Voi,. II.] 



MAPLE FAMILY. 



399 



6. Acer glabrum Torr. Dwarf or Rocky 

 Mountain Maple. (Fig. 2377.) 



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 

 puberulent when young, 3-5-lobed, the lobes acute 

 or obtusish, sharply serrate, the sinuses acute; 

 flowers yellowish green, in numerous small lateral 

 and terminal sessile corymb-like racemes; pedicels 

 short, glabrous, erect or ascending; samaras gla- 

 brous, shining, 9 // -i5 // long, little diverging; wing 

 4"-6" wide. 



Borders of streams and hillsides, northwestern Ne- 

 braska and throughout the Rocky Mountain region, 

 south to Arizona, west to the Sierra Nevada and Brit- 

 ish Columbia. Wood hard, light brown. Weight per 

 cubic foot 37 Ibs. May. 



7. Acer Pennsylvanicum L/. Striped or 

 Goosefoot Maple. Moosewood. (Fig. 2378.) 



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 lines. Leaves large, 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 green- 

 ish yellow, V-4" broad; unfolding after the leaves; 

 petals obovate; samaras glabrous, i' long, widely di- 

 vergent, the wing 4 // -5 // wide. 



In rocky woods, Nova Scotia to Lake Superior, south, 

 especially along the mountains to Georgia, and Tennessee. 

 Called also False or Striped Dogwood and Whistle-wood. 

 Wood soft, satiny, light brown ; weight per cubic foot 33 Ibs. 

 Ascends to 5000 ft. in North Carolina. May-June. 



8. Acer spicatum I^am. Mountain Maple. 

 (Fig. 2379.) 



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

 Acer monlanum 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'-$' 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"-!^" broad, greenish yellow, unfolding after the leaves; 

 petals linear-spatulate; samaras 9 // -io // long, somewhat di- 

 vergent, the wing 3 // -4 // wide. 



Damp rocky woods, Newfoundland and James' Bay to Manitoba, 

 south, especially along the mountains, to North Carolina, Ten- 

 nessee and Minnesota. Wood soft, light reddish brown; weight 

 per cubic foot 33 Ibs. Ascends to 5000 ft. in North Carolina. 

 May-June. 



