The mature Alaska Sitka Spruce trees in the southeast Alaska forest average nearly 160 feet high and 5 feet in diameter, but trees with heights of 200 feet and diameters of up to 8 feet are common. Sitka Spruce has many characteristics that make it an excellent choice for many building applications. It has a very high strength-to-weight ratio and is extremely resilient, with excellent shock absorbing qualities. It holds fasteners securely and has the ability to withstand sharp impacts and suddenly applied loads.

These fine attributes make it the #1 sought after wood for light aircraft construction and other specialized applications such as masts, spars, wind tunnel propellers, and fine cabinets The wood is easily worked and has little tendency to split or splinter. It is considered even grained and soft textured. It is also easy to kiln dry, and shrinks and swells moderately. Aesthetically, the heartwood of the Sitka Spruce is a very light silvery color, almost white, which blends gradually into a very creamy sapwood. When planed, the surface of the wood has a beautiful silky sheen.

Alaska Sitka Spruce is the ideal species for manufacturing large, appearance grade, structural timbers. Because the timbers are cut from large, straight grained logs, they generally remain straight as they season, especially if dried in the Radio Frequency Vacuum "RFV" kilns (please refer to the Custom Milling section for more information on RFV Kiln drying.).

Arc can produce RFV kiln dried timbers as large as 42" x 42" and up to 50 feet long. These timbers are available in the highest grades. The largest timbers provided by Arc have been in the Alaska Sitka Spruce beams. These timbers have been remanufactured into exquisite truss packages and have been called "furniture-grade" timbers by builders and architects.

Alaska Sitka Spruce's high percentage of heartwood within the log makes it popular for bevel or colonial siding. As siding, Sitka Spruce does not warp or twist before or after installation. Its even grained and soft texture permits nailing without splitting. The excellent paint holding quality of Sitka Spruce siding is due in part to its non-pitchy character. Its light, uniform color is one of the reasons this siding requires fewer coats of paint.

Like Alaska Hemlock, the lower branches of Alaska Sitka Spruce die and fall away because of competition for sunlight. Thus, as the tree grows, it "prunes" itself and develops clear trunks up to three-quarters of its height. This natural characteristic is highly desirable in softwoods, as it leads to increased volumes of clear lumber in large logs. Old growth Alaska Sitka Spruce logs produce some of the finest Clear Vertical grain material in the world. Sitka Spruce is also used extensively as sounding boards, and sounding board ribs in the finest of pianos, guitars and other stringed instruments.

UNIQUE "ALASKAN" DESIGN VALUES:
Due to the unique growing season and weather patterns within the temperate rain forest of southeast Alaska, new design values of a higher structural grade have been created for the species of timber that grow solely in southeast Alaska. As a result of the work conducted by the Ketchikan Wood Technology Center (KWTC) and Western Wood Products Association (WWPA), Alaska Sitka Spruce has been recognized as a unique species by the American Lumber Standards Committee. These new design values reveal that the Sitka Spruce indigenous to southeast Alaska have a much higher strength and stiffness than the Sitka Spruce in British Colombia, Washington and Oregon. Please click on the link below to download the Design Values and Spans for Alaskan Species Lumber (WWPA Tech Note 2005).

Grading Agencies

1. Standard Grading Rules for West Coast Lumber; published by the West Coast Lumber Inspection Bureau (WCLIB); Box 23145, Portland, OR 97281-3145; 503.639.0651; 503.684.8928 (fax); e-mail info@wclib.org 2. Western Lumber Grading Rules; published by Western Wood Products Association (WWPA); Yeon Building, 522 SW Fifth Avenue, Portland Oregon 97204-2122; 503.224.3930; 503.224.3934 (fax); e-mail info@wwpa.org 3. Standard Grading Rules for Canadian Lumber; published by the National Lumber Grades Authority (NLGA); 406 First Capital Place, 960 Quayside Drive, New Westminster, BC V3M 6G2; 604.524.2393; 604.524.2893; e-mail info@nlga.org

	Alaskan Species Lumber Design Values (2005)
	Sitka Spruce Growth Ring Averages