Shrub 1 - 2 m tall Leaves: alternate, stalked (4 - 10 mm), 3 - 8 cm long, 1.2 - 3.3 cm wide, lance-shaped to elliptic with a wedge-shaped to rounded base and a short-pointed to blunt tip, finely toothed, hairless or nearly so beneath, with four to ten vein pairs slightly curving toward the leaf tip. Flowers: solitary or in small clusters borne in leaf axils, greenish yellow, to 3 mm wide, four-petaled. Fruit: fleshy with two center seeds (drupe), black with a thin whitish coating, containing shiny light brown seeds 6 mm long and grooved along one side. Twigs: slender, reddish brown and hairless or with few hairs when young, becoming gray, sometimes peeling on older growth. Form: erect, widely branched, rarely forming thickets.
Similar species: The typical variety of Rhamnus lanceolata has hairy twigs and leaves.
Flowering: April to June
Habitat and ecology: This species is one of rarest shrubs of the Chicago area and grows in calcareous fens.
Occurence in the Chicago region: native
Notes: The fruit is eaten by birds, while deer eat the twigs in winter. Song- and game-birds use the low branches and numerous small branchlets of this species as protection. It is occasionally planted as an ornamental shrub.
Etymology: Rhamnus is the ancient Greek name for buckthorn. Lanceolata means lance-shaped, referring to the leaves. Glabrata means "without hairs,"referring to the leaves and twigs.