Scientific name: Picea sitchensis (Bongard) Carrière 1855

Synonyms: Abies falcata Raf., Abies menziesii (Douglas ex D.Don) Lindl., Abies merkiana Fisch. ex Parl., Abies sitchensis (Bong.) Lindl. & Gordon, Abies trigona Raf., Picea falcata (Raf.) J.V.Suringar, Picea grandis Gordon, Picea menziesii (Douglas ex D.Don) Carrière, Pinus menziesii Douglas ex D.Don, Pinus sitchensis Bong., Sequoia rafinesquei Carrière

Common names: Sitka spruce, Tideland spruce

Description

Tree to 70(-95) m tall or dwarfed and shrublike on high barren outcrops, with trunk to 5(-6.5) m in diameter, often further flared and buttressed at the base. Bark gray, remaining relatively smooth and scaly even on the largest trees. Crown narrowly cylindrical, with relatively slender, horizontal branches drooping at the tips and bearing stiffly horizontal to hanging side branches, the lowest branches sometimes rooting to start new trees. New branchlets very pale pinkish brown, hairless. Buds (4-)5-10 mm long, generally not resinous. Needles dark green to yellowish green above, bluish green beneath with wax, (1-)1.5-2.5(-3) cm long, curved slightly forward, flattened diamond-shaped, without or with one to three incomplete lines of stomates on the two outer faces and with three to five lines in the stomatal bands on the two inner faces, stiff and prickly. Pollen cones 20-35 mm long, red. Seed cones (4-)5-9(-10) cm long, green before maturity, ripening light brown, seed scales roughly diamond-shaped, minutely and irregularly toothed, thin and flexible to a little stiff. Seed body 2-4 mm long, the wing 5-8 mm longer.

Pacific Coast fog belt of North America within 200 km of the ocean or less, from Kodiak Island and the adjacent Alaska Peninsula, Alaska, through British Columbia, to central Mendocino Country, California. Forming pure stands or more commonly mixed with several other conifers and a few hardwoods on flats and coastward slopes, rarely forming shrubby thickets, as on rocky outcrops above the Juneau Ice Field in Alaska; 0-500(-1,200) m. The climate is very humid, annual precipitation ranges from 1300 mm to 3750 mm, the winters are moderate (in coastal Alaska snow in winter usually stays only above 200 m).

Conservation Status

Red List Category & Criteria: Least Concern

This spruce still covers vast tracts of coastal mainland and islands along the Pacific Coast of North America; it is also a pioneer after disturbance, either natural or from logging, and will return unless deliberately prevented. Consequently it is assessed as Least Concern.

Picea sitchensis occurs from tidewater up to steep mountain sides in Alaska and British Columbia, generally to ca. 900 m a.s.l. (highest record 1,189 m), always in proximity to oceanic weather. The soils are variable, usually with a thick humus layer. On Vancouver Island and on the Olympic Peninsula in Washington this spruce attains its greatest size. It is usually mixed with Tsuga heterophylla (shade tolerant competitor), Pseudotsuga menziesii and Thuja plicata, other associated conifers are Chamaecyparis lawsoniana (locally), Xanthocyparis nootkatensis, and Abies amabilis, at higher elevations replaced by Tsuga mertensiana or Abies lasiocarpa; Alnus rubra alongside rivers and Acer macrophyllum in groves are common broad-leaved trees.

Logging may have in the past depleted stands of mature trees where these have not been replaced by the same species, but in general, good regeneration has ensured that there has been limited decline in extent of occurrence and area of occupancy.

Sitka spruce grows to the largest tree of its genus and is abundant in the coastal forests between roughly 43º and 62º N along the Pacific Ocean. It is a highly valuable timber tree with growth rates exceeding those of other species and, in old growth stands, truly magnificent sizes. It is (still) heavily logged in clear cuts from natural stands including old growth (in this part of the world this means: forest that was never cut before). Smaller sizes go to the paper industry, but big trees are prized for construction and special uses such as small aircraft, masts and spars for sailing ships, oars for rowing boats, ladders, and sounding boards of musical instruments. Sitka spruce has been widely used in plantation forestry on poor acid soils in cool and wet climates such as the hills and moors of Ireland and Scotland; this timber is used for pulp wood. In horticulture it finds less use; most plantings in large parks as specimen trees date from the 19th century, and only a limited number of cultivars has been produced, mostly dwarf forms. It requires a cool and moist climate.

This species is present in several protected areas, including national parks.

References

Farjon, A. (2010). A Handbook of the World's Conifers. Koninklijke Brill, Leiden.
Eckenwalder, J.E. (2009) Conifers of the World: The Complete Reference. Timber Press, Portland.
IUCN Red List of Threatened Species, International Union for Conservation of Nature and Natural Resources. Cambridge, UK /Gland, Switzerland