Leaf: alternate, pinnately compound; 6-12" (15-30 cm) long. 7-19 leaflets 1-1 3/4" (2.5-4.5 cm) long, 1/2-3/4" (12-19 mm) wide; paired (except at end); elliptical; with tiny bristle tip; without teeth; hairy when young; drooping and folding at night. Dark blue-green above, pale and usually hairless beneath.
Flower: 3/4" (19 mm) long; pea-shaped; with 5 unequal white petals, the largest yellow near base; very fragrant; in showy drooping clusters 4-8" (10-20 cm) long at base of leaves; in late spring.
Fruit: 2-4" (5-10 cm) long; narrowly oblong flat pod; dark brown, maturing in autumn, remaining attached into winter, splitting open; 3-14 dark brown flattened beanlike seeds.
Twig: dark brown, with stout paired spines 1/4-1/2" (6-12 mm) long at nodes.
Bark: light gray; thick deeply furrowed into long rough forking ridges.
Form: Medium-sized, spiny tree with a forking, often crooked and angled trunk and irregular, open crown of upright branches.
Habitat: Woodlands, thickets and roadsides.
Range: Pennsylvania across to Oklahoma, east to Georgia; often planted in other regions of the eastern United States.
Location: Warren Street, on west edge of Bunker Hill.
Latitude: 39o02.55N
Longitude: 089o57.56W
Black Locust is used for ornament and shelterbelts, and for erosion control. Virginia Indians made bows of the wood and apparently planted the trees eastward. Post made from this durable wood served as cornerposts for the colonists' first homes.
© Community Unit School District #8, Bunker Hill
504 E. Warren, Bunker Hill, IL 62014
References:
Little, Elbert L. Field Guide to Trees: Eastern Region. New York, NY: Alfred A. Knopf Inc., 1980.
Mohlenbrock, Robert H. Forest Trees of Illinois. Springfield, IL: 1992