Acer pensylvanicum (Striped Maple, also known as Moosewood and Moose Maple) is a species of maple native to northern forests in eastern North America from southern Ontario east to Nova Scotia and south to eastern Illinois and New Jersey, and also at high elevations in the Appalachian Mountains much farther south than in the rest of its range, to northern Georgia.
It is a small deciduous tree growing to 5-10 m tall, with a trunk up to 20 cm diameter. The young bark is striped with green and white, and when a little older, brown. The leaves are broad and soft, 8-15 cm long and 6-12 cm broad, with three shallow forward-pointing lobes. The fruit is a samara; the seeds are about 27 mm long and 11 mm broad, with a wing angle of 145° and a conspicuously veined pedicel.
The spelling pensylvanicum is the one originally used by Linnaeus.
Moosewood is an understory tree of cool, moist forests. It prefers slopes. It is among the most shade-tolerant of deciduous trees. It can germinate and persist for years as a small understory shrub, growing rapidly to its full height when a gap opens up. It does not ever become a canopy tree, however, and once the gap above it is closed, it responds by flowering profusely, and to some degree by vegetative reproduction.
The wood is soft and considered undesirable among maples. Although ecologically there is no reason to consider it a pest, foresters sometimes consider the striped maple to be a pest tree, even to the point of applying herbicides to destroy it. Its shade tolerance makes it difficult to control, as it is often present in great numbers in the understory.