growing with such shrubs as big sagebrush, snakeweed, various subspecies of rubber 

 rabbitbrush (ssp. saliaifoliuSj dlhioaulis, and gvaveolens') , other subspecies of low 

 rabbitbrush {stenophyllus^ viscidiflovus, and pub e rut us) , Greenes rabbitbrush (C. 

 greenei) , and Parry rabbitbrush (C. parry i) . 



Chrysothcormus visaidiflorus ssp. puherulus (hairy low rabbitbrush) is a small 

 shrub up to 5 dm high with yellowish to green, finely pubescent branches (fig- 58). 

 Its linear-filiform to linear leaves are sparsely to densely pubescent with scabrid- 

 ciliate margins, and are usually twisted or revolute. The leaves are up to 2 mm wide 

 and up to 3 cm long (fig. 56b). Flower heads are borne in small compact cymes with 

 densely pubescent branches. Involucral bracts are about 5 to 6 mm long, lanceolate to 

 oblong, acute to obtuse, and are usually marked with a thickened greenish spot near 

 their tips. Hairy low rabbitbrush occurs on dry plains, valleys, and foothills, espe- 

 cially on poorer soils and disturbed areas. Its range extends from British Columbia to 

 Montana northward to New Mexico, Arizona, Nevada, and eastern California. This sub- 

 species is most abundant in the big sagebrush communities of western Utah, Nevada, and 

 southern Idaho. However, it has been found growing in one locality or another with most 

 of the other subspecies of low rabbitbrush, shadscale, winterfat, halogeton {Halogeton 

 glomeratus) , and occasionally with pinyon and juniper. 



Chrysotharmus visaidiflorus ssp. stenophyllus (narrowleaf low rabbitbrush) is a 

 low, glabrous shrub up to 3 dm high with white bark. Leaves are linear-filiform, often 

 twisted, viscidulous, 1 mm or less wide, 1 to 3 cm long, and glabrous except for the 

 usually scabrid and revolute margins (fig. 56c). The branches of the small, compact 

 cymes are glabrous. Involucral bracts are 4 to 6 cm long, not keeled, and lance-oblong. 

 Narrowleaf low rabbitbrush is rather common on most desert ranges, particularly in the 

 southern portion of the Great Basin where it sometimes composes more than a third of the 

 vegetative cover (Cook and others 1954) . On these ranges this subspecies is usually 

 found in the sagebrush type on poorer soils and disturbed sites, but is also found grow- 

 ing with halophytes such as shadscale, fourwing saltbush {Atriplex canescens) , grease- 

 wood, and halogeton. The species has special usefulness for providing cover on disturbed 

 ranges in arid climates. 



Chrysotharmus visaidiflorus ssp. visaidiflorus (stickyleaf low rabbitbrush) is the 

 largest subspecies of low rabbitbrush. Mature shrubs are usually more than 5 dm tall, 

 whereas the other subspecies are normally all under 5 dm. Its branches, leaves, and 



Figure 58. — Broom snake- 

 weed (X. sarothraej 

 (right) growing next 

 to hairy low rabbit- 

 brush (C. viscidi- 

 florus ssp. puberulusj 

 near Ephraim^ Sanpete 

 Co., Utah. 



57 



