Annual herbs, (10–) 50–100 cm tall. Stems robust, terete, simple or usually branched from the base, puberulent or sparsely tomentose. Leaves often with axillary, abortive buds, petiole 1–3 cm long, densely white spreading villous; median leaves ovate, elliptic, oblong or ovoid, 3–8 cm long, 2–5 cm wide; upper leaves gradually smaller, oblong, ca 1 cm long, ca 0.6 cm wide, sparsely puberulent with gland dots on either side, basally obscurely 3 or 5, veined, base obtuse or broadly cuneate, margins crenate to serrate, apex acute. Involucre campanulate or hemispheric, ca 5 mm in diameter; phyllaries biseriate, oblong or lanceolate–oblong, 3–5 mm long, ca 1 mm wide, acute – acuminate,  glabrous, margins lacerate. Capitula (4–) 5–14 (–15) across, on 0.5 – 1.5 cm long, puberulent peduncles, in dense terminal corymbs. Florets many. Corolla 1.5–2.5 mm wide, glabrous or apically puberulent, ligule purplish, 5–lobed. Cypselas black, blue, mauve, rarely white, 5–angled, 1.2–1.7 mm long, sparsely white setuliferous on the ribs. Pappus scales 5, usually flattened at base, rarely awned, awns 1.5–3 mm long.