Norway maple

The Norway maple (Acer platanoides) is found throughout Europe, from England north through Scandinavia. This tree was introduced to the US by an English Botanist, John Bartram, in 1756 where they were sold by Bartram’s Nursery in Philadelphia. A cultivar of the Norway maple, the Crimson King Maple was imported into the country in 1792 and sold at the same establishment. The Crimson King maple leaves have a purple hue that really stand out in a landscape, especially when the tree has plenty of sunshine. Early on, the Norway maple was prized for its fast growth, tolerance to a number of harsh growing conditions, and dense shade. This tree had very few insect or disease problems, and the bright yellow fall coloration was an added bonus. The Norway maple was widely planted as a street and ornamental tree, especially from 1940- 1990. These trees were planted along Shepherdstown Pike in Sharpsburg in 1877 as part of a gathering of Civil War Veterans, known as Decoration Day, which was one of the earliest Memorial Day observations in the US. The maples were planted to shade veterans as they walked from the train station to the new National cemetery. A few of the original maples survive to this day.

The Norway maple is not without its problems, however. It grows so fast, that quite often the large buttress roots begin to encircle the trunk of the tree, causing girdling roots. Trees with girdling roots often have no root flare at the base of the tree and portions of their crown start dying, as the tree begins to strangle itself. Norway maple also suffers from Verticillium wilt, a disease that spreads through the vascular system, and quickly kills the tree. Ironically, the traits that make the Norway maple a good street tree also render it an invasive pest when it escapes into open areas, because they have very viable seed that germinates easily under many conditions, including dense shade. This “shade tolerant” plant will continue to grow throughout the understory, and will eventually gain a stronghold in the main canopy once an opening occurs. The dense foliage of the Norway maple, combined with some allelopathic properties, help to exclude understory plants from growing underneath these trees. For these reasons, the Norway Maple has been classified as an invasive exotic throughout much of its range.

Article by FCFCDB

Nature Note for 7/11/2020