Yellow Crownbeard

Plants 80–200+ cm (perennating bases ± erect, internodes winged). Leaves all or mostly opposite (distal sometimes alternate); blades ± ovate or lance-deltate to lanceolate, 6–12(–16+) × 3–6(–10+) cm, bases ± cuneate, margins coarsely toothed to subentire, apices usually acute to attenuate, sometimes rounded, faces scabrellous. Heads 20–100+ in corymbiform-paniculiform arrays. Involucres campanulate to turbinate, 3–5+ mm diam. Phyllaries 8–12+ in 2 series, ± erect, spatulate to oblanceolate, 3–7+ mm. Ray florets (0–)1–3(–5); laminae 10–15(–20+) mm. Disc florets 8–15+; corollas yellow. Cypselae dark brown to black, oblanceolate, 5 mm, faces strigose; pappi 3–4 mm. 2n = 34.

Siegesbeckia occidentalis Linnaeus, Sp. Pl. 2: 900. 1753