European Black Alder, a native of Europe, northern Africa, and western Asia, was introduced to North America long ago and has escaped from cultivation, and it is sometimes seen along bodies of water, where it may successfully self-sow and form pure stands. Today, it is grown as a shade tree in urban areas, or at wet sites (ponds, creeks, drainage ditches, etc.) where it thrives and provides both erosion control and ornamental appeal.
Its leaves easily flutter in the breeze, and forms are available that are cutleaf (leaves having deep sinuses that give them a much finer texture). In addition, columnar forms exist for narrow spaces.
In late winter, its emergent pendulous catkins sway in the breeze, providing early ornamental appeal. Trees found in the open may reach 60 feet tall by 25 feet wide. As a member of the Birch Family, it is related to the Birches, Hornbeams, Filberts, and Hophornbeams, in addition to other Alders.
Planting Requirements - European Black Alder is adaptable to a wide range of favorable or harsh environmental conditions. It prefers moist to wet soils of variable pH that are rich and deep, but adapts to average or poor soils that are dry in summer. Growth is especially rapid in occasionally wet to permanently wet areas, such as floodplains , streambanks, and ditches. Black Willow is a good companion tree with a much finer texture. It is a good pioneer species of cut-over sites, and will self-sow to form a colony of saplings within a few years of initial seed production. It grows in full sun to partial shade, and is found in zones 4 to 7.
Potential Problems - European Black Alder, while capable of having a few minor disease and pest problems, is usually trouble-free.