Perennials, 100–200 cm (bases woody). Stems branched, stipitate-glandular. Leaves alternate; petioles 20–35 mm; blades 3-nerved from bases, deltate-ovate or rhombic-ovate, 20–140 × 10–100 mm, bases truncate to cordate, margins irregularly dentate, apices acute, faces gland-dotted or glandular-pubescent. Heads in paniculiform arrays. Peduncles 3–18 mm, stipitate-glandular. Involucres cylindric to campanulate, 7.5–8.5 mm. Phyllaries 22–26 in 5–6 series, greenish, often purple-tinged, 3–4-striate, unequal, margins narrowly scarious (apices obtuse to acute); outer ovate to lanceolate (glandular-hirtellous, shorter than inner), inner linear-lanceolate (glabrous). Florets 15–24; corollas pale yellow-green or greenish white, 5–6.5 mm. Cypselae 2–3 mm, strigose; pappi of 30–35 white, barbellulate bristles. 2n = 18.

Flowering Aug–Oct. Near streams, canyon bottoms; 1100–1800 m; Ariz., N.Mex.; Mexico.