spruce, any plant of the genus Picea, evergreen trees or shrubs of the family Pinaceae (pine family) widely distributed in the Northern Hemisphere. The needles are angular in cross section, rather than flattened as in the related hemlocks and firs. The Norway spruce (P. abies), an important timber tree of Europe, is one of the most commonly cultivated evergreens. The Siberian spruce (P. obovata) grows in coniferous forests (taiga) of Russia and Siberia, the Oriental spruce (P. orientalis) is a major species of S Europe, and the yeddo spruce (P. jezoensis) of Manchuria and Japan is sometimes dwarfed and potted (see dwarf tree). North American spruces used for timber are the red spruce (P. rubens), white spruce (P. glauca), and black spruce (P. mariana) of the East; the Engelmann spruce (P. engelmanii) of the Rocky Mountain forests; and the Sitka spruce (P. sitchensis) of the Pacific forest belt. Numerous spruces are cultivated as ornamentals; the most popular North American garden spruce is the frosty- or silvery-blue-needled Colorado blue spruce (P. pungens). Commercially, spruces are of particular value as a major source of pulpwood for the manufacture of paper. Wood of the various species is usually light, soft, and straight-grained and has been used for interior and exterior construction work, boats, airplanes, and woodenware. The bark is sometimes used for tanning, and some species yield a gum resin. Spruce beer has been made from the young shoots of the red spruce and the black spruce. Native Americans in the West have used spruce gum for caulking, the inner bark for food, and strips of spruce for weaving watertight mats and baskets. Spruce is classified in the division Pinophyta, class Pinopsida, order Coniferales, family Pinaceae.

red spruce: see spruce.

Douglas spruce: see pine.

Any of about 40 species of evergreen ornamental and timber trees that make up the genus Picea (pine family), native to temperate and cold regions of the Northern Hemisphere. These pyramid-shaped trees have whorled branches and thin, scaly bark. The needlelike, spirally arranged leaves connect to their stems via a peglike woody base, which remains on the twig when the leaf falls. Tough, finely grained, resonant, and pliable, spruce wood is used for sounding boards in pianos and bodies of violins, as well as in construction, for boats and barrels, and as pulpwood. Common species throughout most of northern North America are black spruce (P. mariana), a source of spruce gum, and white spruce (P. glauca), a source of good timber. Blue, or Colorado spruce (P. pungens) is used as an ornamental because of its bluish leaves and symmetrical growth habit.

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