A deciduous tree probably 60 ft high ultimately. Leaves three; four; or five-lobed, 3 to 7 in. (sometimes as much as 10 in.) wide; two-thirds as long, dark glossy green above, with tufts of brown hairs in the axils of the veins beneath; lobes broadly triangular, blunt-pointed, margins nearly always entire. Flowers yellow, in corymbs. Fruit glabrous; the keys 11⁄2 to 13⁄4 in. long, spreading at a broad angle.
A hybrid, believed to have originated from A. platanoides and A. lobelii; introduced from the Zoeschen nursery to Kew in 1887. It was first sent out under the second synonym given above. The leaf-stalk exudes a milky sap when broken.