Disc florets 8-18; corollas white. Pappi of (16-)18-25 bristles 1-2 mm. 2n = 34, 68, 170. Flowering spring-fall. Crevices of igneous bluffs and boulders; 1200-1900 m; Tex. Variety albiflora is found throughout much of Brewster County, eastern Presidio County, and extreme southern Jeff Davis County.