Alder-leaved Whitebeam (Alniaria alnifolia) — identification, habitat & look-alikes

Alder-leaved whitebeam is an East Asian tree grown in U.S. gardens and arboretums for its white spring flowers, red fall fruit, and fall color. Unlike most mountain ashes, it has individual, oval leaves rather than leaves divided into leaflets. It is also called Korean mountain ash.

Appearance

Growth form: It is a medium to large tree, often more than 40 ft (12 m) tall in cultivation.
Leaves: Each alternate leaf is simple and oval, with unequal teeth around the edge. Fall color can mix yellow, orange, and brown.
Flowers: Small white flowers form flat-topped clusters about 2–3 in (5–8 cm) wide in spring.
Fruit: Clusters of red, berry-like appear from late summer into fall.

Look-alikes

American mountain-ashSorbus americana

American mountain ash has compound leaves with 9–17 separate leaflets. Alder-leaved whitebeam has one simple, oval blade per leaf.

Why they get mixed upBoth can have clusters of white flowers and red-orange fruit, and both are called mountain-ash.

Where it lives

Typical habitats: Arboretums and gardens
Sunny lawns
Range: The species is native to Korea, Japan, China, and nearby parts of East Asia. In the United States it is a nonnative ornamental rather than a wild native tree.
Preferred conditions: It grows best in full sun with steady moisture and well-drained soil. It is recommended for 4–7; avoid dry, polluted street sites.

Growing it

Care: Give it full sun and moist, well-drained soil. It is moderately sensitive to drought and does not handle harsh urban sites well.

Name and classification

About the name: Botanists also place this species in other genera, so plant labels may use names such as Sorbus alnifolia.

Conservation

IUCN Red List: LCLeast ConcernLow risk of extinction

13 sources