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SILVER MAPLE. 

 Acer saccharinum, Linnaeus. 



FORM — Usually a tree about 50-60 ft. in height but may attain a maximum height of 120 

 ft. with a diameter of 4* feet. Trunk short and divides into lateral branches which again 

 freely subdivide and form a broad head. Lateral branches have pronounced droop, and 

 distinct upward curve at the end. 



BARK — On branches and young trunks smooth and gray; on old trunks brown with a some 

 what furrowed surface separating into thin flakes which are fastened at the center and loose 

 at both ends. 



TWIGS — Somewhat slender, glossy, at first green, later bright chestnut-brown, covered 

 with numerous light lenticels. 



BUDS — Opposite, red, obtuse-pointed, sessile or short-stalked; flower buds stout, spherical, 

 accessory, covered with overlapping scales, 6-3 of which may be exposed. Margin of scales 

 ciliated and often light in color. 



LEAVES — Opposite, simple, 5-lobed, coarsoly toothed; bright green on upper surface and 

 silvery -white on lower; with deep round-based sinuses. 



LEAF-SCARS — Opposite, U-shaped to V-shaped, not encircling stem. Bundle-scars 3, in a 

 lunate line. 



FLOWERS — Appear in March or April before the leaves are out, in dense, sessile, axillary 

 clusters. Staininate and pistillate occur in separate clusters sometimes on the same, some- 

 times on different trees. Petals absent. 



FRUIT — Matures about May; clustered along branchlets, borne on slender drooping stalks; 

 wings of the keys usually from 1-2 inches long, divergent, sometimes straight, or curved. 



WOOD — DiflFuse-porous; moderately hard, rather brittle, close-grained, with wide sapwood. 

 Used for flooring, cheap furniture, and paper pulp. Weighs 32.84 lbs. per cubic foot. 



DISTINGUISHING CHARACTERISTICS— The Silver Maple, also known as White Maple, 

 River Maple, and Soft Maple, can be recognized in summer by its leaves with a silvery-white 

 lower surface and deep round-based sinuses. In winter it closely resembles the Red Maple 

 but may bo distinguished from it by the pungent odor of the broken twigs and the bright 

 chestnut-brown twigs. The bark of the Silver Maple is somewhat furrowed and separates into 

 thin flakes which are loose at both ends and fastened in the middle. The lateral branches have 

 a pronounced droop and a distinct upward curve at the ends. This may sometimes be a dis- 

 tinctive character. The Red Maple and the Silver Maple are distinguished from all the other 

 Maples of the State by the numerous, round, red, collateral buds. 



RANGE — New Brunswick to southern Ontario, south to Florida and Indian Territory. 



DISTRIBUTION IN PENNSYLVANIA — Occasional and local throughout the State, especially 

 along larger streams. 



HABITAT — It prefers a moist deep soil such as is found along stream banks. It will exist 

 in drier locations but cot attain a large size. 



IMPORTANCE OF THE SPFCIES— The Silver Maple is a very attractive ornamental tree. A 

 few special ornamental varieties have been developed. The wood is brittle and consequently 

 the branches are apt to be broken off during a storm. This defect somewhat checks the 

 planting of this species in exposed places. It is a rapid grower. The wood which it produces 

 is of no special commercial importance and consequently it has little to recommend it for 

 forestry purposes, except that it forms an excellent soil cover in the under-story of the forest. 



