Annual or biennial. Roots tap and fibrous. Stem erect, usually simple, finely grooved or ribbed, glabrous, (15)-20-60-(180) cm tall. Lvs firm-textured, ± shiny, usually green or rarely glaucous above, paler to ± glaucous beneath, glabrous, lanceolate to oblanceolate or obovate; margins sinuate-dentate with prickly-spinose teeth. Rosette and lower stem lvs tapering to expanded auriculate base, (4)-10-20-(40) × (1.5)-3-6-(15) cm, pinnatifid to c. 1/2 way to midrib or rarely not lobed; lobes recurved to spreading, triangular to lanceolate. Upper lvs pinnatifid or not lobed, narrowly triangular to subulate, with rounded amplexicaul auricles at base. Infl. cymose to umbellate; capitula few to many. Involucre 10-15 mm long, turbinate to cylindric; bracts imbricate, reflexed at fruiting, glabrous or rarely with tangled white short branching hairs and sparse long pale glandular hairs. Receptacle glabrous. Florets 11/2× length of involucre; corolla tube > ligule; ligules spreading, yellow. Achenes elliptic, pale brown, strongly flattened, 2.5-3 × 1-1.6 mm, 3-ribbed on each face, winged; spaces between ribs smooth; ribs and edges of wings smooth or finely scabrid. Pappus fine, white, c. = involucre.