Native to the northern hemisphere:  🇪🇺 Europe, Asia, and western 🇨🇦 Canada and 🇺🇸 USA.  Part of alder  genus Alnus and birch / alder / hazel / hornbeam  family Betulaceae.

Different subspecies specialize in different areas, including:

Uses by native peoples
(Ethnobotany database)
  Alnus hosts caterpillars of 267 species
of butterflies and moths, in some areas.

Learn more about green alder Alnus viridis

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