Alnus glutinosa 'Imperialis'

Cut-leaf European Alder (Black Alder)

Form and Growth Characteristics:
Plant Type - Tree
Growth Rate - weak pyramidal to narrow pyramidal. Fast in youth, tends to slow down; 24-30’ per year over a 20 year period.
Mature Height - 40-60'
Mature Width - 20-40'
Longevity -

Ornamental Characteristics:
Flower - In March before leaves. Male flowers – reddish brown 2-4" long catkins. Female flowers – purplish, egg-shaped
Fruit - Nutlet, borne in persistent 0.33 to 0.66” long ovoid strobile, on 0.5-1” long peduncles matures in October-November
Leaf - Alternate, simple, 2-4” long, 3-4” wide, glabrous above, axillary tufts beneath, 6-8 vein pairs; petiole-0.5-1” long. Leaves of this cultivar are deeply cut, bright green.
Fall Color - none. Leaves fall off green or brown.
Bark - Young bark is gray-green or greenish brown; brown with age.
Other Features - ‘Imperialis' deeply cut, light green leaves.
Possible Use - Wet sites, parks, large areas.
Season Of Interest -

Culture and Care:
Care Requirements - Transplants readily; prune in winter or early spring; if used along waterways will seed in along the banks and eventually cover large areas; species can grow submerged in the water; a nitrogen fixing species. Zone 4-7.
Native Habitat - Species native to Europe, western Asia, northern Africa.
Diseases and Insects - Powdery mildew rarely serious, cankers can be a problem, leaf rust-rarely serious, woolly alder aphid, alder flea beetle, alder lace bug, leaf miner, sawfly, and tent caterpillar
Strength - For extremely wet areas the tree has distinct possibilities.
Weakness - Does not perform well in the heat of the South.

Plants of this taxon:

Find Related Plants:
- Other plants with the common name Alder.
- Other plants of the family Betulaceae.
- Other plants of the genus Alnus.
- Other plants of the species Alnus glutinosa.