CHARACTERISTICS OF THE TREE: Height, 75'-100'; diameter, 3'-4', and even 12'; branches, low; bark, thick, shallow, irregular, fissures, broad, grayish brown ridges; leaves, lanceolate, coarsely serrate, midribs and veins prominent; fruit, nuts, thin-shelled, sweet, enclosed in prickly burrs. APPEARANCE OF WOOD: Color, reddish brown, sap-wood lighter; ring-porous; rings, plain, pores large; grain, straight; rays, numerous, obscure. PHYSICAL QUALITIES: Weight, light (50th in this list); 28 lbs. per cu. ft.; sp. gr., 0.4504; medium strong (46th in this list); elasticity, medium (46th in this list); medium hard (44th in this list); shrinkage, 6 per cent.; warps badly; very durable, especially in contact with soil, fairly easy to plane, chisel and saw; splits easily. COMMON USES: Railway ties, fence posts, interior finish. REMARKS: Grows rapidly, and lives to great age. Wood contains much tannic acid. Uses depend largely upon its durability. Lately whole regions depleted by fungous pest. [Illustration: Radial Section, life size.] [Illustration: Cross-section, magnified 37-1/2 diameters.] [Illustration: Tangential Section, life size.] 41 RED OAK. _Quercus rubra_ Linnaeus. _Quercus_, the classical Latin name; _rubra_, refers to red color of wood. [Illustration: Habitat.] HABITAT: (See map); best in Massachusetts and north of the Ohio river. [Illustration: Leaf.] CHARACTERISTICS OF THE TREE: Height, 70'-100', even 150'; diameter, 3'-6'; a tall, handsome tree, branches rather low; bark, brownish gray, broad, thin, rounded ridges, rather smooth; leaves, 7 to 9 triangular pointed lobes, with rounded sinuses; acorns, characteristically large, in flat shallow cups. APPEARANCE OF WOOD: Color, reddish brown, sap-wood darker; ring-porous; rings, marked by several rows of very large open ducts; grain, crooked, coarse; rays, few, but broad, conspicuous. PHYSICAL QUALITIES: Heavy (23d in this list); 45 lbs. per cu. ft.; sp. gr., 0.6540; strong (21st in this list); elastic (18th in this list); hard (26th in this list); shrinkage 6 to 10 per cent.; warps and checks badly; moderately durable; easier to work than white oak; splits readily, nails badly. COMMON USES: Cooperage, interior finish, furniture. REMARKS: Grows rapidly. An inferior substitute for white oak. Bark used in tanning. [Illustration: Radial Section, life size.] [Illustration: Cross-section, magnified 37-1/2 diameters.] [Illustration: Tangential Section, life size.] 42 BLACK OAK. YELLOW BARK OAK. Black refers to color of outer bark; yellow bark, refers to the inner bark, which is orange yellow. _Quercus velutina_ Lamarck. _Quercus tinctoria_ Michaux. _Quercus_, the classical Latin name; _velutina_, refers to the velvety surface of the young leaf; _tinctoria_, refers to dye obtained from inner bark. [Illustration: Habitat.] HABITAT: (See map); best in lower Ohio valley. [Illustration: Leaf.]