Norway maple (Acer platanoides L.) was introduced to North America from Europe. The trees are easily cultivated and have been domesticated with many different cultivars or varieties. They are commonly planted as ornamental street trees because they tolerate salt and are able to grow in small spaces and compacted soils. Now they occur increasingly where they have not been planted and not wanted. In some natural areas they are becoming the dominant species, a problem reported from New Jersey to Ontario and even in Gaspésie, Quebec.