blacklocusttreed-blog

[blacklocusttreed-blog]

Black Locust Tree

Black locust is native to North America, but not to Minnesota or the Upper Midwest. It is native to the Appalachian region and the Ozarks, where it is also considered a weed. It has been widely planted as an ornamental, for land reclamation, and for erosion control. It is also a major honey-producing plant in the eastern U.S. Black locust is spreading into new areas and is now a threat to other states which are outside of the historical range.

This tree is 40-80' tall at maturity, forming a trunk about 1½-3' across and an irregular crown with spreading to ascending branches. Trunk bark is variable, depending on the age of a tree; young trees have brown bark that is slightly rough and shallowly furrowed, while older trees have thick gray bark that is very rough and deeply furrowed with forking ridges. The bark of branches is gray to brown and more smooth, while twigs are brown to reddish brown, smooth, and glabrous with scattered white lenticels. Pairs of stout thorns about ¼-½" long occur along the twigs and branches near the axils of former leaves. Young shoots are light green and slightly pubescent. Alternate compound leaves about 6-14" long occur along the twigs and shoots; they are odd-pinnate with 7-19 leaflets. The stalks and leaflets of young compound leaves may be slightly pubescent, but they become glabrous with age; they are initially yellowish green. At maturity, individual leaflets are 1-2" long and ½-¾" across; they are medium green or blue-green, oblong or oblong-elliptic in shape, and smooth along their margins. Each leaflet has a tiny bristle-like tip, while at its base there is a short petiolule (basal stalklet) less than 1/8" (3 mm.) long.