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Two major spruces are found in the western forests of the U.S. Engelmann spruce (Picea engelmannii) is found throughout the Rocky Mountains, from Alberta to Arizona. It is named after George Englemann who discovered this species in the mid 1800s. Sitka spruce is found primarily within 50 miles of the Pacific Coast from Alaska to northern California. The name comes from Sitka Island where the tree was discovered in 1892; Sitka spruce is also the state tree of Alaska.

Spruce trees are one of the largest trees in the western forests, often reaching 175 feet in height and 3 to 6 feet in diameter. They may live 700 years. A record sized tree in Oregon is nearly 17 feet in diameter and over 215 feet high.

For their weight, the spruces are exceptionally strong.  Hence, spruce has been used for airplanes, including propellers, where high strength was required, but weight needed to be as low as possible. (Note: Howard Hughes’ “Spruce Goose” airplane was notmadeofspruce, but used primarily birch.) 

Thin panels of Sitka spruce are noted for their very good sound resonance.  Hence, they are preferred for quality piano sounding boards. Spruce is also used for other stringed instruments, such as guitars. Other uses for spruce include furniture, millwork, cabinets, sailing ship masts and other components,andcooperage. Often these spruces are mixed in with true firs or other softwoods species and are not sold separately.
 

Processing suggestions and characteristics

(The wood from these two trees is nearly identical in processing and properties; Englemann is slightly lighter weight and slightly weaker. Data below is for Sitka.)

Density.
Sitka spruce weighs about 27 pounds per cubic foot. A piece of 1 x 6 x 12′ lumber (actual size (3/4″ x 5-1/2″ x 12′) will weigh about 9 pounds at 9 percent MC.

Drying.
In general, spruce dries very easily. It is important that lumber intended for remanufacturing not be over-dried (dried under 9 percent MC) or the wood can become too brittle when machining.  Shrinkage in drying is 3 percent (quartersawn) to 6 percent (flatsawn).

Gluing and Machining.
Gluing is excellent. Dry wood does absorb glue quickly, so adequate spread rates are required to prevent a starved joint.

Machining is excellent if tools are sharp and any machine pressures are not high. Chipped grain is common when machining close to a knot.

Stability.
Spruce is fairly stable, requiring about 4 percent MC change to have a size change of 1% (tangential direction or the width of flatsawn lumber).  For quartersawn lumber, a 7 percent MC change will cause a 1 percent width change (radial direction).

Strength.
Spruceisan moderately strong wood for its size, but for its weight is very strong. The strength (MOR) is 10,200 psi; stiffness is 1.57 million psi; and hardness is 510 pounds.  (Eastern white pine values are 8600 psi, 1.24 million psi and 380 pounds. Spruce is only 14 percent heavier than EWP, yet is 20 percent stronger, 25 percent stiffer and 34 percent harder.)

Compared to hardwoods, spruce needs slightly larger fasteners (including head size) to obtain higher fastening power.

Color and Grain.
The sapwood is creamy white, but the heartwood is pinkish yellow, becoming somewhat darker with exposure to light. Lumber can all sapwood, all heartwood or mixed.

The grain is very fine and straight.

Some people report skin allergies from contact with the wood, especially the fine dust.

Longleaf pine (Pinus palustris), also called fat pine or heart pine, is one of the four major species making up the Southern pines. It is the strongest of the four, the tallest (over 100 feet) and the most fire resistant.

While the tall, stately longleaf pine once covered 30 to 60 million acres of the southeastern U. S. coastal plain, 200 years of logging and land clearing have greatly reduced its range to 10 percent of the past acreage. The tree takes 100 to 150 years to become full sized and may live for 300 years. Needles are 8 to 18 inches long. Pine cones are 6 to 10 inches long.

A great deal of effort is being placed on protecting younger trees so there will be a supply of older trees in the future for the endangered red-cockaded woodpecker who uses the mature trees for nesting. The seeds are an excellent food source for squirrels, turkey, quail and brown-headed nuthatches.

Longleaf pines were a major resource for naval stores in the past (that is, resin or pitch before petroleum-based tars and derivatives were available). The timber was also used for heavy construction, railroad bridges and elevated tracks, floors and cooperage (barrels).

Present uses include floors and large lumber pieces and timbers, especially historical conservation and restoration, as well as typical construction uses. Some longleaf pine lumber and timbers have been salvaged from torn down old buildings and some logs from the bottom of lakes and rivers. There is very limited harvesting of old growth longleaf pine today.

Processing suggestions and characteristics

Density
The density of longleaf pine at 12% MC is 37 pounds per cubic foot.  This means that a kiln-dried 2x10x16 piece of lumber will weigh over 42 pounds.  Loblolly pine, a common Southern pine, weighs 34 pounds per cubic foot.  Eastern white pine weighs 24 pounds per cubic foot.
 

Drying
Longleaf pine dries very easily and rapidly.  Shrinkage in drying to 10% MC is 5.2% tangentially (the width of flatsawn lumber) and 3.4% radially (the width of quartersawn).  Drying temperatures should exceed 180 degrees for at least 24 hours to assure that the pitch is set so that the sap will not exude out when the wood is in-use.

Gluing and Machining
Gluing is difficult, in part due to the high resin content of the wood and in part due to the high density.  It is suggested that the surface be freshly prepared and washed with a solvent to enhance gluing.

This wood is quite hard to machine due to its high density.  Like all southern pines, it is common to have the hard, dense part of the growth ring pushed down into the softer fibers when planing, rather than cut cleanly.  When the wood is then exposed to any moisture regain, the crushed fibers return to their original size and thereby push the dense fibers above the surface, causing a defect called raised grain.  As with all dense wood, the tools must be very sharp.

Although the aroma of freshly processed wood is quite pleasant, the fine dry dust may cause dermatitis, allergic bronchial asthma, or rhinitis in some individuals. 

Stability
The wood is fairly stable in use.  It requires a 4% MC change to result in a 1% size change tangentially and 6% MC change radially.

Strength
The ultimate strength (MOR) is14,500 psi.  The bendability (MOE) is 1.98 million psi.  The surface hardness is 870 pounds.  Comparable values for loblolly are 12,800 psi, 1.79 millionpsiand 690 pounds; for eastern white pine, 8600 psi, 1.2 million psi, 380 pounds.

Color and Grain.
The older trees produce lumber that us almost100% reddish heartwood.  The second growth trees may have 2″ wide yellowish-colored sapwood. The color contrast within an individual growth ring is high between the earlywood (light colored) and latewood (dark colored), adding character.  The grain is fairly straight, except around knots and when compression wood is present.