Erect, usually branched annual herb to c. 2 m high; stems hispid, unarmed, purplish. Leaves broad-ovate to triangular in outline, mostly 4–15 cm long and wide, 3- or 5-lobed, dark green, dull and scabrous above, paler and scabrous beneath, prominently 3-veined, lobe apices acute to subacute, base cordate to truncate, margins coarsely and irregularly toothed; petiole 2–12 cm long. Male capitula 0–7, 5–8 mm diam.; involucral bracts ovate, 1–3 mm long; florets c. as long as involucre, pubescent. Female capitula 1–12 in axils below males; fruiting involucre ellipsoid, 4–7 mm diam., 12–20 mm long, pubescent with wholly or predominantly eglandular hairs; hooked spines 2–3 mm long, pubescent in lower half, dark brown; beaks broad-based, 3–5 mm long, divergent, more or less straight, the tips straight or inflexed, but not strongly hooked. Cypselas 1–1.5 cm long. Flowers Dec.–Mar.
MuM, Wim, VVP, VRiv, MSB, RobP, MuF, Gold, CVU, NIS, EGU, HSF. Also naturalized WA, NT, SA, Qld, NSW. Native to North America and the Caribbean. Scattered across northern Victoria from Mildura to Corryong, on river flats, in pastures and irrigated land.
