Black Locust - Yellow Locust
Robinia pseudoacacia - (Linnaeus)
Fabaceae (Pea) Family

Plant is an upright tree. Height may be 50-80 feet when left undisturbed, with a trunk diameter of 1 - 2 feet. Its preferred habitat is moist to dry sandy and rocky soils, especially in old fields and open areas of woodlands. Distribution is throughout the Escambia region.

The leaves are typical of shrub/trees in the Legume family; including Indigo, Mimosa, Mesquite and Acacia; pinnately compound, six to twelve inches long with seven to nineteen leaf segments along a central leaf stalk. Each leaflet is equipped with a bristle tip and the segments fold at night. The leaf is dark green above, pale and usually hairless beneath. The new growth leaves have downy hair on both sides.

Flowers are also typical of the legumes; pea-shaped with 5 unequal white petals, the largest being somewhat yellow near the base. Clusters hang from the tree like wisteria and are very fragrant; attracting numerous pollinators. Flowers occur in the spring.

Fruit is a long pod which matures in late summer or autumn and remains attached into winter. The pods split, releasing dark brown bean-like seeds that are slightly flattened.

Black Locust is widely planted as an ornamental and shelter belt, as well as for erosion control; especially on lands that have been strip-mined. It is fast growing and puts down a wide root system. Therein lies its greatest value at the moment.  Spreading rapidly could present a problem as well if placed too close to a dwelling as it will clog water and field lines.

Virginia Indians made bows of the pliant wood and it is said whenever the tribe moved it took seedlings with them for starting a new stand of trees, thus it was widely cultivated. Colonists found the wood ideal for house corner posts. Originally found in the Appalachian region from Pennsylvania south to Georgia and west to Arkansas, Indiana and Illinois, it was then planted throughout the eastern United States.  When the tree stands reached seashore it was found that its durability was ideal for wooden pegs, ship timbers, insulator pins, and piles.  It is also associated with those plants having nitrogen fixing bacteria.  The Ship mast Locust (R. rectissima) is a natural variety of this tree.

Previous Page

Return to Index

Next Page