(P. Engeinuinni), native to the Rocky Mountain region and extending westward to British Columbia and California, is a handsome tree of high altitudes. It grows from 20 to 150 ft. high, with slender branches and oval cones, sometimes 3 in. long. The blue spruce (P. pungens), native to the central Rocky Mountain region, is one of the most distinctive American species. It grows from 8o to 15o ft. high, with stiff, horizontal branches, and rigid, bluish-green to silver-white, spiny tipped leaves, and oblong cones, 21 to 4 in. long. Several varieties with characteristically blue foliage, as the well-known Koster blue spruce (var. Kosteriana) are widely grown for ornament.
(P. sitchensis) occurs along the Pacific, extending about 5o m. inland, from Kodiak island, Alaska, southward to northern California. It is the most massive of the spruces, sometimes attaining a height of 190 ft. and a basal trunk diameter of 20 ft., but it usually grows about ioo ft. high, with a trunk 3 ft. in diameter, with widely spreading, rigid branches, stiff, usually prickly-pointed leaves, and oblong cones 2 to 4 in.
in length. The Sitka is a valuable timber tree, and is extensively lumbered. The rare weeping spruce (P. Breweriana), with hanging branches clothing the trunk to the ground and with the few hori zontal branches decorated with cordlike hanging branchlets, is confined to the coastal mountains of northern California and adjacent Oregon.
Among the various Old World spruces planted as ornamental trees are the Serbian spruce (P. Omarika) ; the oriental spruce (P. orientalis), of Asia Minor; the Himalayan spruce (P. Smithiana), the Alcock spruce (P. bicolor) and the tiger-tail spruce (P. polita), natives of Japan.
See Veitch, Manual of Coniferae (2nd
C. S. Sargent, Manual of the Trees of North America (2nd 1922) ; L. H. Bailey,
Standard Cyclopedia of American Horticulture (1914-27) and Manual of Cultivated Plants (1924), and G. B. Sudworth, "Check List of the Forest Trees of the United States, Their Names and Ranges," U.S. Dept. Agric., Misc. Cir. 92 (1927).