Annuals, 50–200 cm . Stems single, branches virgate, usually glabrous, rarely tomentose. Leaves withered at flowering; basal blades oblanceolate to spatulate, runcinate, 3–10 cm, margins pinnately lobed (faces usually glabrous, rarely tomentose); cauline much reduced, bractlike. Heads borne singly or clustered along branches. Peduncles 3–10 mm, bracteate. Calyculi of appressed or reflexed bractlets. Involucres 6–8 mm. Florets 5–9. Cypselae light tan to dark brown, 2.2–3.6 mm, faces smooth to tuberculate, not grooved; pappi (falling) of 23–28, white bristles, wholly plumose. 2n = 16.
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