Plant Family: Sapindaceae
Growth Form: Large tree up to 30 meters in height.
Leaves: Opposite, simple, with five pointed lobes; milky sap exudes from the base of broken leaf petioles. The fungus Rhytisma acerinum often causes large dark spots to develop on the leaves by late summer, providing a characteristic field mark, although these are cosmetic and do not hurt the tree.
Bark: Light gray and smooth on young trees, becoming dark gray and tightly fissured on older trees.
Flowers: Small, greenish yellow, held in spherical clusters, appearing before the leaves in early spring.
Fruits: Paired samaras with widely spread wings.
Habitat: A common street tree in New England towns and cities that has escaped from cultivation to nearby upland woods.
Range: Its native range includes northern, central, and eastern Europe. It is well established throughout New England and most of the northern tier of States.
Similar Species: Sugar Maple has very similar leaves, but the broken petioles lack milky sap and the bark on mature trees has raised scaly plates, unlike the tightly fissured bark of Norway Maple.
Comments: Norway Maple was first introduced to North American cities in the 18th century because it provides shade and tolerates pollution and poor soils. It easily spreads from cultivation, however, and is considered an invasive species that crowds out and shades out native forest trees.
