Quercus × riparia Laughlin

Tree to 20 m tall, 40 cm dbh. Bark thin, dark grey-brown, obscurely ridged. Young shoots glabrous, angled. Leaves deciduous, broadly elliptic to obovate, to 20 × 15 cm, with usually 4 lobes on each side. Lowest lobes pointed, entire, increasing in size toward the leaf apex, where they are broad and sometimes shallowly lobed with several bristle-tipped teeth, the sinuses reaching up to halfway to the midrib. They are red when young, becoming yellow-green above, paler beneath and glabrous on both sides when mature except for small tufts of rust-coloured hairs in the vein axils. Petiole to 5.6 cm long, glabrous. Fruits borne singly or in pairs on a peduncle to 12 mm long, cupule bowl-shaped, to 14 × 22 mm, acorns to about 2 cm long, ½ enclosed in the cup and ripening the second year. (Laughlin 1963).

Distribution  Canada Ontario United States Missouri

USDA Hardiness Zone 4

RHS Hardiness Rating H6