Annual, 8-12 dm tall, glabrous throughout or with a few inconspicuous hairs on the peduncles and phyllaries. Stems single, striate, the proximal third 10-1 5 mm in diameter, narrower distally, hollow, with a conspicuous reddish subepidermal layer when freshly cut; arising from a short, thin taproot surrounded by abundant, thin and sparingly branched fibrous roots. Basal and proximal cauline leaves with blades ovate, mostly 12-24 cm long and 8-12 cm wide, margins wavy, with a few scattered minute denticles, midvein prominent and lateral veins less conspicuous in dried specimens, tapering or gently contracted to a distinct petiole, ca. 2/3 the length of the blade. Middle cauline leaves with blades nearly as large as the basal leaves, ovate to broadly lanceolate, sessile and clasping . Distal cauline leaves lanceolate to linear-lanceolate, 6-14 cm long, sessile, the distal most further reduced and bractlike. Capitulescences terminal or arising from the axils of the upper leaves;fundamentally corymbiform cymes of 20-40 capitula, or a close cluster of corymbiform cymules. Involucres cylindrical or turbinate to weakly cam- panulate, each subtended by a weakly defined calyculus of 2-7 linear bracteoles, 1-3 mm long, margins hairy. Phyllaries mostly 1 3, 8 mm long, green with hyaline margins, abaxial surfaces with short hairs distally, the apex with a minute tuft of hyaline hairs. Corollas yellow. Ray florets mostly 8, pistillate; corollas ca. 1 1 mm long, tubes 4 mm and laminae ca. 7 mm long, 2.5 mm wide. bisexual;corollas 7( 1 0) mm long, tube and limb (including lobes) of about equal length, corolla lobes triangular, 0.5 mm long . Cypselae not seen, oldest ovaries wrinkled, empty, 1 -3 mm long, pubescent through- out. Pappus of abundant white, minutely barbellate bristles in a single series, 6-7 mm long. Chromosome number unknown.