East USA. Broadly spreading, deciduous. Bark pink-grey, peeling in thin shaggy flakes. Will grow in swampy and damp sites. Strong root system for binding wet slips.

N.E.USA and Canada. Broadly conical, deciduous. White mature bark peeling in thin sheets. Young bark is shiny brown with pale brown lenticels. Leaves are heart shaped dotted with resin glands, yellow autumn colour. Occurs on moist soils at higher altitude.

Long weeping branches. The bark remains white to the ground longer than the usual form. Tough vigorous pioneering species. Yellow autumn colour can be spoilt by birch rust in some seasons. Yields a hard white timber.

Caucasus mountains of Georgia. Broadly conical, deciduous. Bark silvery grey, rare in NZ.