*Bidens tripartita L.

Leaves divided pinnatisectly into 3 segments; terminal segment 6–8 cm long, 2 cm wide; lateral segments half as large; all coarsely toothed. Herb up to 1 m high, with a single erect stem with few or no branches. Heads terminal and axillary. Involucral bracts 1–2 cm diam. Ray yellow. Cypselas 6–8 mm long. Pappus awns 2–4 mm long, finely barbed. Coast. Near habitation. Introd. from America. Fl. autumn–winter. Burr Marigold