||This article needs attention from an expert in Ecology. (December 2009)|
Shrub-steppe is a type of low rainfall natural grassland. Shrub-steppes are distinguishable from deserts, which are too dry to support a noticeable cover of perennial grasses or other shrubs, while the shrub-steppe has sufficient moisture levels to support a cover of perennial grasses and/or shrubs.
The shrub steppes of North America occur in the western United States and western Canada, in the rainshadow zone between the Pacific Coast Ranges, Cascades, and Sierra Nevada on the west, and the Rocky Mountains on the east. They extend from south-central British Columbia down into southeastern Washington state, eastern Oregon, and eastern California, and across through Idaho, Nevada, and Utah into western Wyoming and Colorado, and down into northern and central New Mexico and northern Arizona. Growth is primarily low-lying shrubs, such as sagebrush.
Shrub-steppe ecoregions of North America include:
- Great Basin shrub steppe: sagebrush steppe in eastern California, central Nevada, western Utah, and southeastern Idaho.
- Mojave Desert sky island sagebrush steppe: the Mojave sky islands (with pinyon-juniper woodland) in southeastern California; and small portions of southern Nevada, southwestern Utah, and northwestern Arizona.
- Colorado Plateau shrublands: western Colorado, northern and central New Mexico, northern Arizona, and eastern Utah
- Eastern Cascades shrub steppe (including the Columbia Basin): in south-central Washington state, eastern Oregon, northeastern California, northern Nevada, central Idaho.
- Wyoming Basin shrub steppe: in central Wyoming, reaching into south-central Montana, northeastern Utah, southwestern Idaho, and northwestern Colorado.
- Okanagan shrub steppe: in the Okanagan Valley in south-central British Columbia, and the southern Similkameen Valley in south-central British Columbia and north-central Washington state.
- Arid Lands Ecology Reserve (in Washington state in the US)
- Deserts and xeric shrublands
- Sagebrush steppe
- Temperate grasslands, savannas, and shrublands