Japanese sunflower
Tithonia diversifolia

Perennial herb, 2.5–5 m high; stem strongly striate, hairy at first then glabrescent.

Leaves ovate in outline, 7–33 cm long, 7–22 cm wide, unlobed to 3–5-lobed, margins toothed, apex acuminate, base decurrent on petiole; petiole to 6 cm long, auriculate at base.

Peduncles up to 24 cm long; heads 3–5 cm diam.; receptacle scales 1–2 cm long; involucral bracts graduated, oblong to ovate, 3- or 4-seriate. Ligules yellow, linear, 5–7 cm long, apex 3-toothed; ray achenes in 1 row, white to yellow. Disc achenes black or mottled, 4-angled, 5–6 mm long; pappus of fused scales and 2 ± equal awns, 5 mm long.