Part 11 (1/2)

APPEARANCE OF WOOD: Heart-wood, spring wood light yellow, summer wood, red brown; sap wood, lighter; non-porous; rings, very plain and strongly marked; grain, straight; rays, numerous, conspicuous; very resinous, but resin ducts few and not large.

PHYSICAL QUALITIES: Heavy (18th in this list); 38 lbs. per cu. ft.; sp. gr. 0.6999; very strong (7th in this list); very elastic (4th in this list); hardness, medium (33d in this list); shrinkage, 4 per cent.; warps very little; quite durable; works hard, tough; splits badly in nailing.

COMMON USES: Joists, beams, bridge and building trusses, interior finish, s.h.i.+p building, and general construction work.

REMARKS: Almost exclusively the source of turpentine, tar, pitch and resin in the United States. Known in the English market as pitch pine.

[Ill.u.s.tration: Radial Section, life size.]

[Ill.u.s.tration: Cross-section, magnified 37-1/2 diameters.]

[Ill.u.s.tration: Tangential Section, life size.]

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SHORT-LEAF PINE. YELLOW PINE.

_Pinus echinata_ Miller.

_Pinus_, the cla.s.sical Latin name; _echinata_ refers to spiny cones.

[Ill.u.s.tration: Habitat.]

HABITAT: (See map); best in lower Mississippi basin.

[Ill.u.s.tration: Leaf.]

CHARACTERISTICS OF THE TREE: Straight, tall trunk, sometimes 100'

high; branches high; diameter 2'-4'; bark, pale grayish red-brown, fissures, running helter-skelter, making large irregular plates, covered with small scales; leaves in twos, 3” long; cones small.

APPEARANCE OF WOOD: Color, heartwood, summer wood, red, spring-wood, yellow; sap-wood, lighter; non-porous; annual rings very plain, sharp contrast between spring and summer wood; grain, straight, coa.r.s.e; rays, numerous, conspicuous; very resinous, ducts large and many.

PHYSICAL QUALITIES: Weight, medium (32nd in this list); 32 lbs.

per cu. ft.; sp. gr., 0.6104; very strong (18th in this list); very elastic (8th in this list); soft (38th in this list); shrinkage, 4 per cent.; warps little; durable; troublesome to work; likely to split along annual rings in nailing.

COMMON USES: Heavy construction, railroad ties, house trim, s.h.i.+p building, cars, docks, bridges.

REMARKS: Wood hardly distinguishable from long-leaf pine. Often forms pure forests. The most desirable yellow pine, much less resinous and more easily worked than others.

[Ill.u.s.tration: Radial Section, life size.]

[Ill.u.s.tration: Cross-section, magnified 37-1/2 diameters.]

[Ill.u.s.tration: Tangential Section, life size.]

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