New England Trees

Bristly Locust
Robinia hispida

Plant Family: Fabaceae
Growth Form: Shrub up to 3 meters tall that spreads by rhizomes.
Leaves: Alternate, compound, with 7 – 13 oval to oblong leaflets that are 2 – 5 cm long.
Bark: Purple-brown with white lenticels, new twigs covered with short white hairs and longer red bristles.
Flowers: Showy, rose-colored to pale violet, with bristly flower stalks, in racemes up to 10 cm long, lacking fragrance; May to June.
Fruits: Flat, green or purple, bristly pods that ripen to brown, July to September.
Habitat: Dry woods, thickets, old fields, roadsides, human altered sites.
Range: Native to the southeastern United States, widely planted outside of that range, where it may escape the garden and naturalize. It is not considered invasive in New England.
Similar Species: Clammy Locust (R. viscosa), in the same genus, has similar flowers and growth form, but the twigs are covered by sticky glands, not the bristly red hairs of this species.
Comments: The genus is named for Jean Robin (1550 – 1629), French botanist and royal gardener.