A tree up to 15 ft or more high, and perhaps the most formidably armed of all thorns, the spines being sometimes 4 or 5 in. long, and very abundant; young shoots reddish brown, glabrous. Leaves roundish oval or obovate, 2 to 4 in. long, 11⁄2 to 3 in. wide; tapered more or less at the base, pointed at the apex, the upper part usually more or less lobed; sharply toothed; dark green, leathery, glabrous above except when young; remaining downy beneath, although finally only on the parallel veins (of which there are six or seven pairs) and the midrib; stalk 1⁄4 to 3⁄4 in. long. Flowers white, 3⁄4 in. across, produced in May and June in corymbs 2 or 3 in. wide; flower-stalk either downy or not; calyx-lobes narrow, downy inside, glandular-toothed; stamens eight to ten, anthers yellow. Fruit globose, bright crimson, 1⁄3 to 1⁄2 in. diameter.
Native of eastern N. America; introduced in 1819. It is one of the most remarkable of all thorns in the extraordinary number and size of its thorns, even larger than in C. crus-galli. It is also one of the handsomest in fruit, a good grower, and very hardy. It differs from both C. tomentosa and C. succulenta in having not more than ten stamens, and yellow anthers. All three species are characterised by a longitudinal cavity on the inner side of the nutlets.