旱榆 han yu

Trees or shrubs, to 18 m, deciduous. Bark ± longitudinally fissured. Branchlets glabrous or pubescent, unwinged and without a corky layer; second year branchlets grayish yellow, yellowish gray, or yellowish brown. Winter buds brown, ovoid-orbicular to ± globose; inner scales pubescent or puberulent. Petiole 3-8 mm, pubescent; leaf blade elliptic, rhombic-ovate, narrowly ovate, or elliptic-lanceolate, 2.5-5 × 1-3 cm, both surfaces pubescent or subglabrous and often with tufts of hairs in forkings of secondary veins but never in vein axils, base asymmetrically acute to obliquely truncate, margin obtusely and regularly simply serrate or ± doubly serrate, apex weakly to strongly acuminate; secondary veins 6-12(-14) on each side of midvein. Inflorescences fascicled cymes on second year branchlets, 3-5-flowered. Flowers from mixed buds or floral buds, scattered at base or near base of branchlets. Perianth campanulate, ca. 4-lobed, glabrous or lobe margins ciliate. Samaras tan, elliptic, broadly elliptic, or obovate, 2-2.5 × 1.5-2 cm, glabrous or pubescent; stalk 2-4 mm, pubescent; wings thick; perianth persistent. Seed at center or toward apex of samara. Fl. and fr. Mar-May.

* Along rivers, mountain slopes; 2000-2600 m. Gansu, Hebei, Henan, Liaoning, Nei Mongol, Ningxia, E Qinghai, Shaanxi, Shandong, Shanxi.