily browsed by deer. 



MANAGEMENT URGENCY: M4 



Deer populations may need to be controlled to prevent overbrowsing of Cercocarpus and reduce 

 the possibility of increased erosion. 



CONSERVATION INTENT: Recommend establishment of a BLM ACEC 



PROTECTION COMMENTS: The BLM is aware of the site and met with L. Roe to evaluate the best location 

 for a public gravel pit. A decision was made after a field evaluation. Signs 

 were to be posted at the designated gravel pit. 



LAND USE: Nine different gravel pits were established on the slopes below the populations. One was chosen 

 by the BLM (after a field evaluation) to be designated for use. It is not known if the site 

 selected is currently the only one used. Since the slopes of the site are so steep, rocky, and 

 unstable, use other than by wildlife has been severely limited. Cattle use has been moderate in 

 the Artemisia tridentata/Agropyron spicatum communities on the less steep lower slopes of the 

 site. 



NATURAL HAZARDS: Limestone cliffs and loose talus pose hazards. 



EXOTICS: Very few exotic species are currently present on the site. 



OFF-SITE LAND USES: The riparian area beneath the slope along the creek is in poor condition from 

 extensive use by cattle. Improvement of grazing practices might reduce the 

 numbers and types of exotics likely to invade the riparian area, and hence the 



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