Bark: Smooth and pale brown at first, becoming darker and furrowed when old.
Twigs: Slender, brown, smooth or hairy, usually with pale lenticels; leaf scars opposite, U-shaped, with 3-7 bundle traces.
Buds: Rounded, reddish-brown, hairy, up to ¼ inch long.
Leaves: Opposite, simple; blades up to 4 inches long, nearly as broad, palmately 3- to 5-lobed, drooping on the sides, the edges sparsely and coarsely toothed, green and smooth or a little hairy on the upper surface, paler and much hairier on the lower surface; leaf-stalks up to 3 inches long, very hairy. The leaves turn yellow or orange in the autumn.
Flowers: Staminate and pistillate borne separately, but sometimes on the same tree, in dense clusters, yellowish-green, appearing as the leaves unfold.
Fruit: Borne in pairs, composed of a wing with a seed at the base, greenish, up to 1 inch long.
Wood: Heavy, strong, coarse-grained, light brown.
Uses: Furniture, interior finishing, cabinets.
Habitat: Woodlands.
Range: Virginia across southern Illinois to southeastern Oklahoma, south to Texas, east to Florida.
Distinguishing Features: The Southern Sugar Maple resembles the Black Maple because of its drooping leaves, but differs by its smaller, thicker leaves.
BOX ELDER Acer negundo L.
Other Name: Ash-leaved Maple.
Growth Form: Medium tree up to 60 feet tall; trunk diameter up to 4 feet; crown wide-spreading.
Bark: Light brown, ridged when young, becoming deeply furrowed with age.
Twigs: Smooth, green, glaucous, or rarely purplish, shiny, usually with white lenticels; leaf scars opposite, U-shaped, with 5-9 bundle traces.
Buds: Rounded, white-hairy, up to ⅛ inch long.
Leaves: Opposite, pinnately compound, with 3-7 leaflets; leaflets elliptic to ovate, up to 4 inches long, about half as broad, pointed at the tip, tapering or rounded at the sometimes asymmetrical base, smooth or usually coarsely toothed along the edges or even shallowly lobed, light green and smooth on the upper surface, paler and smooth or hairy on the lower surface.
Flowers: Staminate and pistillate borne on separate trees, several in a cluster, greenish-yellow, appearing as the leaves begin to unfold.
Fruit: Borne in pairs, in drooping clusters, composed of a curved wing with a seed at the base, greenish-yellow, up to 2 inches long.
Wood: Light weight, soft, close-grained, white.
Uses: Paper pulp, interior finishing, furniture.
Habitat: Moist woods.
Range: Vermont across to Saskatchewan, south to Texas, east to Florida.
Distinguishing Features: The Box Elder most nearly resembles ashes, but differs by its green or glaucous twigs and its paired fruits.
BLACK MAPLE Acer nigrum Michx.
Growth Form: Medium tree up to 65 feet tall; trunk diameter up to 2½ feet; crown broad, with several upright branches.
Bark: Dark brown to black, smooth when young, soon becoming furrowed and scaly.
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