PINACEAE 



Blue Spruce. Colorado Blue Spruce 

 Picea pungens Engelm. {Picea parryana Parry) 



HABIT. A tree 80-100 feet high and 1-2 feet in diameter 

 (max. 150 by 4 feet); bole symmetrical, tapering, knotty; crown 

 typically dense and conical when young, becoming thin, ragged 

 and pyramidal in age, and extending to the ground on open 

 grown species. The State Tree of Colorado. 



LEAVES. Extending at nearly right angles from all sides 

 of twig; 1-1 J4 inches long; 4-angled; blue-green, frequently 

 with a silvery, glaucous bloom which persists for 3-4 years on 

 young trees; rigid, tipped with long, bristle-sharp point; 1 resin 

 duct in an angle of leaf in cross section. 



FLOWERS. Male yellow, tinged with red; female pale green. 



FRUIT. 2]/4-4y2 (mostly SYz) inches long, oblong-cylin- 

 drical; sessile or short-stalked; cone scales tough, stiff, spread- 

 ing, with erose margins; shiny, light chestnut-brown; not fall- 

 ing until fall of second season. Seed : Yq inch long, dark chest- 

 nut-brown; broad oblique wing about Y2 inch long. 



TWIGS. Glabrous; stout and rigid; orange-brown to gray- 

 brown. Winter buds: l^-Yi inch long; broadly ovoid and ob- 

 tuse; light chocolate-brown; bud scales usually reflexed. 



BARK. Pale to dark gray; thin and scaly on young trucks, 

 becoming "^A-lYi inches thick and deeply furrowed with rounded 

 ridges on old trunks. 



WOOD. Rather similar to white spruce but brittle, knotty 

 and of little value. The chief use of this tree is for ornamental 

 planting. 



SILVICAL CHARACTERS. Moderately tolerant, but least 

 so of spruces; slow-growing; long-lived; reproduction generally 

 scanty because of dense ground cover; widespread, moderately 

 deep root system and decidedly windfirm. 



HABITAT. Transition and Canadian zones, but mostly below 

 the Engelmann spruce belt; varying from 6,000-9,000 feet in 

 the north to 8,000-11,000 feet in the south; rich, moist soils, 

 typically on stream banks; never abundant; in scattered pure 

 groves or singly in mixture with ponderosa pine, Douglas-fir, 

 alpine fir, Engelmann spruce, and hardwoods. 



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