Beaverhead National Forest lands in the Tendoys are 

 mostly at higher elevations flanking the crests of the range, 

 but some lower elevation foothills and stream courses are 

 represented. Forest lands on White Pine Ridge were not 

 included in this survey. The lower elevations peripheral to 

 the National Forest and in Muddy Creek Basin are mostly BLM 

 and state lands. Private land in the range is limited to the 

 periphery and a few inholdings along Muddy and Kate Creeks and 

 in the northern foothills. 



The Tendoy Mountains were formed by folding and faulting 

 of Precambrian, Paleozoic and Mesozoic strata as described by 

 Geach (1972) and Alt and Hyndman (1986). The north-south 

 trending Red Rock fault is evidenced by the steep eastern 

 flank of the range, visible from Interstate 15 between Dell 

 and Red Rock. Exposed bedrock in the mountains and foothills 

 includes some precambrian granite and gneiss, along with 

 extensive beds of Mississippian and Pennsylvanian sedimentary 

 rocks, mostly limestone and quartzite, respectively. Much of 

 the lower foothills and the Muddy Creek basin are covered by 

 Tertiary sediments (conglomerates, shales, sandstones, 

 limestones, and tuff). A limited area of younger Tertiary 

 volcanics is exposed in the vicinity of Sourdough Point. 

 Quaternary deposits include alluvial flood plains, terraces, 

 and fans, and extensive talus and boulder fields mass-wasted 

 from steep cliffs. 



The climate regime of the Tendoy Mountains vicinity is 

 semi-arid with cold winters and relatively warm summers. Data 

 from the nearby station at Lima (elevation 6,265 feet) are 

 taken to approximate the climate of the lower elevations in 

 the study area (from Geach 1972). Average annual 

 precipitation was 9.92 inches with a seasonal peak in May and 

 June. The average monthly temperature in January was 16.3° 

 F, and in July was 63.0° F. The climate becomes colder and 

 wetter at the higher elevations, and prevailing conditions are 

 greatly modified by local aspect and topography. 



Vegetation in the Beaverhead National Forest in the 

 Tendoys consists of extensive coniferous forests, grasslands, 

 and shrublands, and limited areas of wetlands. The forests 

 are primarily Douglas fir {Pseudotsuga menziesii) at lower 

 elevations and limber pine (Pinus flexilis) and Engelmann 

 spruce {Picea engelmannii) at higher elevations. A small area 

 restricted to non-calcareous bed rock is covered by lodgepole 

 pine (Pinus contorta) . The grasslands include small areas of 

 low elevation canyon bottoms dominated by Great Basin wild rye 

 {Elymus cinereus) , rather extensive montane and sub-alpine 

 areas dominated by bluebunch wheatgrass {Elymus spicatus) and 

 Idaho fescue (Festuca idahoensis) , and at the highest 

 elevations, wind swept alpine-like vegetation dominated by low 

 growing graminoids such as purple reedgrass (Calamagrostis 



