194 



SUGAR MAPLE. 



Acer saccharum, Marshall. 



FORM A large timber tree attaining a maximum height of 120 ft. with a diameter of 5 feet. 

 Open grown trees have short trunks bearing stout, rather erect branches which form a 

 spreading, egg-shaped, often round-topped crown. Trees in closed stands have long, straight, 

 clean trunks bearing shallow, round crowns with large limbs. 



BARK On branches and young trunks .smooth and light brown; on older trunks brown, 

 deeply channelled into long irregular plates or flakes which often loosen vertically along 

 the side. See Fig. 62. 



TWIGS Slender, smooth, reddish-brown to orange-brown, covered with numerous pale lenti- 

 cels. 



BUDS Opposite, brown, sharp-pointed, conical, hairy at apex; terminal bud about twice as 

 long as appressed lateral ones; covered by overlapping scales, with from 8-16 of them exposed. 



LEAVES Opposite, simple, usually 5-lobed, with a sparsely toothed margin and round- 

 based sinuses, cordate at base, thin in texture, 8-5 inches long and greater in width. Mature 

 leaves are bright green above and pale green beiow. 



LEAF-SCARS Opposite, V-shaped to U-shaped, nearly encircling stem. Bundle-scars usually 

 3, in a lunate line. 



FLOWERS Appear in April and May with the leaves, in drooping corymbs both from the 

 terminal mixed buds and the lateral propagative buds. The staminate and pistillate occur 

 in different clusters. 



FRUIT Matures about September; clustered, borne on drooping stalks; wings of the keys 

 about i-1 inch long, parallel, or slightly divergent. 



WOOD Diffuse-porous; heavy, hard, olose-grained, with fine surface, light brown to reddish. 

 Used for Interior finish, furniture, shoe lasts, railroad ties. Abnormal 'modifications of the 

 structure of the wood known as Curly Maple and Bird's Eye Maple are rather common and 

 especially prized in cabinet making. Weighs 43.0S Ibs. per cubic foot 



DISTINGUISHING CHARACTERISTICS The Sugar Maple, also known as Hard Maple and 

 Rock Maple, can be distinguished in summer from the other Maples by its large, simple 

 leaves which are thin in texture and have their lobes coarsely toothed. The flowers appear 

 with the leaves while those of the Red Maple and the Silver Maple appear before, and those 

 of the Mountain Maple and the Striped Maple after the leaves. The fruit clusters of the 

 Sugar Maple are usually developed from terminal buds while those of the Red Maple and 

 Silver Maple are developed from lateral buds. The fruit of the Sugar Maple does not mature 

 until September and may often persist into the winter while the fruit of the Red Maple and 

 Silver Maple matures in early summer and germinates at once after falling upon the ground. 

 In winter the Sugar Maple can be recognized by its conical, sharp-pointed, brown buds with 

 from 8-16 exposed and overlapping scales, and by the slender brown twigs marked with pale 

 lenticels. The rough furrowed trunk is also characteristic of older trees. 



' RANGE Newfoundland to Manitoba, south to Florida and Texas. 



DISTRIBUTION IN PENNSYLVANIA Common , especially in the northern and eastern parts 

 of the State. It is possibly, next to Chestnut, the commonest tree in this State. 



HABITAT It flourishes best on well drained rich soil, but will thrive even when the soil 

 is not rich. It is common on low ridges at the base of mountains, and along slopes. It 

 reaches its best development in central New England, New York, northern Pennsylvania, 

 and the Lake States. 



IMPORTANCE OF THE SPECIES The Sugar Maple is a valuable timber tree. Its im- 

 portance is being realized more as its wood finds new uses. The process of timber impregna- 

 tion has raised the value of the wood of this species. It is not only valuable as a timber 

 tree but produces annually .n large quantity of maple sugar and maple syrup, and in addition 

 is one of our most attractive ornamental trees. 



