Thursday, April 3, 2008
The tree species Acer saccharum is commonly known as the sugar maple. It is a prominent tree in the hardwood forests of northeastern North America. This maple normally reaches heights of 15 m (50 feet) to 24 m (80 feet) tall .
The leaves are deciduous, 8-15 cm long and equally wide with five palmate lobes. The basal lobes are relatively small, while the upper lobes are larger and deeply notched. In contrast with the angular notching of the Silver Maple, however, the notches tend to be rounded at their interior. The fall color is often spectacular, ranging from bright yellow through orange to fluorescent red-orange. The leaf buds are pointy and brown colored. The recent years growth twigs are green, and turn dark brown.
The flowers are in corymbs of 5-10 together, yellow-green and without petals; flowering occurs in early spring after 30-55 growing degree days. The fruit is a double samara with two winged seeds, the seeds are globose, 7-10 mm diameter, the wing 2-3 cm long. The seeds fall from the tree in autumn.
It is closely related to the Black Maple, which is sometimes included in this species but sometimes separated as Acer nigrum. The western American Bigtooth Maple (Acer grandidentatum) is also treated as a variety or subspecies of Sugar Maple by some botanists.
The Sugar Maple is also often confused with the Norway Maple, though they are not closely related within the genus. The Sugar Maple is most easily identified by clear sap in the leaf petiole (the Norway Maple has white sap), brown sharp-tipped buds (the Norway Maple has blunt green or reddish purple buds), and shaggy bark on older trees (the Norway Maple bark has small grooves). Also, the leaf lobes of the Sugar Maple have a more triangular shape, in contrast to the squarish lobes of the Norway Maple.
Ecology
The sugar maple is widespread, and is considered secure (except at the edges of its range).