Figure 9. — Leaves of 

 silver sagebrush. Top^, 

 A. cana ssp. viscidula; 

 bottom. A. cana ssp. 

 cana. The longer leaf 

 is 4 cm long. 



Leaves on the vegetative branches are 1 to 10 mm wide and 2 to 8 cm long, linear 

 to linear-oblanceolate, entire or occasionally with 1 or 2 irregular teeth or lobes, 

 silver-canescent becoming slightly viscid with age (figs. 9, 10). Leaves on the flower- 

 ing stems are similar, but they may be slightly smaller, especially on the upper parts 

 of the stems. The foliage emits a mild to pungent aromatic odor when crushed. 



Numerous heads are arranged into dense, narrow, leafy panicles, sometimes reduced 

 to raceme or spikelike inflorescence (fig. 10). Each head contains 4 to 20 disc flowers. 

 Ray flowers are lacking. Achenes are granul if erous . Blooming occurs during August and 

 September. Cleaned seed averages 4,900 per gram (2,220,000 per pound). 



Hybridization .--Silver sagebrush occurs in both diploid (2n = 18) and tetraploid 

 (2n = 36) forms (Ward 1953) . Putative natural hybridization between subspecies of 

 A. cana {cana and viscidula) and other shrubby species of Artemisia have been reported 

 (Ward 1953; Beetle 1960; Hanks and others 1973). 



Distribution. -Silver sagebrush occurs over approximately 13,790,000 hectares 

 (53,221 square miles) from British Columbia to Saskatchewan, south to Nebraska, Colo- 

 rado, and New Mexico, and west to Oregon and California on valleys, plains, foothills, 

 and mountains up to 3,050 meters (10,000 feet) (Beetle 1960). 



Wse. --Silver sagebrush is important throughout its range as a browse shrub and is 

 used quite extensively by livestock and big game, particularly when other food is scarce. 

 In the western Great Plains area, silver sagebrush is an important antelope survival 

 food. Like big sagebrush, this species has been used by white settlers and Indians for 

 fuel. Silver sagebrush has been used as an ornamental in England (Hall and Clements 

 1923) . 



11 



