Invasive Species Corner

Norway maples are a popular choice when it comes to planting ornamental trees, but did you know they are considered invasive? They are deciduous trees with large maple leaves. Leaves can vary in colour but are most commonly green or dark red.

Norway maples are commonly planted in urban areas, due to their large canopies and their aesthetic qualities, however they have very brittle branches that commonly break off in the wind. The crimson maple is a variety of Norway maple with dark red leaves. Due to the red colour of its leaves the crimson maple is often mistaken as a red maple, which is a native species.

Despite its attractive qualities, Norway maples pose a real threat to native biodiversity. Norway maples are fast growing with a densely packed and shaded canopy. They can outcompete native wildlife with a widespread network of shallow roots that emit chemicals toxic to other species. In extreme cases, the lack of ground vegetation can be so strong that soils begin to erode. Although this may not be a big concern in urban areas, once these trees access wild areas, they can take over rapidly through the spread of seedlings.

When planting a tree, it is important to do your research and know what you are planting before it goes in the ground. Make sure you are aware of the impacts that species may have and determine a management plan for your tree.

Think before you plant!
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