Helianthus annuus
L. Common SunflowerScabrous to hispid, erect annual or biennial herb 0.5–2 m high, taprooted. Leaves opposite below, alternate above, ovate to triangular, mostly 3–20 cm long and 2–12 cm wide, apex apiculate, base cordate or truncate, margins entire to serrate; petiole 1–10 cm long. Capitula 1–few, 3–20 cm diam., turned to one side or nodding; involucral bracts 3-seriate, ovate to lanceolate, 15–25 mm long, acuminate, scabrous, ciliate; receptacle scales 3-lobed, 8–12 mm long, membranous. Ray florets numerous, bright yellow, ligules mostly 2–3 cm long; disc florets numerous, brownish. Cypselas obovate, 5–10 mm long, broad-cuneate, 4-angled, black with grey streaks, finely appressed-pubescent; pappus of 2 minute, early-caducous scales. Flowers mostly Nov.–Jun.
MuM, Wim, VVP, MSB, RobP, MuF, GipP, Gold, EGU, HNF, Strz. Also naturalised WA, NT, SA, Qld, NSW. Native to North America. Widely cultivated for oil (extracted from cypselas) and as an ornamental; often escaping and weakly persisting along roadsides and in other disturbed sites.
Jeanes, J.A. (1999). Asteraceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 4, Cornaceae to Asteraceae, pp. 652–666. Inkata Press, Melbourne.
Spinning
