Maples (Acer spp.) are an important group of forest trees in New York State. Sugar maple is the state tree, and maples provide maple syrup, valuable hardwood timber, wildlife foods, beautiful fall colors, lawn trees, and watershed protection.
Of the sixteen or more maples east of the Rocky Mountains, eight are found with moderate to high frequency in some parts of the state. These include: sugar maple (Acer saccharum), red maple (Acer rubrum), silver maple (Acer saccharinum), striped maple (Acer pensylvanicum), Norway maple (Acer platanoides), box-elder (Acer negundo), mountain maple (Acer spicatum), and black maple (Acer nigrum). Only the first three are described in this list. Other maples in the state that are less common and typically escaped from horticultural plantings include: hedge maple (Acer campestre), Amur maple (Acer ginnala), Japanese maple (Acer palmatum), and sycamore maple (Acer pseudoplatanus).
Maples as a group are readily distinguishable from other trees by the opposite arrangement of buds, leaves, and twigs, together with the characteristically shaped simple maple leaf (box-elder is the only exception, having compound leaves). The fruit of the maple group is also distinctive. They are without exception winged seeds, borne in pairs and clusters of pairs, and commonly called maple samaras.
Striped maple is an increasingly abundant species in the maturing and shady forests of the state. It thrives in shade and is restricted to the subcanopy. Striped maple reproduces easily and sometimes forms a dense understory inhibiting the reproduction of other species. This species is distinguished by bright green bark with white stripes, large goose foot-shaped leaves, and its samaras with wide-reaching wings.
Norway maple has been widely planted in residential areas, now overplanted, and considered an invasive weed in some of the many areas of the state where it has naturalized. There are many other more appropriate species that should be considered for ornamental planting. Norway maple is recognized by large blunt terminal buds, interlacing and often spiraling black bark ridges, and a broad leaf on a long stalk. The leaf stalk has a milky sap when broken. The species was removed from some sections of New York City and Long Island during an infestation of the Asian Longhorned beetle (Anoplophora glabripennis Motschulshy), an exotic insect that feeds on and reproduces in Norway maple, other maples, and a variety of other hardwoods.
Box-elder is a medium-sized tree found in moist locations at lower elevations, occasionally common, and its greatest value is stream bank stabilization and shading of streams. It is one of a few maple species with a compound leaf. It has no commercial value, and its weak wood makes it unsuitable for residential areas.
Mountain maple is recognized by the downy hairs on current-year twigs and buds and by its small size. Common only to moist ravines, steep slopes, and higher elevations, it has no commercial value but is a pleasant tree to encounter when hiking.
Black maple is similar to sugar maple and often considered as only a variety of sugar maple. Black maple is distinguished with difficulty from sugar maple by its drooping leaf edges and tips, hairy lower surface of the leaves and orange-brown dull twigs. Black maple's fall color is typically yellow compared to the brilliant orange to amber of sugar maple.
The other maples that occur in New York State are seldom encountered in the woods, but may be found near residential areas where seeds from planted specimens have become established.