The soil formed in residuum from chert, argillite, shale, altered rhyolitic tuff and andesite. Slopes are 2 to 75 percent. Elevations are 4,200 to 7,600 feet. The climate has warm, dry summers and cool, moist winters. These are Burrito and Favret soils.
Burrito soils have clayey-skeletal argillic horizons.
Favret soils are moderately deep and have less than 35 percent rock fragments. Livestock grazing and wildlife habitat. The present vegetation is black sagebrush, bottlebrush squirreltail, Indian ricegrass and Thurber needlegrass. These soils are not extensive. MLRA 24, 27.