purple-stem beggar-ticks, more...
[Bidens connata var. ambiversa Muhl. ex Willd., more]
Etymology: Bidens: derived from Latin bis, "twice," and dens, "tooth," hence meaning "2-toothed" and referring to the bristles on the achenes
Plants: erect, annual, 4"-80" tall, mostly smooth forb with purplish to green stems
Leaves: mostly on up to 1" long, winged stalk, toothed and often deeply cut but simple
Flowers: head with or without 1 1/2" rays, yellowish to orange disk 1/3"-1/2" wide, leafy bracts usually longer than the disk; inflorescence of a few stalked, erect heads; blooms Aug.-Oct.
Fruits: 2-4(6) barbed awns, the center one usually the shortest
Habitat: wet; disturbed areas