Sagebrush scrub
Sagebrush scrub is a vegetation type (biome) of mid-to-high elevation Western United States deserts characterized by low-growing drought-resistant shrubs including the sagebrush (Artemisia tridentata) and its associates.[1][2] It is the dominant vegetation type of the Great Basin Desert (Great Basin shrub steppe),[2] occurs along the margins of the Mojave Desert, including in the southern slopes of the Sierra Nevada and the Transverse Ranges, in California,[2] and occurs in the Colorado Plateau and in the Canyonlands, where it may be referred to as cool desert shrub.[3]
It often occurs adjacent to piñon-juniper woodland communities, between 4,000 and 7,000 feet elevation, where annual precipitation is 8"-15", much of it snow.[4]
It sometimes occurs in pure stands of sagebrush or with associates that vary from region to region.[2] Sagebrush scrub may occur as an understory of pinyon-juniper woodland.[2]
Mojave Desert
[edit]In the Mojave Desert, sagebrush associates include saltbrush (Atriplex spp.), rubber rabbitbrush (Ericameria nauseosa), green ephedra (Ephedra vidris), hop-sage (Grayia spinosa), and bitterbrush (Purshia glandulosa).[2]
Sierra Nevada
[edit]Sagebrush scrub occurs in relatively deep soils along the Sierra-Cascade axis, running from Modoc County to San Bernardino County.[4]
In the Sierra Nevada range, in California, sagebrush associates include bitterbrush (Purshia tridentata), curl-leaf mountain-mahogany (Cercocarpus ledifolius), and rabbitbrushes (Chrysothamnus spp., Ericameria spp.).[1] Average summer temperatures are in the 80's Fahrenheit, and 10-20 degrees F in the winter.[1] It can survive on 7 inches of annual precipitation and so is generally below the piñon-juniper woodland vegetation type, which requires 12 to 20 inches.[1] Its range is 4,200 to 7,000 feet in the eastern Sierra Nevada range, in California.[1]