Figure 66. — Spineless hopsage poputoxion in }ioi'ti\h)estp-rn Ayiteii'>vt^ 



Valley, Sanpete County, Utah. 



only one produced viable seed (table 1). Unfortunately, none o£ the resultant seedlings 

 survived. These progeny are essential for verifying the nature of the purported crosses 

 We are confident that our continuing hybridization work, associated with better care of 

 any resultant seedlings, will yield the needed progeny. Spineless hopsage is tetraploid 

 with a chromosome number of 2n = 36 (C. L. Pope and E. D. McArthur, data on file at 

 Shrub Sciences Laboratory, Provo, Utah) . 



Distribution and habitat: Spineless hopsage is generally restricted to shale 

 formations of the Upper Colorado River Drainage. It favors silty clay loam soil 

 derived from shales. Collotzi (1966) noted it occurred under mildly alkaline (pH 7.4 

 to 7.7) conditions. Other populations occur on similar soils in central Utah (fig. 36) 

 and in southeastern Colorado. 



Use: This species may be used as browse by livestock and big game. It germinates 

 and produces seedlings readily; but, unless protected, these are quickly taken by 

 rodents and rabbits. These small mammals have shown a high preference for the seedlings 

 established at several locations. Kingsbury (1964) lists spineless hopsage as a 

 possible secondary or facultative selenium absorber. As such, it could be mildly 

 poisonous in areas where the soil contains selenium. 



Grayia spinosa (spiny hopsage) 



Spiny hopsage is an erect, diffusely branched, spinescent shrub from 3 to 12 dm in 

 height (fig. 37). It differs in many respects from spineless hopsage, but both species 

 have similar utricles (fig. 7, 35, 38). 



29 



