CHARACTERISTICS OF THE TREE: Height, 50'-90', even 120'; diameter, 3'-5'; form suggests elm; bark, reddish brown, furrowed, surface separating into large, loose scales; leaves, palmately 5 lobed, with narrow, acute sinuses, silvery white beneath, turn only yellow in autumn; fruit, divergent, winged samaras. APPEARANCE OF WOOD: Color, brown and reddish, sap-wood, cream; diffuse-porous; rings, obscure; grain, twisted, wavy, fine, polishes well; rays, thin, numerous. PHYSICAL QUALITIES: Weight, medium (40th in this list); 32 lbs. per cu. ft.; sp. gr., 0.5269; very strong (19th in this list); very elastic (20th in this list); hard (25th in this list); shrinkage, 5 per cent.; warps, ............; not durable under exposure; easily worked; splits in nailing. COMMON USES: Flooring, furniture, turnery, wooden ware. REMARKS: Grows rapidly. Curly varieties found. Sap produces some sugar. [Illustration: Radial Section, life size.] [Illustration: Cross-section, magnified 37-1/2 diameters.] [Illustration: Tangential Section, life size.] 59 RED MAPLE. _Acer rubrum_ Linnaeus. _Acer_, the classical Latin name; _rubrum_, refers to red flowers and autumn leaves. [Illustration: Habitat.] HABITAT: (See map); best in lower Ohio valley. [Illustration: Leaf.] CHARACTERISTICS OF THE TREE: Height, 80'-120'; diameter, 2'-4'; branches, low; bark, dark gray, shaggy, divided by long ridges; leaves, palmately 5 lobed, acute sinuses; fruit, double samaras, forming characteristic maple key. APPEARANCE OF WOOD: Color, light reddish brown, sap-wood, lighter; diffuse-porous; rings, obscure; grain, crooked; rays, numerous, obscure. PHYSICAL QUALITIES: Weight, medium (30th in this list); 38 lbs. per cu. ft.; sp. gr., 0.6178; strong (36th in this list); elastic (36th in this list); hard (27th in this list); shrinkage, 5 per cent.; warps .......; not durable; fairly hard to work; splits with difficulty, splits badly in nailing. COMMON USES: Flooring, turning, wooden ware. REMARKS: Grows rapidly. Has red flowers, red keys, red leaf stems, and leaves scarlet or crimson in autumn. [Illustration: Radial Section, life size.] [Illustration: Cross-section, magnified 37-1/2 diameters.] [Illustration: Tangential Section, life size.] 60 HARD MAPLE. SUGAR MAPLE. ROCK MAPLE. _Acer saccharum_ Marshall. _Acer_, the classical Latin name; _saccharum_, refers to sweet sap. [Illustration: Habitat.] HABITAT: (See map); best in regions of Great Lakes. [Illustration: Leaf.] CHARACTERISTICS OF THE TREE: Height, 100'-120'; diameter, 1-1/2'-3', even 4'; often trees in forest are without branches for 60'-70' from ground, in the open, large impressive tree; bark, gray brown, thick, deep, longitudinal fissures, hard and rough; leaves, opposite, 3 to 5 lobed, scarlet and yellow in autumn; fruit, double, slightly divergent samaras.