2.
Ulmus alata
Michaux, Fl. Bor.-Amer. 1: 173. 1803.
Winged elm, wahoo
Ulmus americana
Linnaeus var.
alata
(Michaux) Spach
Trees , 10-18 m; crowns open. Bark light brown to gray with shallow ridges and plates. Wood hard. Branches: young and old-growth branches with opposite, prominent, regular corky wings; twigs reddish brown, pubescent to glabrous. Buds: apex acute; scales brown to rusty, slightly pubescent. Leaves: petiole ca. 2.5 mm, pubescent. Leaf blade lanceolate to oblanceolate, 3-6.9 × 0.6-3.2 cm, base somewhat cordate to oblique, margins doubly serrate, apex acute; surfaces abaxially with trichomes on veins, tufts of pubescence in axils of veins, adaxially glabrous to scabrous. Inflorescences short racemes, not pendulous, less than 2.5 cm; pedicel 2-7 mm, not fully expanded until fruiting stage. Flowers: calyx deeply lobed, symmetric, lobes 5; stamens 5; anthers red. Samaras gray-tan, often reddish tinged, lanceolate to oblong-elliptic, ca. 8 mm, narrowly winged, margins ciliate, cilia white, 1-2 mm. Seeds slightly thickened, not inflated. 2 n = 28.
Flowering late winter-early spring. Alluvial woods and deciduous woodlands, especially dry, acidic woodlands and glades, along fencerows, waste areas; planted as street trees; 0-600 m; Ala., Ark., Fla., Ga., Ill., Ind., Kans., Ky., La., Miss., Mo., N.C., Ohio, Okla., S.C., Tenn., Tex., Va.
Often planted as a shade tree in the southern United States, Ulmus alata is also cultivated outside North America.
The name Ulmus pumila was incorrectly applied to this species by Walter in 1788.
