Norway maples are native to much of Europe and portions of Asia, though it is now well-established in much of the northern US and Canada. Trees reach up to 100′ (30 m) in height.
Identification. Norway maple leaves have sharp tips that become hairlike, while most other maples have more rounded tips. Sugar maples produce clear sap, while a plucked Norway maple leaf exudes a white sap. It is easily distinguished from other maples by its leaf shape. Also, the bark is gray and shallowly grooved, rather than shaggy. The leaves are typically bright yellow in the fall.
We used to call the seed pods "helicopters," since they often spun quickly as they fell. Each helicopter contains two winged seeds that are completely opposite to each other.
Zelimir Borzan, University of Zagreb, Croatia
Branchlet with corymb, terminating developing young shoots (a-e) with deciduous (typically green) transitional leaves at their base (k).
Branchlet with mature leaves and ripe fruits (double samaras). Stalk exudes a milky sap when broken. Wings of the samaras spread are perpendicular to the pedicels ("horizontally spreading"), with conspicuously flat nutlets.
Seedling with cotyledons(c) and first pair of ordinary leaves.
Winter-branchlet; buds are reddish-brown, glossy, terminal bud is larger. Leaf-scars are opposite, horseshoe- or heart-shaped and connected extreme [opposite] laterally. After Hempel & Wilhelm, 1889.
My parents are not big fans of this tree, which, until it recently succumbed to a severe ice storm, grew to fill their front yard. It secretes chemicals that discourage the growth of other plants underneath, and creates baby trees by the truckload. In some areas Norway maples are regarded as invasives, though they remain popular as landscape plants and tolerate urban conditions well.