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Black locust

Robinia pseudoacacia L.

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Black locust leaves
Black locust bark
Black locust leaf
Black locust fruit
Black locust fruit
Black locust fruit
Black locust
Black locust leaves
Black locust
Black locust inflorescence
Black locust fruit

Morphology

Trunk
Trunks erect, 1 to 2 feet in diameter; usually low-branching; crown rounded or irregular; bark reddish brown to gray, deeply furrowed.
Twigs
Slender, rigid, gray or reddish-brown, often zigzag, with pairs of short, stout spines at nodes; leaf scars triangular.
Leaves
Alternate, stalked, odd-pinnately compound, 4 to 10 inches long; leaflets 7-27, elliptic to oblong-ovate, 3/4 to 2 inches long, 1/2 to 1 inch wide, bluish green above, paler green below, nearly glabrous; margins entire; tips rounded.
Flowers
Showy, fragrant, short-stalked; calyces bell-shaped, 5-toothed, finely hairy; corollas papilionaceous, white; banner 1/2 to 1 inch long, erect or bent backward, greenish yellow patch at base; stamens 10.
Fruit
Pods, 2 to 4 inches long, about 1/2 inch wide, straight, smooth, flat, brown, persist through winter; seeds 3-12, kidney-shaped, hard, dark-brown.

Ecology

Habitat
Dry or moist roadsides, open woods, shelterbelts, pastures, thickets, and stream valleys.
Distribution
Throughout Kansas.

Additional Notes

Comments

Often planted by early settlers and escaped into the wild. The leaflets fold together at night. Black locust is drought tolerant but susceptible to insect borers and fungal diseases. Its wood is hard and durable. Robina honors Jean Robin, 1550-1629, French botanist.

Quick Facts
Plant Type
Tree
Family
Fabaceae - Bean Family
Height
Up to 50 feet
Last Updated
2007-10-20
Flowering Period
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Blooms: May, June