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Nodding Beggarsticks (Bidens cernua)

• Family: Aster (Asteraceae)
• Flowering: August-October.
• Field Marks: This Bidens differs from other species with showy rays by its undivided simple leaves, its nodding heads, and its somewhat winged fruits.
• Habitat: Around ponds and lakes, along streams, swamps, wet meadows, roadside ditches, marshes, bogs.
• Habit: Annual herbs with a taproot.
• Stems: Erect or sometimes growing along the ground and rooting at the nodes, smooth or hairy, often branched, up to 5 feet tall.
• Leaves: Opposite, simple, linear to lanceolate, pointed at the tip, more or less rounded at the sessile or slightly clasping base, with or without teeth, smooth or hairy, up to 6 inches long, up to 1 1/2 inches wide.
• Flowers: Many crowded together into a head, the outer yellow and flat, the inner yellow and tubular, forming a disk, with several heads per plant, each head subtended by 5-8 narrow, leafy bracts.
• Sepals: 0.
• Petals: Some yellow, united to form flat rays up to 2/3 inch long and up to 1/3 inch wide, others yellow, 5-lobed, united below into a tube.
• Stamens: 5.
• Pistils: Ovary inferior.
• Fruits: Achenes mostly flat, broadest at top, tapering to a narrow base, green-black, barbed along the edge, up to 1/3 inch long, about 1/10 inch broad, with four stiff barbed awns at the upper end.
• Notes: The fruits of this species are eaten by ducks.