USGS - science for a changing world

Northern Prairie Wildlife Research Center

  Home About NPWRC Our Science Staff Employment Contacts Common Questions About the Site

Aquatic and Wetland Vascular Plants of the Northern Great Plains

49. Asteraceae, the Aster Family

3. Bidens L. -- Beggarticks

2. Bidens cernua L. -- Nodding beggarticks


Small to large, often bushy annual 1-12 dm tall; stem glabrous or with spreading hairs. Leaves simple, linear-lanceolate to ovate-lanceolate, 3-18 cm long, 0.5-4.5 cm wide, acuminate, shallowly to coarsely toothed and usually scabrous on the margin, sessile and usually clasping at the base. Heads discoid or radiate, hemispheric, 1.5-3 cm across, usually nodding after flowering; outer involucral bracts 4-8, linear-lanceolate, unequal, often exceeding the disk; rays, when present, 6-8, yellow, to 1.5 cm long. Achenes with 4 retrorsely barbed awns, the body often purplish with pale, thickened margins, 5-7 mm long, retrorsely barbed on the margins. Aug--Oct. Shores, stream banks, marshes, ditches, wet meadows and other wet places; common; (N.B. to B.C., s to NC, OK, NM and CA; also widespread in the Old World).
GIF- Distribution Map

Map key


Previous Section -- Bidens bipinnata L. -- Spanish needles
Return to Family -- Asteraceae - The Aster Family
Next Section -- Bidens comosa (A. Gray) Wieg.

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.npwrc.usgs.gov/resource/plants/vascplnt/species/bcer.htm
Page Contact Information: Webmaster
Page Last Modified: Saturday, 02-Feb-2013 06:40:16 EST
Menlo Park, CA [caww55]