Bidens frondosa devil’s beggar ticks  Asteraceae BIFR; Bx, br, bz, sd, up, wv (Yost et al. 1991); Q, a, cu; i; K, p; R, bd, bk, c, fk, gb, is, js, lp, sv, ty;

  

Bidens frondosa (beggar ticks) plant in bloom. MBGargiullo. roadside, Falmouth, MA. 9/14/2017

Bidens frondosa (beggar ticks) plant in bloom. MBGargiullo. roadside, Falmouth, MA. 9/14/2017

Bidens frondosa is an annual, 20 cm to 1.2 m tall, generally hairless, stem often purple, especially if water stressed. 

Leaves opposite, pinnately compound, stalks (petioles) 1-6 cm long, leaflets 3-5, to 10 cm long, 3 cm wide, narrow, toothed, the terminal leaflet stalked. 

Bidens frondosa.nova Scotia Wild Flora Society.nswildflorw.ca

Bidens frondosa.nova Scotia Wild Flora Society.nswildflorw.ca (12/2014).

Flowers yellow, heads small, rounded, rays few if any, disk orange, to 1 cm wide, stamens black, longer than disk flowers, outer bracts 5-10, (usually 8) green, leaf-like, margins hairy-fringed, longer than disk, inner bracts flat, scale-like, blooming and fruiting June-Oct. 

Bidens frondosa fruit. 2011 © Peter M. Dzuik. Minnesota Wildflowers. minnesotawildflowers.info

Bidens frondosa fruit. 2011 © Peter M. Dzuik. Minnesota Wildflowers. minnesotawildflowers.info (Accessed 11/2017).

Fruit dry 1-seeded achenes, flat, 0.5-1.0 cm long, dark with 2 barbed awns. Seeds eaten by birds, plants eaten by rabbits (Martin et al. 1951). 

Wetland status: FACW. 

Frequency in NYC: Occasional. 

Origin: Native. 

Habitat: Wet, open areas, edges, disturbed soil, pH 5.2-7.2; shade tolerance moderate (USDA 2006).