Honey locust is a medium-sized tree with a short, thorny trunk, thorny branches, and a loose, open crown.
Leaves are alternate, compound, 5–10 inches long, with 15–30 leaflets; leaflets ¾–2 inches long, broadest near the base to even throughout; margin entire or sometimes with very small, round teeth; upper surface shiny; lower surface paler, often hairy.
Bark is grayish brown to black, on older trees with grooves deep, narrow, separating into scaly ridges with sides or ends free and curved outward; often bearing heavy, simple or branching spines.
Twigs are greenish or reddish brown, shiny, stout, often zigzag, with solitary or branched spines that are rigid, sharp, straight, shiny, purplish brown, up to 12 inches long.
Flowers May–June; greenish white; male flowers in catkins, female flowers in clusters; found on separate trees or sometimes as a complete flower.
Fruit a dark brown, leathery pod, 6–18 inches long, narrow, flat, twisting at maturity; seeds 6–27, brown, oval, about ½ inch long.
Height: to 60 feet.
Occurs in bottomlands along streams and their valleys, also upland slopes and open or wooded pastures. It is a common invader of pastures and idle fields, and it is troublesome for farmers whose tractor tires the thorns puncture. It, and trees such as eastern red cedar, wild plum, and persimmon, are some of the first woody plants to grow in places where forests have been cut down, and their establishment is one of the first steps in that land reverting back to a woodland or forest community.
Cultivated thornless varieties of honey locust are popular in landscaping and along city streets — in autumn, the small leaflets blow away in the wind, and the little midveins make little mess.
Native Americans ate the fleshy sweet pulp of the young pods, and the pods and inner bark have been used medicinally in the past.
The seeds and pulpy pods provide winter food for rabbits, squirrels, and deer.
The flowers are reportedly a good bee food.
Honey locust is a top food plant for caterpillars of the honey locust moth, bisected honey locust moth, silver-spotted skipper, moon-lined moth, and the orange wing.
Honey locust is a “pioneer” or early colonizing species, one of the first kinds of trees to become established in disturbed landscapes such as old fields and pastures that are reverting back to forest.
There are no sharp dividing lines between trees, shrubs, and woody vines, or even between woody and nonwoody plants. “Wood” is a type of tissue made of cellulose and lignin that many plants develop as they mature — whether they are “woody” or not. Trees are woody plants over 13 feet tall with a single trunk. Shrubs are less than 13 feet tall, with multiple stems. Vines require support or else sprawl over the ground.