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European Black Alder
Alnus glutinosa

Other common names: Black Alder

French names: Aulne glutineux

Family: Birch Family (Betulaceae)

Group: Alders

Distinctive features: Shrub; Leaves roundish, usually indented at the tip; bark speckled.

Similar species:
  •   Speckled Alder (Alnus incana) - very similar, often confused. Leaves are more pointed at the ends and are double-toothed.

  •   Green Alder (Alnus viridis) - leaves are pointed at the ends.

  •   Alder-leaved Buckthorn (Rhamnus alnifolia) - not an Alder.


Flowers: Spring

Leaves: Alternate, Simple, Toothed;  Roundish.

Habitat: Wet Areas, Bogs and Fens, Lakeshores, Pond Margins, Swamps, Shrub Swamps;  Wet areas, and nearby wet areas.

Books: Trees in Canada: 305   

Native/Non-native: Non-native

Status: Locally common.

Notes: Easily confused with Speckled Alder (Alnus incana). Can be invasive.

Origin and Meaning of Names:
 Scientific Name: glutinosa: sticky


See Also:
  •   Alder: The Nitrogen Fix, from The Monday Garden, by Sue Sweeney


Photographs: 144 photographs available, of which 15 are featured on this page. SCROLL DOWN FOR PHOTOGRAPHS.

Range Map is at the bottom of the page

European Black Alder (Alnus glutinosa)

European Black Alder leaves. Note that they are somewhat rounded.

European Black Alder (Alnus glutinosa)

Typical leaf.

European Black Alder (Alnus glutinosa)

The leaves often have indented tips. Also note that they are not double-toothed like those of Speckled Alder (Alnus incana).

European Black Alder (Alnus glutinosa)

Underside of the same two leaves. Note the prominent veins.

European Black Alder (Alnus glutinosa)

For comparison, here are the leaves of the three Alders:
-Green Alder (Alnus viridis) (L)
-Speckled Alder (Alnus incana) (M)
-European Black Alder (Alnus glutinosa) (R).

European Black Alder (Alnus glutinosa)

Leaves opening up in the spring.

European Black Alder (Alnus glutinosa)

Buds. Note that they are stalked.

European Black Alder (Alnus glutinosa)

Closeup of a bud.

European Black Alder (Alnus glutinosa)

Pollen catkins.

European Black Alder (Alnus glutinosa)

Extreme closeup of a pollen catkin.

European Black Alder (Alnus glutinosa)

Seed catkins, not yet open. Note the long stalks - this is distinctive of this species.

European Black Alder (Alnus glutinosa)

Open seed catkins.

European Black Alder (Alnus glutinosa)

Typical trunk and bark - note the spotted appearance - this is very similar to Speckled Alder (Alnus incana).

European Black Alder (Alnus glutinosa)

Less typical trunk and bark.

European Black Alder (Alnus glutinosa)

This Alder grows to the size of a small tree.


Range map for European Black Alder (Alnus glutinosa)

PLEASE NOTE: A coloured Province or State means this species occurs somewhere in that Province/State.
The entire Province/State is coloured, regardless of where in that Province/State it occurs.

(Range map provided courtesy of the USDA website and is displayed here in accordance with their Policies)