1). The lowest point is at 6,150 ft near the confluence of Sage 

 Creek and the Red Rock River, while the highest point is ca . 

 8,100 ft at Vinegar Hill in the eastern portion of the study 

 area. Parent materials throughout the study area are the 

 Beaverhead gravels and the Beaverhead conglomerate, loose 

 aggregations of stream-rounded pebbles and cobbles in a matrix of 

 clacareous cement (Alt and Hyndman 1986) . There are outcrops of 

 Madison limestone in the Basin Creek area. Soils are generally 

 calcareous and well drained except on stream terraces and in some 

 broad, nearly level basins. 



Climate of the area is semi-arid. The closest weather 

 station is Lima at the southwest edge of the study area at 6,275 

 ft. Mean temperatures for January and July are 16.6 and 62.6° F 

 respectively, and mean annual precipitation is 10.74 in (NOAA 

 1982) . Annual precipitation in the low mountains northeast of 

 Lima is estimated to be 16 in. (USDA-SCS 1981) . May and June are 

 the wettest months, while the monthly average precipitation 

 during the winter is less than 0.5 in (NOAA 1982). 



Vegetation of the Sage Creek area is primarily grassland and 

 sagebrush grassland. Stipa comata and Agropyron spicatum are 

 dominant grasses on sandy soils, while Festuca idahoensis and A. 

 spicatum are dominant where textures are loamier. Artemisia 

 tridentata ssp. vaseyana is common on more mesic slopes with 

 deeper, less stony soils. Stands of Pinus flexilis occur on some 

 of the higher hills in the Basin Creek area. Stands of dry 

 Pseudotsuga menziesii occur on cool slopes at higher elevations. 

 There are stands of mountain mahogany (Cercocarpus ledifolius/ 

 Agropyron spicatum) on warm slopes at the head of Big Spring and 

 Little Spring gulches. Some stream terraces supported stands of 

 Artemisia tridentata ssp. tridentata, with an understory of 

 Elymus cinereus and Agropyron smithii; however, most of these 

 stands have been degraded or lost. Broad terraces along Sage 



