Alnus glutinosa 'Imperialis'
Common name: 
Imperialis Black Alder
Pronunciation: 
AL-nus glu-ti-NO-sa
Family: 
Betulaceae
Genus: 
Alnus
Type: 
Broadleaf
Native to (or naturalized in) Oregon: 
No

  • Broadleaf, deciduous, medium sized tree, slow growing, pyramidal, arching branches, to about 30 ft tall with a spread of 20 ft (9 x 6 m).  Leaves medium green and deeply incised, giving the tree a filigree-like appearance.

  • Sun, best in moist soil but reportedly adaptable to different soil types, acidity, and drainage

  • Hardy to USDA Zone 4

  • Caution: Alnus glutinosa is a moderate to serious invasive species of wet sites in USA, maritime Canada, Australia, India, Republic of Korea, and New Zealand.  It is widespread in the Great Lakes region and present in 18 states.

Click image to enlarge
  • plant habit

    plant habit

  • branches

    branches

  • leaves

    leaves