GENUS I. 



MAPLE FAMILY 



8. Acer glabrum Torr. Dwarf or Rocky 

 Mountain Maple. Fig. 2811. 



Acer glabrum Torr. Ann. Lye. N. Y. 2: 172. 1826. 

 Acer tripartitum Nutt. ; T. & G. Fl. N. A. i : 247. 1838. 



A shrub, or small tree, with maximum height of 

 about 35 and trunk diameter of 12'. Leaves i'~3' 

 long, often broader, glabrous on both sides, or puber- 

 ulent when young, 3-5-lobed, the lobes acute or 

 obtusish, sharply serrate, the sinuses acute; flowers 

 yellowish green, in numerous small lateral and term- 

 inal sessile corymb-like racemes ; pedicels short, gla- 

 brous, erect or ascending; samaras glabrous, shin- 

 ing, 9"-is" long, little diverging; wing 4"-6" wide. 



Borders of streams and hillsides, northwestern Ne- 

 braska to Montana and throughout the Rocky Mountain 

 region, south to Arizona, west to the Sierra Nevada. 

 Wood hard, light brown. Weight per cubic foot 37 Ibs. 

 Soft, shrubby or bark-maple. May. 



9. Acer pennsylvanicum L. Striped, Goose-foot 

 or Northern Maple. Moosewood. Fig. 2812. 



Acer pennsylvanicum L. Sp. PI. 1055. 1753. 

 Acer striatum Du Roi, Diss. Inaug. 58. 1771. 



A small tree, with maximum height of about 35 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 cor- 

 date 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, i' 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 Ibs. Ascends to 

 5000 ft. in North Carolina. Northern maple. May- 

 June. 



10. Acer spicatum Lam. Mountain Maple. 

 Fig. 2813. 



Acer spicatum Lam. Encycl. 2: 381. 1786. 

 Acer moiitaniiin Ait. Hort. Kew. 3: 435. 1789. 



A shrub, or rarely a small tree, with maximum 

 height of about 30 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 i"- 

 ij"broad, greenish yellow, unfolding after the leaves; 

 petals linear-spatulate ; samaras g"-io" long, some- 

 what 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 Ibs. Ascends to 5000 ft. in North Carolina. Moose-, 

 swamp-, water- or low maple. May-June. 



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