Norway Maple tree Norway maple trees

Norway Maple

Acer platanoides

2019 Status in Maine: Widespread. Very Invasive.

Description: Extremely shade-tolerant, canopy-height tree, often planted. Cultivars include "Crimson King" which has purple-red color. Leaves: Opposite, 5-lobed with pointed tips but without other teeth. Broken petiole oozes white sap – distinguishes this species from native maples. Winter buds are reddish-green and rounded. Flowers: Tiny, yellow-green, high in canopy, early spring. Fruit: Typical maple samara but with a very wide angle. Bark: Furrowed, dark gray, not shaggy like native maples.

Native range: Europe, Eastern Asia. How arrived in U.S.: As an ornamental and shade tree.

Reproduction: By seeds which are dispersed short distances by wind or small mammals; occasional long-distance transport by water might be possible.

Habitat: Forests, forest edges, open areas. Extremely shade-tolerant, can germinate and compete under a closed canopy.

Similar native species: Norway maple could be mistaken for sugar maple (A. saccharum), but Norway maple has milky petiole sap, furrowed bark, and reddish-green, rounded buds, whereas sugar maple lacks milky sap, has shaggy bark, and has brown, pointed buds.

Similar non-native species: Amur maple (Acer ginnala) is a small tree, has much smaller, narrower leaf shape, and has toothed leaves.

Documented Ecological Impacts

Fact Sheets and Identification Links

Acer platanoides leaves Norway maple leaves

Control Methods

Seedlings can be pulled up*; saplings can be pulled with a weed lever or cut, but re-sprouting will occur so follow-up will be necessary. Longevity of seeds is not known. Larger trees can be cut, but will also re-sprout unless the cut stump is immediately treated with concentrated herbicide (glyphosate or triclopyr). However, this is not effective in early spring due to sap rising. Repeated follow-up cutting can control re-sprouting from cut stumps, but persistence is required, sometimes for many years. Foliar spray can also be effective for seedlings, short saplings, or re-sprouts (glyphosate or triclopyr), as long as you can reach the top of the plant. For stems up to about 4-6" diameter, the basal bark treatment can be effective any time of year(spray lower 18-24" of trunk with triclopyr with penetrating oil). In urban or suburban areas where trees provide valuable shade, a phase-out approach (removing trees gradally over time) with re-planting of native tree species may be advisable.

* Correctly dispose of all plant parts † Follow all label directions when using herbicides

Control Technique Video Demonstrations

  • No appropriate control videos found
Norway maple bark Norway maple bark

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