Corsica, central and S. Italy. Broadly conical, deciduous, fast growing, roots penetrate deeply. Popular for horticultural shelterbelts, trims well into a narrow tall hedge. Sheds some leaves in drought conditions. Used as a nurse crop with oak and redwood providing mycorrhiza, nitrogen and side shade to reduce epicormic regrowth on pruned final crop trees.

West North America. Broadly conical deciduous. Vigorous growth on hillsides as well as stream sides. Produces good hardwood timber for furniture and panelling. Planted for shelter. Red winter buds identify this alder.

Northern North America. Broadly conical, deciduous. Bark white, peeling in thin layers, pale pinkish-orange when freshly exposed. Leaves relatively large, bright yellow in autumn. Yields hard white timber.

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.