The Intermountain Tall Sagebrush Shrubland [M169] found in the Colorado Plateaus and Arizona-New Mexico Mountains ecoregions, has an open to dense (10-80% cover) shrub canopy (<2 m (7 ft) tall) dominated by big sagebrush. Some stands of this shrubland are codominated by fourwing saltbush, shadscale saltbush, rubber rabbitbrush, spiny hopsage (Grayia spinosa), greasewood, or spineless horsebrush (Tetradymia canescens). The herbaceous understory is variable and characterized by a sparse to dense (5-50%) cover of grasses such as Indian ricegrass and needle and thread. Stands occur from 900 to 2,500 m (2,950-8,200 ft) in elevation on a variety of terrains that include flat to steeply sloping upland slopes on alluvial fans and terraces, toeslopes, lower and middle slopes, draws, badlands, foothills, and rocky slopes. Soils vary from deep and well-developed to shallow, rocky, and poorly developed.