Beginning an article like this is always difficult. There are many trees, shrubs and perennials that deserve extra attention, and it's tough to pick which makes the cut. It's fun to pick unusual plants, but too often they're not readily available. It's convenient to pick common plants, but too often they've been reported on by other people. So for this article I decided to try something a little different and write about the little known history and traits of a common plant, the Norway maple. This article won't add anything to your plant palate, but hopefully it will add a little bit to your base of knowledge about this useful, but often misunderstood plant.

Despite its ubiquitous nature in North American landscapes the Norway maple is not a native tree (as you might guess from its common name). It was brought over from Europe in the late 18th century by William Hamilton for the express purpose of providing shade on his property which was one of the great American botanical gardens of the time, and unfortunately one that hasn’t survived; Hamilton's land eventually being turned into a cemetery (Spongberg, 1990).

Norway maple tends to grow faster than its American counterpart, the sugar maple, and out-competes sugar maple under most conditions. It is more efficient at photosynthesizing, its leaves stay on longer, and its foliage is more dense that that of the sugar maple.  (It's no wonder this tree is so popular!) This tree is considered invasive, particularly on the East coast where it is well suited to the environment and easily outgrows most of its competitors.  Here in the Midwest this maple is still considered invasive, but less so than in other parts of the country. The Norway maple is tolerant of poor soil and drought and it handles shade better than most native plants too. To intercept all of the available light it can it has a very dense canopy which limits the number of plants that can grow underneath. Additionally, the Norway maple handles air pollution much better than many other trees making it very tolerant of urban environments, particularly places like parking lots (Webb et al., 2001; Kloeppel and Abrams, 1995).

The Norway maple is a true enigma because the very things that make this tree invasive also make it a great tree for streets and cities. Perhaps the way to treat this tree is not as a tree for all situations (despite the fact that it will grow in almost all situations) but instead as a great tree for the urban environment to be planted where its seeds are unlikely to make it to fertile ground where it could push our native plants into the background.

References:
Kloeppel, B. D. and M. D. Abrams.  1995.  Ecophysiological attributes of the native Acer saccharum and the exotic Acer platanoides in urban oak forests in Pennsylvania, USA.  Tree Physiology 15, 739-746.

Spongberg, S. A. 1990.  A Reunion of Trees.  Harvard University Press, Cambridge, MA.

Webb, S. L., Pendergast, T. H., and M. E. Dwyer.  2001.  Response of native and exotic maple seedling banks to removal of the exotic, invasive Norway maple (Acer platanoides).  Journal of the Torrey Botanical Society 128(2): 141-149.