Albania and Nth Greece. Broadly conical, deciduous. Large palmate compound leaves produce a dense shade. Large creamy white flowers, then prickly oval fruits, enclosing polished conkers prized by schoolboys in the UK. Best in fertile soils.

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.

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.