[Acer nigrum var. glaucum (F. Schmidt) Fosberg, moreAcer nigrum var. saccharophorum (K. Koch) R.T. Clausen, Acer saccharum var. glaucum (F. Schmidt) Sarg., Acer saccharum var. rugellii (Pax) Rehder, Saccharodendron saccharum (Marsh.) Moldenke]
Tree to 30 m tall, trunk to 1.8 m in diameter Leaves: opposite, stalked, bright green above, lighter green beneath, 7.5 to 20 cm long and wide, usually five-lobed, few-toothed, undersides covered with a whitish waxy coating (glaucous) and slightly hairy. Leaves turn yellow to scarlet red in the fall. Flowers: either male or female, found on the same (monoecious) or different (dioecious) plants, borne in few-flowered clusters, greenish yellow. Fruit: winged (samara), paired, 3 - 3.5 cm long, with wings spread to a 60-degree angle. Bark: dark gray to grayish brown, smooth when young, becoming deeply furrowed. Twigs: smooth, changing from green to orangish or reddish brown to gray. Terminal buds: reddish brown, 5 - 8 mm long, conical, pointed, with slightly hairy scales.
Similar species: Acer saccharum var. schneckii has long, shaggy hairs on the lower leaf surface and leaf stalk, and the margin curls under.
Flowering: April to mid May
Habitat and ecology: Undisturbed woods, well-drained uplands, and lowland but not swampy areas.
Occurence in the Chicago region: native
Notes: Maple syrup is made from the sap of A. saccharum in very early spring. To make one liter of syrup, 30.25 liters of sap are needed. The wood is very hard and durable, making it a desirable material for furniture, cabinets, tool handles, musical instruments, and flooring. This is the state tree of Wisconsin.
Etymology: Acer is derived from a Latin word meaning sharp, which refers to the hardness of the wood. Saccharum is the botanical name for the genus sugarcane, which comes from the Greek word saccharon, meaning "a sweet juice."