Norway Maple or Acer platanoides is a common tree throughout much of Europe. It has been widely introduced into North America as a street tree and for its many unique cultivars. The Norway maple is favoured also due to its tolerance of poor, compacted soils and pollution. As a result of these characteristics, the Norway maple is displacing the native sugar maple and is widely considered invasive (and has been classified as such by authoritative sources in New England, New York, Virginia, Georgia, Maryland, Wisconson, Minnesota, and other places).
The Norway maple can be recognised by its alternate, palmately lobed leaves. Certain cultivars are also characterized distinctive leaf coloration such as the deep red of Crimson King or variegated leaves of Emerald Queen.
Leaves are palmate with angular notches between the lobes. Leaf stems secrete a milky juice when broken.
Bark is gray. In mature growth, the bark is grooved. Unlike many other varieties of the maple family, mature trees do not tend to develop a shaggy bark.
The seeds or fruit of the Norway maple consist of the paired keys typical of the maple family. The wings are widely spread, approaching a 180-degree angle.
The Norway maple typically produces a large quantity of viable seeds, a factor which contributes to its invasive character.