Desmodium canadense showy tick-trefoil Fabaceae DECA; Bx, pb, vc; R, k;

Desmodium canadense plant in bloom. By Donald Cameron. Copyright © 2018 Donald Cameron. New England Wild Flower Society. gobotany.newenglandwild.org

Desmodium canadense plant in bloom. By Donald Cameron. Copyright © 2018 Donald Cameron. New England Wild Flower Society. gobotany.newenglandwild.org (Accessed 2/2018).

Desmodium canadense is a perennial herb, to 2 m tall, one to several stems, from a brown root, aerial stem branched above, finely hairy above; stipules 0.5-0.9 cm long. 

Desmodium canadense plant in bloom. Arthur Haines. New England Wild Flower Society. gobotany.newenglandwild.org

Desmodium canadense plant in bloom. Arthur Haines. New England Wild Flower Society. gobotany.newenglandwild.org

Leaves alternate, 3-parted, leaf stalk 0.2-2 cm long, stipules of leaflets 0.2-0.4 cm long, leaflet stalks (petiolules) 0.2-0.3 cm long, central leaflet 5-10 cm long, 2-3.8 cm wide, elliptic to egg-shaped, hairy below, dull green, margins entire, stalks 1-2 cm, hairy, much shorter than terminal leaflet. 

Desmodium canadense flowers and fruit. By Glen Mittelhauser. Copyright © 2018 Glen Mittelhauser. New England Wild Flower Society. gobotany.newenglandwild.org

Desmodium canadense flowers and fruit. By Glen Mittelhauser. Copyright © 2018 Glen Mittelhauser. New England Wild Flower Society. gobotany.newenglandwild.org (Accessed 2/2018).

Flowers rose-purple, becoming blue, 0.8-1.3 cm long, bilaterally symmetrical, bean-flower shaped, calyx bilaterally symmetrical; inflorescence a dense raceme at top of stem ; blooms July-Aug. 

Desmodium canadense fruit in winter. By Frank Bramley. Copyright © 2018 New England Wild Flower Society. gobotany.newenglandwild.org

Desmodium canadense fruit in winter. By Frank Bramley. Copyright © 2018 New England Wild Flower Society. gobotany.newenglandwild.org (Accessed 2/2018).

Fruit dry, jointed between seeds into 1-5 segments, upper suture slightly curved, lower suture of each segment rounded, surface densely hooked-hair y, segments breaking at joints between seeds. Seeds dispersed by sticking to fur or clothing (Matlack 1994), eaten by some birds and small mammals (Martin et al. 1951). 

Wetland status: FAC. 

Frequency in NYC: Very infrequent. 

Origin: Native. 

Habitat: Open woods, moist soil, river banks.