The European Alder, Alnus glutinosa, is a species of tree in the Birch family, native to most of Europe, southwest Asia and northern Africa. It thrives in wet locations where it is associated with the bacterium Frankia alni enabling it to grow in poor quality soils. It is of medium size growing to a height of up to 100 ft. and has short-stalked rounded leaves and separate male and female flowers in the form of catkins. The small, rounded fruits are cone-like and the seeds are dispersed by wind and water.
It is a pioneer species, colonizing vacant land. Its usual habitat are forest edges, swamps and riverside corridors.
