Norway maple (Acer platanoides)

Norway maple Description: Creates dense shade; monopolizes soil moisture; regenerates prolifically under its own canopy, reduces overall plant diversity on a site; long lag time before early dispersers mature, then spread rapid due to heavy seed production.

Habit: Medium tree reaching 12-18 m (40-60 ft) in height and 30-60 cm (12-24 in) in diameter; crown is dense, symmetrical, and rounded; spread is approximately two-thirds of the tree?s height.

Leaves: Simple, opposite, green to bronze in color, smooth, 5-7 lobed with few teeth and broad bases up to 18 cm (8 in) wide, wider than long, petioles have milky juice, leaves retained late in autumn.

Stems: Stout twigs; smooth; olive brown; leaf scars meet to form a sharp angle; buds are plump, rounded, fleshy, green to maroon; one large bud in center with two smaller lateral buds; bark is grayish black with small furrows.

Flowers: Stalked, yellow-green in color, perfect, loose clusters; appearing before or with the leaves in spring.

Fruit and seeds: Two-winged samaras with the wings almost horizontally divergent (180 degree angle), seeds are wind dispersed; appear in late spring through summer.

Habitat: Shade tolerant; occurs in a variety of soil and moisture conditions but prefers fertile, moist, well-drained soils; found on roadsides, waste places, hedgerows, roadside thickets, disturbed and intact forest communities; somewhat resistant to drought.

Reproduction: By seed, with heavy seed crops every 1-3 years.

Similar species: Native sugar and black maples (A. saccharum, A. nigrum) do not produce milky juice; samara wings form a sharper angle.

Monitoring and rapid response: Monitor road edges and paths; stays green until November, can be identified in spring, summer and early fall by the milky sap in its leaves and stems. For large infestations, focus on highest quality areas and remove mature trees that provide a source of seed. Hand pull seedlings in spring while soil is moist. Basal bark treatment is effective for trees less than 10 cm (4 in) in diameter. Cutting and girdling are effective for trees of any size when cut surfaces are treated with herbicide.

Credits: The Michigan Natural Features Inventory (MNFI) has partnered with MISIN to provide the information in this fact sheet. Species images and/or information were used with permission from "A Field Identification Guide to Invasive Plants in Michigan's Natural Communities" and "A Field Guide to Invasive Plants of Aquatic and Wetland Habitats for Michigan.


Common Name:

Norway maple

Scientific Name:

Acer platanoides

Family:

Aceraceae
(Maple)

Duration:

Perennial

Habit:

Trees

USDA Symbol:

ACPL