Biennials or short-lived, usually monocarpic perennials, 10–100 cm; taprooted with simple or branched caudices. Stems 1–several, spreading to erect, bushlike or forming low rounded mounds, gray-tomentose with appressed feltlike trichomes; branches 0–several, inclined to ascending, stiff. Leaves: blades elliptic to ovate, 10–25 cm, strongly undulate, usually broadly pinnatifid, lobes entire or coarsely few-toothed or-lobed, main spines abrupt, 1–4 mm, faces gray-white-tomentose with appressed feltlike, non-septate trichomes; basal present or withered at flowering, winged-petiolate; principal cauline well distributed, winged-petiolate to sessile, gradually reduced, bases clasping with expanded auricles; distal reduced, spines to 8 mm. Heads 1–many, erect, terminal on branches in subcapitate to congested, corymbiform arrays, closely subtended by clustered, ± leafy bracts. Peduncles 0–7 cm. Involucres hemispheric or campanulate, 3–4 × 4–6 cm, densely arachnoid. Phyllaries in 8–10 series, imbricate, linear, abaxial faces without glutinous ridge; outer and mid bases short-appressed, margins spiny-ciliate, apices long, spreading to erect, spines straight, 2–5 mm; apices of inner flattened or spine-tipped, serrate to scabrid, sometimes pectinately fringed. Corollas white to pale yellow, 20–34 mm, tubes 11–15 mm, throats 5–8 mm, lobes 5–8 mm; style tips 3–4 mm. Cypselae light–brown to black, 5–7 mm, apical collars whitish, 0.2–0.3 mm; pappi 15–25 mm. 2n = 34.
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