Annual herbs, mostly 100–200(–400) cm tall, usually forming dense stands. Leaves on 3–8 cm long petiole, lamina ± deltate to triangular–ovate, 7–38 cm long, 7–30 cm wide, sometimes 3– or 5–lobed, glabrous or soft pubescent beneath. Capitula 3–4 (–8) cm across, on 11–27 cm long peduncles. Phyllaries 14–21, (2–) 3–seriate, lanceolate to linear; outer 17–30 mm long, 4–7.5 mm wide, apices acute, usually densely puberulent beneath, inner ones similar to outer, 16–28 mm long, 5–8 mm wide, apices rounded to acute, usually densely puberulent beneath. Receptacular paleae 11.5–15 mm long,  2–3 mm wide, with 2.5–5.5 mm long mucro. Ray florets 8–13, ligules usually orange, sometimes yellow, oval to oblong, 20–33 mm long, 6–17 mm wide. Disc florets 60–90, ca 10 mm long, pilose outside. Cypselas 4–6 (–8) mm long, black, brown or molted, appressed hairy. Pappus of hard, white scales with 2 ± equal, 3–5 mm long awns.