site Basic Record 

 ELK GULCH 



From the cemetery in Dillon (1 mile east of town), proceed on the gravel Sweetwater Road K 

 miles east to a dirt road and gate on the south side of the Sweetwater Road. Go through the 

 gate and follow the dirt road 6.5 miles to a jeep trail on a forested ridge. Take this jeep 

 trail 0.4 mile south and park. The site is 0.2 mile to the south. 



The site occurs on soils derived from peridotite and granite gneiss parent materials. The 

 peridotite portion of the site was mapped in 1970 as having greater than 1000 ppm nickel (map 

 of Elk Creek Nickel Claims, K. Stout, Butte, MT). Artemisia tridentata/Festuca idahoensis 

 connunities occur on both parent materials, but the occurrences on peridotite appear to be 

 relatively sparse. 



COUNTY: Beaverhead 



USGS QUADRANGLE: ELK GULCH 



TOWNSHIP-RANGE: 009S007U SECTION: 02 

 QUARTER/ADDITIONAL SECTIONS: 



BOUNDING RECTANGLE: S: 450433N N: 450502N E: 1122520W U: 1122555W 



BOUNDARY JUSTIFICATION: The primary boundary contains the full range in soil nickel concentrations from 

 below 100 ppm to above 1000 ppm, and follows drainage bottoms and divides. 



APPROXIMATE ACREAGE: 100.00 



GENERAL RATING: 5 



No G2, G2 or G3 elements present. 



BIODIVERSITY SIGNIFICANCE: B4 



BC-ranked occurrences of G5 elements. 



OTHER VALUES: V2 



A wide range of soil nickel contents occurs across the site. High nickel concentrations have 

 been shown to affect vegetation composition and structure. This site is important in showing 

 the interaction of shrub-steppe vegetation and soil nickel. 



PROTECTION URGENCY: PI 



Mine expansion in the areas with high nickel content is currently underway. It is likely this 

 site will soon be severely disrupted. 



MANAGEMENT URGENCY: Ml 



Within the site, it may be desirable that at least one area with good- condition vegetation be 

 preserved from mining disturbance. 



CONSERVATION INTENT: 



PROTECTION COMMENTS: 



LAND USE: Cattle have heavily grazed the area in the past, especially the flatter surfaces. However, it 

 does not appear that cattle have been present on the site in 1990 and 1991. Mining activity is 

 intensifying in the area. 



NATURAL HAZARDS: None. 



EXOTICS: No exotic species currently appear to pose a threat to this site. 



OFF-SITE LAND USES: Mining of adjacent areas may result in weed influx to the site and could alter 

 the site's hydrologic and nutrient regimes. 



INFORMATION NEEDS: More intensive investigation is necessary to verify whether or not there is a 



peridotite parent material effect on vegetation composition and structure. Also, 

 the site should be more thoroughly surveyed for the presence of rare plants. 



MANAGEMENT NEEDS: Closely regulate mining and livestock grazing so that such anthropogenic factors 

 do not mask natural vegetation /soil responses. 



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