Maple

Trees up to 15 m tall, andromonoecious. Branchlets purplish-green, glabrous, with elliptic or oblong lenticels; winter buds ovoid, scales yellowish pubescent outside. Leaves deciduous; petiole pale green or purplish-green, 4-5 cm, glabrous; leaf blade (7-)8-15 × 9-22 cm, membranous, abaxially pubescent on veins when young or nearly glabrous, glabrous when mature except for tufts of barbed hairs at vein axils, adaxially glabrous, primary veins 7, secondary veins 18 or 19 pairs, base cordate, rounded, cuneate, or truncate, (5 or)7(or 9)-lobed, sinuses to 1/2 width of the blade; lobes lanceolate or ovate-oblong, 1-1.5 cm, margin remotely or doubly serrulate, apex acuminate.

Inflorescence terminal, paniculate, 4-6 cm, glabrous. Sepals 5, ovate. Petals 5, yellow-green. Stamens 8, glabrous. Disk pubescent, extrastaminal. Ovary densely white pilose. Fruit yellowish when mature; nutlets convex, ca. 5 mm in diam.; wing falcate, including nutlet 2.3-2.8 cm × ca. 8 mm, wings spreading nearly horizontally. Fl. May, fr. Sep. 2n = 26.