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.

Broadly conical, deciduous. Vigorous growth and good form. Habitat beside rivers and will grow in very wet places. Tolerates salt winds better than the other alders. Good firewood crop to utilise wet ground. Timber durable under water.

Europe and N. Asia. Narrowly weeping, deciduous. Bark white, developing dark, rugged cracks at the base with age. Tough, vigorous pioneer species. Yellow autumn colour can be spoilt by birch rust in some seasons. Yields hard white timber.

Broadly conical, deciduous. Bark white, with horizontal marks retained to ground level into old age. Chalky white powder rubs off the bark. Bright yellow autumn colour. Vigorous and rust free.