Japanese Alder Alnus japonica
- Phonetic Spelling
- AL-nus juh-PON-ih-kuh
- Description
-
Tough, adaptable plant; few pest problems; tolerates short-term flooding; flower and fruiting best in full sun. Uncommon in the U.S. Good selection for difficult sites such as moist low spots or dry sites with poor soils. Woodland areas. Does not perform well south of zone 7.
Insects, Diseases, and Other Plant Problems: No serious problems.
- See this plant in the following landscape:
- Cultivars / Varieties:
-
- Tags:
- Cultivars / Varieties:
-
- Tags:
-
-
Attributes:
- Genus:
- Alnus
- Species:
- japonica
- Family:
- Betulaceae
- Life Cycle:
- Woody
- Country Or Region Of Origin:
- Japan, Korea, Manchuria
- Dimensions:
- Height: 12 ft. 0 in. - 25 ft. 0 in.
- Width: 8 ft. 0 in. - 12 ft. 0 in.
-
-
Whole Plant Traits:
- Plant Type:
- Tree
- Woody Plant Leaf Characteristics:
- Deciduous
- Habit/Form:
- Pyramidal
- Maintenance:
- Low
- Texture:
- Medium
-
-
Cultural Conditions:
- Light:
- Full sun (6 or more hours of direct sunlight a day)
- Partial Shade (Direct sunlight only part of the day, 2-6 hours)
- Soil Drainage:
- Frequent Standing Water
- Available Space To Plant:
- 6-feet-12 feet
- 12-24 feet
- USDA Plant Hardiness Zone:
- 5a, 5b, 6a, 6b, 7a, 7b
-
-
Fruit:
- Fruit Type:
- Nut
- Fruit Length:
- < 1 inch
- Fruit Description:
- ellipsoidal fruiting cones 3/4"-1" long
-
-
Flowers:
- Flower Color:
- Brown/Copper
- Gold/Yellow
- Insignificant
- Purple/Lavender
- Flower Inflorescence:
- Catkin
- Flower Bloom Time:
- Spring
- Flower Description:
- Monecious blooms appear in March yellow-brown to red-brown catkins (male flowers) appear in clusters, female flowers on short, purplish-brown strobili which persist until winter
-
-
Leaves:
- Woody Plant Leaf Characteristics:
- Deciduous
- Leaf Color:
- Green
- Leaf Shape:
- Elliptical
- Ovate
- Leaf Margin:
- Serrate
- Hairs Present:
- No
- Leaf Length:
- 3-6 inches
- Leaf Description:
- Oval, narrow leaves acuminate, serrulate, dark green leaves (to 5" long). Wedge-shaped at the base and light green underneath. Fall color unremarkable.
-
-
Stem:
- Stem Is Aromatic:
- No
-
-
Landscape:
- Landscape Location:
- Slope/Bank
- Woodland
- Design Feature:
- Shade Tree
- Resistance To Challenges:
- Dry Soil
- Insect Pests
- Poor Soil
- Wet Soil
