A thorny, multi-trunked shrub, or a medium-sized tree to 40 feet tall and one or more leaning, crooked trunks 18" to 24" in diameter, with a spreading, open, irregular, crown of drooping foliage.

One of the most common species in Texas, occurring statewide except for East Texas where it occurs rarely, on salty soils. Mesquite is quite invasive in cattle pastures and open, unmaintained fields.

Alternate, compound, bi-pinnate, with the two pinnae attached to a long petiole; each pinna consists of 10 to 20 leaflets attached to a central rachis, 8" to 10" long. The leaflets are linear, 2" long by 0.25" wide, smooth, medium green, often blunt or rounded at the tips.

Long, cylindrical spikes, 2" to 4" long, of small, yellow flowers appear from the leaf axils in spring or early summer.

A reddish-brown or purplish pod about 4" to 9" long, like a pea pod but constricted slightly between the 10 to 20 seeds, which are enclosed in a thick, sweet pulp; used by native peoples as food and eagerly sought by wildlife and livestock.

Twigs and branches armed with stout, straight thorns up to 2" long. Bark is thin and brown or gray at first, breaking into a dark, rough, scaly surface on branches, and then into dark brown or black ridges and furrows on the trunk.

Wood is heavy, hard, and dark brown in color, with lighter sapwood, and is used for fuelwood, barbeque wood, fenceposts, flooring, furniture, and paneling. Flowers make an excellent honey, and the seeds are sometimes used as livestock forage during droughts. Also used as a drought-tolerant landscape tree.

Western honey mesquite (Prosopis torreyana) has smaller leaflets and occurs in West Texas only.

Known as a "phreatophyte" because of the ability of its very large and spreading root system to draw scarce water from grasslands, fields, and streams, it is considered a weed species by farmers and ranchers. Leaf-out in springtime is a sign to local farmers that the last frost has passed.