Norway maple was originally introduced into North America by botanist John Bartram of Philadelphia who received seedlings from Philip Miller of London in 1756. He sold 2 Norway maples to George Washington in 1792 for planting at Mount Vernon and soon the tree became one of the most popular street trees. It tolerates poor soils and air pollution and was originally planted to replace Elms when Dutch elm disease decimated our street tree population.
The tree is usually 40 to 60 feet tall but in some cases has been reported of growing up to one hundred feet tall. The canopy is rounded and can spread 60 to 80 feet wide. The leaves are oppositely arranged and have 5 lobes.
The trunk has grayish brown bark with regular shallow groves. It can be readily distinguished from other maples because the leaves and twigs ooze milky sap when cut or torn. Norway maple is the most widespread maple in Europe where it occurs from southern Scandinavia to the Caucasus Mountains, Turkey, and northern Iran.
Norway maple reproduces by seed, which it produces in copious amounts. The winged fruits (samaras) are distributed by the wind; the seeds germinate readily, even in dense shade, and grow quickly when young.
Many of the features that made this a desirable tree to plant by roadsides are also why it has become invasive. Being hardier than many native tree species has allowed it to out compete and thrive. The ability of this species to grow in deep shade makes it particularly threatening to native forest habitats. Like many invasives, its ability to grow quickly gives it the upper hand when gaining control of an area.
Hand pulling is acceptable for small saplings of this species, with mechanical removal and a "cut-and-dab" chemical treatment needed for larger trees. Make sure to bag all limbs that may contain seed pods to prevent the spread of the plant. Foliar spray is not recommended as it can be harmful to the surrounding flora and fauna. See the invasive removal page for how to carry out these methods. Any removal within 100 feet of wetland resource areas, including certified vernal pools, or within 200 feet of a perennial stream may require approval from the Concord Natural Resources Commission. Please contact the Division of Natural Resources before you begin.
The following native plants can serve as a good replacement of the Norway Maple in a garden: