The Sitka Spruce (Picea sitchensis) is a large coniferous evergreen tree growing to 50-70 m tall, exceptionally to 90 m tall, and with a trunk diameter of up to 5 m. It is by far the largest species of spruce, and the third tallest conifer species in the world (after Coast Redwood and Coast Douglas-fir). It acquires its name from the community of Sitka, Alaska.
The cones are pendulous, slender cylindrical, 5-11 cm long and 2 cm broad when closed, opening to 3 cm broad. They have thin, flexible scales 15-20 mm long; the bracts just above the scales are the longest of any spruce, occasionally just exserted and visible on the closed cones. They are green or reddish, maturing pale brown 5-7 months after pollination. The seeds are black, 3 mm long, with a slender, 7-9 mm long pale brown wing.
Sitka Spruce is native to the west coast of North America, with its northwestern limit on Kodiak Island, Alaska, and its southeastern limit near Fort Bragg in northern California (Griffin & Critchfield 1972). It is closely associated with the temperate rain forests and is found within a few kilometers of the coast in the southern portion of its range. North of Oregon, its range extends inland along river floodplains, but nowhere does its range extend more than 80 km from the Pacific Ocean and its inlets.
More than a century of logging has left only a remnant of the spruce forest. The largest trees were cut long before careful measurements could be made. Trees over 90 m tall may still be seen in the Pacific Rim National Park on Vancouver Island, British Columbia (the Carmanah Giant, at tall the tallest tree in Canada), and in the Olympic National Park, Washington and Prairie Creek Redwoods State Park, California (USA); two at the last site are just over tall. The Queets Spruce is the largest in the world with a trunk volume of . It is located near the Queets River in Olympic National Park, about from the Pacific Ocean. The fourth-largest tree, known as the Seaside Spruce or the Klootchy Creek Giant, with a height of and a volume of blew down on December 2, 2007 during a windstorm, reducing it to tall. This was not unexpected as the tree had been hit by lightning and damaged in previous storms. The Quinault Lake Spruce (pictured left) is the third largest in the world with a wood volume of . It is located near the eastern tip of Lake Quinault north of Aberdeen, Washington, about from the Pacific Ocean.
Sitka Spruce is a long-lived tree, with individuals over 700 years old known. Because it grows rapidly under favorable conditions, large size may not indicate exceptional age. The Queets Spruce has been estimated to be only 350 to 450 years old, but adds more than a cubic meter of wood each year (Van Pelt, 2001).
A unique specimen with golden foliage that used to grow on the Queen Charlotte Islands, known as Kiidk'yaas, is sacred to the Haida Native American people. It was illegally felled, although saplings grown from cuttings can now be found near its original site.
