ash bush n Also ash weed, Mexican ash bush [From the grayish foliage; prob loan translation of cenizo n 2 (< Span ceniza ash)]
A silverleaf n 8 (here: Leucophyllum frutescens).
1903 Amer. Inst. Mining Engineers Trans. 33.981 csTX, It [=the Reynosa formation] is covered by brown sands, and in places by Pleistocene deposits, but its presence is manifested by frequent exposures, and by a white or ashy-gray plant called by the citizens the ash-bush, or ash-weed, which in this area is an almost certain indication of the presence below it of the limestone, limy sands or limy clays. 1934 San Antonio Express (TX) 29 July sec A 1/3, Desert Willow and Seniza, Mexican ash bush, which always bloom at or after rains, are the most prominent among the bloomers. Both have light lavender blooms and bees just swarm on them. 1960 Vines Trees SW 921, Leucophyllum . . frutescens. . . Other vernacular names are Ash-bush [etc]. 2004 Kerrville Daily Times (TX) 29 July sec A 3/1, Texas sage (Leucophyllum frutescens) . . has many more common names than any other plant I know. . . Texas Ranger, Texas silverleaf, purple sage, Texas rain sage, barometer bush, cenizo, Palo cenizo, ash-bush, wild lilac, senisa, cenicilla, and hierba del cenizo.