It is a medium-sized
deciduous tree growing to 20–30 m tall with a broad, rounded crown. The
leaves are opposite,
palmately lobed with 5-7 lobes, 6–15 cm across. The leaf stems bleed a milky
latex when broken. The
flowers are in
corymbs of 15-30 together, yellow-green with five petals 3–4 mm long; flowering occurs in early spring. The
fruit is a double
samara with two winged
seeds, the seeds are disc-shaped, strongly flattened, 6–11 mm across and 2–3 mm thick. The wings are 2.5–3 cm long, widely spread, approaching a 180° angle. The bark is greenish-grey, smooth in young trees, becoming shallowly grooved when mature. == Taxonomy ==