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STRIPED MAPLE. 

 Acer pennsylvanicum, Linnaeus. 



FORM Usually from 10-25 ft. In height with a diameter of about 6-12 inches, but may 

 attain a height of 40 feet. Trunk usually short dividing into slender and straight branches 

 which form a deep and broad crown. 



BARK Thin, rather smooth, greenish or reddish-brown, conspicuously marked with longi- 

 tudinal white streaks; later becomes rougher, darker, and less streaked. See Fig. 63. 



TWIGS Smooth, stout, at first greenish, later red, with very few inconspicuous lenticels, 

 and brown pith. Season's growth marked by 2 or sometimes 3 dark lines encircling the twig, 

 formed by fallen outer bud- scales. White longitudinal streaks appear the second season. 



BUDS Opposite, evidently-stalked, large, about 2/5 of an inch long excluding stalk, 

 tapering but blunt-pointed, red, glossy, angular, covered by a single pair of red, smooth, val- 

 vate scales enclosing a few pairs of smaller and lighter scales. Outer scales are smooth 

 on surface with ciliate margins while the inner scales are hairy as shown in opposite plate. 

 Terminal buds are large while lateral buds are smaller and closely appressed. 



LEAVES Opposite, simple, goose-foot-like, 3-lobed at apex, finely serrate on margin, rounded 

 at base, rusty -pubescent below. Petioles long, grooved, with enlarged bases. 



LEAF-SCARS Opposite, broadly U-shaped, nearly encircle stem; adjacent edges form rather 

 blunt teeth which are separated by a ridge. Bundle-scars usually 3, often subdivided into 5-8. 



FLOWERS Appear in May or June after the leaves are full grown in drooping terminal 

 racemes. Staminate and pistillate flowers occur on same plant but in different clusters. 



FRUIT Matures in September in drooping racemes; wings of the keys, thin, very divergent, 

 about J of an inch long, marked on one side of seed with a depression. 



WOOD Diffuse-porous; soft, close-grained, light brown with wide zone of sapwood. Seldom 

 used commercially. Weighs 33.02 Ibs. per cubic foot. 



DISTINGUISHING CHARACTERISTICS The Striped Maple, also known as Moosewood and 

 Whistlewood, can be readily distinguished at all seasons of the year by the light longitudinal 

 streaks on the branches and trunk. They often appear the second year and persist for 

 many years on the trunk. In winter the large, evidently-stalked, valvate, and red buds 

 together with the smooth branches and brown pith are characteristic. In summer the drooping 

 raceme of flowers and the goose-foot-like leaves with their finely serrate margins and rusty 

 pubescence on the lower surface are distinctive. 



RANGE From Nova Scotia west to Minnesota, south especially along the mountains to 

 Georgia. 



DISTRIBUTION IN PENNSYLVANIA Rather common locally in the mountainous parts of 

 the State especially on shaded slopes and in deep ravines. Very common in Mifflin, Centre, 

 Blair, and Huntingdon counties. 



HABITAT It prefers moist, cool, shaded, often rocky mountain slopes. 



IMPORTANCE OF THE SPECIES The wood is of practically no commercial value. The 

 chief value of the tree is its attractive ornamental qualities both as an individual tree and as 

 a component of the understory of the forest structure. 



