MOUNT RAINIER The Forests of Mount Rainier National Park

SITKA SPRUCE (PICEA SITCHENSIS)

Along the coast from Oregon to Alaska the heavy rainfall, dense fog, and equable climate are favorable to the growth of the Sitka or tideland spruce. About tidewater and for 30 miles inland it forms dense stands. The largest trees are over 200 feet high and their trunks, buttressed and swelled at the base, are sometimes 8 feet in diameter. It is most common and reaches its greatest development not far from the ocean beach, but extends up the stream valleys, and fair-sized trees are scattered through the river bottoms of the Carbon and White Rivers in the park. Small trees, stunted by the cold and bearing little resemblance to the big spruce characteristic of the forest at sea level, are found on the ridge between the Winthrop and Carbon Glaciers at an altitude of 6,000 feet. In the Nisqually Valley a few trees grow in the river bottom. On Rampart Ridge at an elevation of 4,900 feet, near Longmire Springs, a solitary individual stands surrounded by alpine and lively fir, mountain hemlock, Alaska cedar, and western white pine.

Fig. 15.—Sitka spruce (Picea sitchensis).

Where the Sitka spruce grows in dense forests the trunk tapers gradually from the base and is usually free from limbs for 50 feet. In more open situations the trunk tapers rapidly, and the pendant branches form a loose pyramidal crown, pointed at the top, broad and reaching nearly to the ground at the bottom. The leaves have sharp, stiff points, the prickly feeling of which when touched readily distinguishes the spruce from other evergreens.

The sapwood is white. The heartwood has a slight reddish tinge. It is stiff, free from knots, straight grained, very light, and moderately strong. It is particularly valuable for airplane stock and other purposes where the weight must be reduced to the minimum. It is used for packing boxes, boat building, interior-finish, oars, and the tops of musical instruments. The inferior grades are sold for general building purposes. On account of its rapid growth and because so large a proportion of the wood is clear grained and free from pitch and defect, the Sitka or tideland spruce is a valuable lumber tree. The best stands of clear, large spruce occur on the Olympic Peninsula.