|'Crispa' is an upright, narrow, slow-growing tree with thin, greenish-brown, shoots. Leaves are strikingly twisted, forming circular shapes, narrow and lance-shaped, light green, up to 4 in. long. Narrow, silvery-green catkins on males, to 2 in. long, with yellow anthers, on females to 1 in. long. A beautiful specimen by water, but don't plant this tree anywhere near a septic system or its lines or you and the Roto-Rooter man will know each other on a first name basis. Native to N. China.