The Softwood Strong Enough To Fly

In the days when Russia claimed Baranof Island, off the coast of present-day Alaska, stands of spruce trees towered over it like 300'-tall sentinels. Botanist August Bongard was so impressed by these trees when he traveled there in the early 1800s that he named them Sitka, after the island's Russian capital.

Sitka spruce, so hardy that it grows farther north than any other conifer, also rates as the "strongman" of soft woods. Indians long ago used its tough root tendrils to sew together their bark canoes.

In modern times, Sitka spruce, with reputedly the greatest strength-to-weight ratio of any wood, took to the air. The famous Spruce Goose amphibious airplane, built by millionaire entrepreneur Howard Hughes in the '40s, was made from this wood. So were the frames of some English WWII fighter planes. In air battles they were so small and fast they earned the name "mosquitoes."

Boatbuilders have always found Sitka spruce well suited for masts and oars, and lutheirs love it for the soundboards of stringed instruments. However, much of this wood becomes millwork, or is made into furniture, boxes, and crates. Even larger quantities end up as paper pulp because of the wood's long fibers.

Often called coast spruce and yellow spruce, Sitka spruce (Picea sitchensis) stands taller than any of the 18 spruce species found in the Northern Hemisphere. It grows in a coastal area about 50 miles wide and stretching some 2,000 miles from northern California to Kodiak Island, Alaska. It prefers low, wet valleys where the trees grow in dense stands and have no branches for the first 40' or more.

You'll be able to identify sitka spruce by its size; the scaley, deep reddish-brown or purple bark; and its needles. Unique for a spruce, the needles of Sitka spruce grow flat, sharply pointed, and a bright bluish green. Flexible cones up to 4" long develop over the summer, finally opening to drop their seeds in the fall. Where the seeds land on moist ground, they readily germinate and grow.

The color of Sitka spruce wood ranges from nearly white to pink to light brown, and sometimes has a candy-stripe look. Heartwood tends to run slightly darker.

Very straight-grained, Sitka spruce has less conspicuous growth rings than pine. It's also about 10 percent lighter, weighing 25 lbs. per cubic foot air-dry.

In the shop, you'll find that it works easily with both hand and power tools. It nails, screws, and glues well, and takes a lustrous finish. However, because Sitka spruce is tough and stringy, bandsawing requires sharp, wide blades.

Sitka spruce imparts no taste or gives off no odor, so use it for food canisters, boxes, and butter molds. Its strength and lightness make it perfect for painted furniture and shelving, as well as moldings and doors.

Quarter-sawn so the grain runs vertically, this wood becomes a top choice for the sound boards of guitars, dulcimers, and other stringed instruments. It flexes to aid sound.

On the West Coast and in the western states, you can buy Sitka spruce at lumberyards. Elsewhere, you have to special-order it, even in thin-cut sound-board stock from specialty suppliers. A top-grade soundboard will cost from $35 to $50. But the price of construction grade Sitka spruce approaches that of pine. Specially sawn, vertical grain lumber may cost $3 a board foot.

Illustration:Steve SchindlerPhotographs:Hopkins Associates