Figure 17. — Left to right, shadscale saltbush, shadscale saltbush x Castle Valleij clover 

 saltbush hybrid. Castle Valley clover saltbush. 



Hanson (1962) found a number of A. confertifolia x A. corrugata hybrids along 

 roadsides. He examined 420 saltbushes growing along a road at a station near Price, 

 Utah. Of these, 215 [51 percent) were shadscale, 170 (44 percent) were mat saltbush, 

 28 (7 percent) were cuneate saltbush, and 7 (1.7 percent) were hybrids between shad- 

 scale saltbush and mat saltbush. The hybrids grew only a short distance from the 

 pavement and all were under 3 years of age, having grown since road margins were last 

 graded. None of the hybrids were found in adjacent stabilized vegetation. We have 

 observed putative hybrids along Utah Highway 10, south of Emery, Utah. 



The shadscale-mat saltbush hybrid is a woody shrub with decumbent to ascending 

 branches. The branches do not root when in contact with the soil; and when mature, 

 they form weak to strong unbranched spines. The bark is gray, soft, and spongy. The 

 pale gray-green, densely scurfy, evergreen leaves measure 7 to 20 mm long, 4 to 9 mm 

 wide, and are oblanceolate to elliptical or spatulate. The fruiting bracts are 8 to 

 10 mm long and 5 to 8 mm wide with fewer than eight tubercules scattered about the base 

 or with tubercules absent. The bracts are united for about one-half of their length 

 (fig. 7). This hybrid is nearly sterile. Out of 500 large utricles from the Price 

 station, Hanson (1962) found only two with seeds. 



Hanson (1962) found a single hybrid of A. confertifolia x A. gardneri growing 

 intermixed with its probable parents along U.S. Highway 30 south, 3.3 km (2 miles) 

 east of Ft. Bridger, Wyoming. According to him, the hybrid was a low shrub similar in 

 general aspect to Gardner saltbush. However, it has a mass of spinose, unbranched, 

 ascending twigs, and large bracts 8 mm long and 4 mm wide. These features are more 

 like those of shadscale. 



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