Trees to 40 m tall, 1--1.5 m d.b.h, glabrous. Branchlets grayish brown; bud ca. 1 cm. Stipule narrowly oblong, ca. 1 cm. Petiole 2--4 cm; leaf blade broadly ovate, 7--16 × 4--12 cm, papery, abaxially paler, base cordate to rarely truncate rounded, margin serrulate, apex acuminate; palmate veins 5--7. Inflorescences 6--15 cm, short pedunculate, 80--125-flowered but some aborted by anthesis. Floral subtending bracts 0.3--0.5 × 0.4--0.7 mm. Flowers yellowish green, sessile, 1--2 mm in diam. Sepals ovate-orbicular, 1--2 mm, margin entire, apex rounded. Stamens exserted; filaments subterete to slightly flattened, 1.5--3 mm; anthers 0.4--0.8 mm, locules lateral, each theca dehiscent by a lateral slit, connective truncate-rounded at apex. Carpels ca. 1.5 mm at anthesis. Styles at first erect and connivent, becoming recurved at anthesis, subulate; stigma along the ventral surface of the style. Fruit brown, follicles 2.5--5 mm, dehiscence loculicidal, persistent style pointing toward follicle base due to expansion of follicle ventral side. Seeds 4--6 per follicle, spindle-shaped, 2--3 mm, compressed, short winged at each end. Fl. Apr--Jul, fr. Jul--Oct. 2n = 48