Norway Maple
Acer platanoides · Sapindaceae · Deciduous
An introduced European maple now among the most planted street trees in North America and invasive in many regions. It casts dense shade that suppresses undergrowth, and it has one identification test that is completely unambiguous.
Quick facts
- Arrangement
- opposite
- Leaf
- Broad five-lobed leaf, wider than it is long, with lobes tapering to fine bristle tips.
- Bark
- Grey-black with regular, tight, shallow furrows in a close diamond pattern — noticeably more uniform than a native maple's.
- Fruit
- Samaras joined in a nearly straight line, close to 180 degrees, which is distinctive.
- Height
- 40–70 ft
How to confirm it
- Snap the leaf stalk from the twig: milky white sap oozes out. No native North American maple does this.
- Samara wings spread almost flat, nearly in a straight line.
- Leaf wider than long with fine bristle tips on the lobes.
- Bark furrowed in a tight, regular diamond pattern.
What it is confused with
One observation settles each of these.
The milky sap test settles it in seconds. Norway maple bleeds white; sugar maple runs clear.
Where it grows
Streets, parks and yards across North America, and spreading into woodland where it is invasive.
Start here: opposite or alternate?
Look at where the leaves join the twig. Are they in matched pairs directly across from each other, or staggered one after another? The vast majority of trees are alternate, so finding an opposite tree removes almost everything else in one step.
In North America, opposite-leaved trees are remembered as MAD Cap Horse: Maple, Ash, Dogwood, Caprifoliaceae (viburnums and elders), and Horse chestnut. That is very nearly the whole list.
Check partway along a healthy twig rather than at the tip, where crowding can make alternate leaves look paired. And check more than one twig.