Sitka Spruce

(Picea sitchensis)

Color Photographs: © Nearctica.com, Inc.

Color Photographs: © by and courtesy of Charles Webber, California Academy of Sciences

Sitka Spruce (Picea sitchensis)

Identifying Characters: The flattened needles, brown cones, and Pacific Northwest coastal distribution will usually identify Sitka Spruce.

Similar Species: The flattened needles with separate this species from both Engelmann Spruce and White Spruce. Brewer Spruce has flattened needles, but the cones are purple and the apices of the cone scales are evenly rounded, not elongate.

Measurements: Sitka Spruce is the tallest spruce species in the world; average height of mature individuals is 90 to 150 feet, although individuals well over 200 feet have been reported; diameter at breast height is 3 to 5 feet.

Cones: Cones 2 to 3.5 inches long, elongate and cylindrical, tapering at the apex; short stalked, light orange to orange-brown at maturity; cone scales elongate, thin but stiff; apex of cone scale truncate and irregularly toothed.

Needles: Needles arranged regularly about the twig, 0.5 to 1 inch in length; needles flattened with a slight ridge; color dark green.

Bark: Gray, thin, smooth, broken into irregular scaly plates.

Native Range: Sitka Spruce grows in a narrow strip along the north Pacific coast from latitude 61° N. in southcentral Alaska to 39° N. in northern California. The most extensive portion of the range in both width and elevation is in southeast Alaska and northern British Columbia, where the east-west range extends for about 210 km (130 mi) to include a narrow mainland strip and the many islands of the Alexander Archipelago in Alaska and the Queen Charlotte Islands in British Columbia. North and west of southeast Alaska, along the Gulf of Alaska to Prince William Sound, the range is restricted by steep mountains and piedmont glaciers edging the sea. Within Prince William Sound, the range again widens to about 105 km (65 mi) to include many offshore islands. Westward, the range again narrows. It extends across Cook Inlet to Cape Kubugakli and across Shelikof Strait to the islands of the Kodiak Archipelago where the range continues to advance to the southwest.

In southern British Columbia, the range includes a narrow mainland strip and offshore islands, but the best development occurs on the northern tip and west side of Vancouver Island. On the east side of Vancouver Island and on the mainland south to Washington, the range tends to be restricted to sea-facing slopes and valley bottoms.

In Washington, the range includes a narrow mainland strip along the Strait of Georgia, around Puget Sound, up valleys to the east, and on the Olympic Peninsula. On the west side of the Olympic Peninsula, the range broadens to include the extensive coastal plain and seaward mountain slopes. It narrows southward along the Washington and Oregon coast but extends inland for several kilometers along the major rivers. In northern California, the range is more attenuated and becomes discontinuous. A disjunct population in Mendocino County, California, marks the southern limit of the range. (Silvics of North America. 1990. Agriculture Handbook 654.)

Habitat: Sitka Spruces is restricted to the coastal region of the Pacific Northwest. It occurs in the fog regions of the coastal forests, primarily in pure stands or with Western Hemlock.