This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Fig. 2812
Acer pennsylvanicum L. Sp. Pl. 1055. 1753. Acer striatum Du Roi, Diss. Inaug, 58. 1771.
A small tree, with maximum height of about 35o and trunk diameter of about 8', the smoothish green bark striped with darker bands. Leaves larger, often 6'-8' long, broadest above the middle, thin, glabrous above, sparingly pubescent beneath when young, slightly cordate or truncate at the base, finely serrate or serrulate all around, 3-lobed near the apex, the lobes short and acuminate to a long tip; racemes terminal, narrow, drooping, 3-4' long; flowers greenish yellow, 3"-4" broad; unfolding after the leaves; petals obovate; samaras glabrous, 1' long, widely divergent, the wing 4"-5" wide.
In rocky woods, Nova Scotia to Lake Superior, south, especially along the mountains to Georgia, and Tennessee. False or striped dogwood. Whistle-wood. Wood soft, satiny, light brown; weight per cubic foot 33 lbs. Ascends to 5000 ft. in North Carolina. Northern maple. May-June.
Fig. 2813
Acer spicatum Lam. Encycl. 2: 381. 1786. Acer montanum Ait. Hort. Kew. 3: 435. 1780.
A shrub, or rarely a small tree, with maximum height of about 300 and trunk diameter of 8', the bark green, not striped. Leaves 3'-5' long, glabrous above, pubescent beneath, at least when young, 3-5-lobed, coarsely serrate, lobes acute or acuminate; racemes compound, erect, rather dense; flowers 1"-i*"broad,greenish yellow, unfolding after the leaves; petals linear-spatulate; samaras 9"-10" long, somewhat divergent, the wing 3"-4" wide.
Damp rocky woods, Newfoundland and James' Bay to Manitoba, south, especially along the mountains, to North Carolina, Tennessee. Michigan, Iowa and Minnesota. Wood soft, light reddish brown; weight per cubic foot 33 lbs. Ascends to 5000 ft. in North Carolina. Moose-, swamp-, water- or low maple. May-June.
Fig. 2814
Acer Negundo L. Sp. Pl. 1056. 1753. Negundo aceroides Moench, Meth. 334. 1794. Negundo Negundo Karst. Deutsch. Fl. 596. 1880-83.
A tree with maximum height of 6o°-7o° and trunk diameter of 2°-3 1/2°. Leaves pinnately 3-5-foliolate; leaflets ovate or oval, thin, pubescent when young, nearly glabrous or pubescent when old, 2-5' long, 1-3' wide dentate, slightly lobed or sometimes entire, acute or acuminate at the apex, rounded, or the terminal one somewhat cuneate at the base; flowers dioecious, drooping, very small, appearing a little before the leaves; samaras glabrous, 1'-1 1/2' long, the broad wing finely veined, the united portion constricted at the base.
Along streams, Maine and Ontario to Manitoba, south to Florida, Texas and Mexico. Rare near the Atlantic Coast. Wood soft, weak, white; weight per cubic foot 27 lbs. Used for woodenware and paper pulp. Sugar maple. Red river maple. Black or maple-ash. April.
Acer interior Britton, Western ash-leaved maple, of the Rocky Mountain region, and found in western Kansas and Nebraska, has thicker leaves, the united portions of the samaras not constricted at the base.
 
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