covered with a gray-green, fairly compact tomentum. The leaves are broadly linear, 

 ranging from 4 to 8 cm long and 3 to 10 mm wide, which makes them the largest leaves of 

 the species (fig. 48d) . The involucral bracts are 7 to 8 mm long, mostly obtuse, 

 nearly glabrous, and arranged in rather obscure ranks (fig. 36b). The yellow corollas 

 are about 1 cm long and have a minutely pubescent throat. The achenes are densely 

 pubescent. Mountain rubber rabbitbrush was reported by Hall and Clements (1923) to be 

 "apparently rare and confined to Utah." However, we have found it to be fairly wide- 

 spread at higher elevations in Utah and parts of Nevada (East Humboldt Range, Elko 

 County; and Mt. Charleston, Clark County) as part of the lower subalpine vegetation 

 (fig. 54). L. C. Anderson (letter 3/30/76) considered our Nevada specimens to be ssp. 

 alb'ioaulis . So far as we can determine, these specimens do not differ in any important 

 respects from ssp. salioifolius growing at its type location (Strawberry Valley, 

 Wasatch County, Utah). It extends down to the foothills in parts of its range where 

 it may be found intermixed with ssp. alh-ioaulis and gvaveolens (Plummer 1977). Moun- 

 tain rubber rabbitbrush appears to be the most palatable subspecies of the four common 

 subspecies, saliai f alius j albioaul-isj graveolenSj and oonsimilis in Utah (Plummer 1977), 



Other less common subspecies which, however, have locally large populations include 

 junceuSj hololeuaus, and le-iospermus . Subspecies junaeus is a nearly leafless. 



Figure 53. — Mountain 

 vubber rabbitbrush 

 (C. nauseosus ssp. 

 salicifolius j growing 

 at .the Snow Field 

 Station. 



50 



