Figure ZO. — Besevt hittev- 

 brush surrounded by 

 blaakbrush near 

 Motoqua, Washington 

 County, Utah. 



instances. The seed has a smaller diameter-to-length ratio and is redder than antelope- 

 bitterbrush. Desert bitterbrush averages 20,800 cleaned seeds per pound (46/g) (Plummer 

 and others 1968) . 



In Utah, flowers bloom in May with the fruit ripening by mid-July at lower eleva- 

 tions and by mid-August at higher elevations. Blooming and seed maturity occur earlier 

 on more southerly ranges. However, in California, blooming has been observed as late 

 as August at elevations of 2,740 m (9,000 feet). 



Hybridization: Natural hybrids between desert bitterbrusli and antelope bitterbrush 

 or Stansbury cliffrose are common in areas where the species occur together. Stebbins 

 [1959) reports that desert and antelope bitterbrush form such extensive hybrid swarms 

 in eastern California where their ranges overlap that identity of their parental types 

 is completely obliterated. 



Purshia glandulosa has n = 9 chromosomes (H.C. Stutz, Professor of Botany and 

 Range Science, Brigham Young University, Prove, Utah, personal communication). 



Distribution and Habitat: Desert bitterbrush is found in southern Nevada, southern 

 California, northwestern Arizona, and southwestern Utah. It normally occurs on drier 

 sites than antelope bitterbrush; however, there are major zones of overlap. At lower 

 elevations in southwestern Utah, desert bitterbrush is associated with blackbrush and 

 Stansbury cliffrose and at higher elevations, with big sagebrush, antelope bitterbrush, 

 and Saskatoon serviceberry . 



Use: Desert bitterbrush is an important browse plant throughout its range. It is 

 usually less palatable than antelope bitterbrush, but more palatable than Stansbury 

 cliffrose (Sampson and Jespersen 1963). 



Desert bitterbrush readily sprouts following burning. Shoots are formed from 

 deeply embedded roots, which make desert bitterbrush particularly valuable in stabiliz- 

 ing readouts and similar surfaces where several feet of topsoil have been removed 

 (fig. 31). This shrub is especially recommended for restoration of mine spoil areas 

 and other seriously disturbed sites because of its sprouting characteristics and ability 

 to grow in soils of low fertility. Ecotypes with a wide range of adaptation are being 

 sought for use in the revegetation of widely scattered disturbed areas. 



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