Bidens L.

5 species naturalized Aust.; all states and territories except Tas.

Herbs with opposite mostly compound or pinnatisect leaves. Heads on terminal peduncles. Involucral bracts few, in 2–3 rows. Ray florets sterile, ligulate or sometimes absent. Disc florets tubular, bisexual. Cypselas slender, 4-angled. Pappus of 2–4 rigid barbellate awns.