Bidens laevis is an annual herb to perennial, 25-100 cm tall, much like B. cernua, not nodding as much.
Leaves opposite, simple, long and narrow (lance-shaped), 4-20 cm long, 0.5-4.5 cm wide, stalkless, margins toothed sometimes lobed; sometimes nodding in fruit.
Flowers yellow, ray flowers about 8, 1.5-3 cm long, disk 1.5-2.8 cm wide, papery bracts among red-tipped disk flowers, basal bracts hardly leafy; flower heads erect; blooms and fruits Aug.Oct.
Fruit 1-seeded (achenes), 3-4 angled, with 2-4 barbed awns.
Wetland status: OBL.
Frequency in NYC: Very infrequent.
Habitat: Marshes, stream margins. Tolerant of brackish water.