sagebrush is much less common and occurs only at scattered locations. This is as ex- 

 pected because black sagebrush is commonly associated with basin big sagebrush but only 

 occasionally with mountain big sagebrush. 



Although black sagebrush is treated in this paper as a separate species, as was 

 done by Beetle (1960), some authorities consider both black and low sagebrush to be 

 subspecies of big sagebrush (Hall and Clements 1923; Davis 1952; Harrington 1954), 

 while Ward (1953) considers black sagebrush to be a subspecies of A. arhusQula. The 

 indication that both black sagebrush and low sagebrush can apparently hybridize with big 

 sagebrush indicates a close affinity of these members of section Tvidentatae . 



Distribution and habitat .--Black sagebrush covers approximately 11,220,000 hectares 

 (43,301 square miles) in the 11 western States (Beetle 1960). It is most abundant at 

 elevations from 1,500 to 2,400 meters (4,900 to 7,900 feet) and normally grows on 

 drier, more shallow stony soil than basin or mountain big sagebrush (fig. 17) (Beatley 

 1976). Type locality is listed as "Medicine Bow, Carbon County, Wyoming" (Abrams and 

 Ferris 1960). 



Use . --Black sagebrush is generally considered highly palatable especially to sheep, 

 goats, antelope, and sage grouse. It is held in high regard as browse for sheep, goats, 

 deer, and antelope on winter ranges in Utah, Colorado, and New Mexico. In some areas 

 it is browsed by cattle, but cattle show less preference for it than other animals. 

 Palatability seems to vary with color. In Nevada, a gray-green form is heavily grazed; 

 whereas, a darker glossy-green form is much less grazed (Brunner 1972). That palat- 

 ability varies with color forms has been supported by some of our work (Stevens and 

 McArthur 1974). 



Black sagebrush is an aggressive natural spreader from seed and provides good 

 ground cover for stabilizing soil. Under proper management, stands depleted by heavy 

 grazing recover within less than 10 years. Some large areas in Nevada formerly occupied 

 by black sagebrush have been invaded by Utah juniper [Juniperus osteosperma) and single 

 leaf pinyon pine (Pinus monophylla) . 



Artemisia pygemaea Gray (pigmy sagebrush) 



Pigmy sagebrush is a dwarf, depressed, evergreen, cushionlike shrub less than 2 dm 

 tall (fig. 18). Bark on older stems becomes dark brown and fibrous. On young branches 

 the bark is nearly white to straw-colored and somewhat puberulent. 



Figure 18. — Pigmy sage- 

 brush (A. pygmaea/) 

 growing at the Snow 

 Field Station. 



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