Smithsonian Contr. Knowl. 5(6): 72. 1853.
Perennials, 30–90 cm. Stems branched from bases, pubescent. Leaves opposite; petioles 1–5 mm; blades 3-nerved from bases, oblong, obovate, or ovate, (15–)30–80 × 10–35 mm, bases cordate or truncate, margins crenate-serrate, apices acute to obtuse, faces sparsely pubescent and gland-dotted. Heads erect, usually in loose, paniculiform arrays, sometimes borne singly. Peduncles 2–15 mm, hispid to hirsute. Involucres cylindric to narrowly campanulate, 8–12 mm. Phyllaries 17–20 in 3–5 series, pale green, often purplish, 5–9-striate, unequal, margins narrowly scarious-ciliate (apices acute to acuminate); outer lance-ovate (sparsely pubescent), inner narrowly lanceolate (glabrous). Florets 10–16; corollas purplish, 7–9 mm. Cypselae 3–4 mm, densely pubescent to velutinous; pappi of 40–52 white, barbellate bristles. 2n = 18.
Phenology: Flowering Jul–Oct.
Habitat: Oak woodlands, open limestone hillsides
Elevation: 1500–2000 m
Ariz., N.Mex., Mexico.