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Annuals.  Stems are often branching from near plant base.  Typical height is 3 to 4+ feet.

Inflorescences consist of a few flower heads located at the summit of the stem, at ends of branches in flat- or round-topped clusters, or in leaf axils. 

Flower heads are discoid, erect (not nodding) (not nodding).  Ray florets are rarely present.  Disc florets are bisexual and fertile, 20-60+ per head; the corollas are yellow-orange, readily falling as fruits mature.  Involucral bracts are in two series: an inner series - which are short, yellowish and petal-like; and an outer series - of 5-10 longer, narrower, green, leaf-like, with ciliate margins.

Basal leaves are absent at flowering.    Primary stem leaves are opposite, borne on petioles, divided into 3-5 lanceolate or lance-ovate leaflets, and coarsely toothed.

Cypselae are dark brown, compressed, flat or concave at the summit, narrowed toward the base, the faces often dotted with minute tubercules.  The pappus is of 2 minutely barbed awns, 2-5 mm long.

Plants of shorelines, wet meadows as well as drier, disturbed sites (our most common species; becoming weedy).  Flowers late August to late September.  Native..

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Similar species:  Bidens discoidea.

 

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