The Norway Maple is a fast-growing, pollution-tolerant tree that was brought to North America from Europe in the mid-1700s. It was originally planted in gardens and cities because it could survive in compacted soil, grow quickly, and throw lots of shade. In fact, it became one of the most popular street trees in the United States during the 20th century — especially after Dutch Elm Disease wiped out thousands of native elms in cities like Norwalk and Bridgeport.
But the very traits that made it seem appealing — fast growth, deep shade, and adaptability — are exactly what make it invasive.
Norway Maples:
- Leaf out early in spring and hold their leaves longer into fall than native trees, which means they block sunlight from reaching wildflowers and under story plants for a longer portion of the year.
- Have shallow, aggressive roots that hog water and nutrients, making it nearly impossible for grass or gardens to thrive under them.
- Produce huge numbers of seeds — those little “helicopter” samaras — which spread and sprout rapidly, forming dense clusters of saplings that can take over an entire woodland edge.
- Support very few native insects. Studies show that Norway Maples host less than 5% of the caterpillar species supported by our native maples like the Sugar Maple (Acer saccharum) or Red Maple (Acer rubrum) (Tallamy; National Wildlife Federation). This means birds, especially nesting songbirds, find very little to eat on them.
Yes, Norway Maples do photosynthesize and help produce oxygen. Yes, their leaves eventually decompose and return nutrients to the soil — just like any tree. But a tree is more than just shade and air. It’s part of a living food web, and the Norway Maple is a dead end in that web.
When these trees spread, they replace native species and reduce biodiversity — which makes forests weaker, wildlife hungrier, and ecosystems more vulnerable to climate stress.
That’s why Connecticut has banned the sale and planting of Norway Maples. They are officially listed as invasive — meaning they spread aggressively and harm native species. But not all non-native trees are invasive. For example, ornamental cherries, ginkgo trees, and Japanese maples are non-native but don’t take over wild areas and can be responsibly planted in yards and parks.
So what’s the difference?
“Non-native” just means a tree isn’t from here.
“Invasive” means it doesn’t belong and it causes harm.
In a time when climate change is putting stress on all living systems, planting the right trees matters more than ever. When we choose native trees like Red Oak, White Pine, Flowering Dogwood, or Eastern Redbud, we help local wildlife survive and keep our ecosystems strong. These native trees evolved alongside local insects, birds, and soil life — and they play well together.
If you’re planting a tree — or replacing a Norway Maple — consider a native species that feeds more than just the eye. You can explore a full list of Connecticut-native trees here:
norwalktreealliance.com/connecticut-native-tree-inventory
Every tree planted is a choice. For the kids growing up today — and for the forests of tomorrow — let’s choose trees that give more than they take.
Sources:
- Connecticut Invasive Plant Working Group (CIPWG)
- Doug Tallamy, Bringing Nature Home
- National Wildlife Federation: “The Wildlife Benefits of Native Trees”
- Morton Arboretum Tree Profile: Acer platanoides
- Brandywine Conservancy – Norway Maple Invasiveness
- Woodland Trust UK – A-Z Tree Guide
- GardenersPath – “How to Identify and Remove Norway Maples”
- Norwalk Tree Alliance – Native Tree Inventory