Alnus glutinosa

Black alder is in the birch or Betulaceae family and is native from most of Europe to Siberia, south into northern Africa, and is a broadly-conical tree reaching up to 24 m tall. It is usually found in swamps and along riverbanks in the wild. It is sometimes found naturalized in northeastern North America.

• Leaves are alternate, simple, shallowly-toothed, broadly-rounded and up to 10 cm long and 7.5 cm across, smooth, deep green above, light green and tufts of hairs in the vein axles beneath.
• Species is monoecious. Flower catkins emerge in early spring before the leaves. Male catkins are up to 10 cm long, drooping and are dull purple turning to dark yellow, in clusters of 3 to 5; female catkins are small (up to 2 cm long), red, upright clusters.
• Fruit is a cone-like woody catkin, egg-shaped and 2 cm long, initially green, ripening to brown in late fall. It is persistent through the winter (non-fragmenting).
• Twigs are greenish brown; buds are stalked, purplish brown in color and somewhat three sided.
• Bark is brown and smooth later turning dark with many warty stripes.