Author 'Francis-Sisco' (Id 190953 ) : The male flowers are catkins pendulous, purple and long. The female flowers are smaller.
The fruit is a small cone of dark brown. It contains small achenes winged. It remains on the tree throughout the year.
Some birds such as siskins of alders in the love. Lien : Http://fr.wikipedia.org/wiki/Aulne_glutineux