Conifer Trees Database

Description. Colorado spruce is an evergreen coniferous species of tree that grows to mature heights of 165 feet (50 m) tall with a trunk 5 feet (150 cm) in diameter, measured at breast height.

• Crown is broadly conic in shape.
• Bark is gray-brown in color.
• Branches grow slightly to strongly drooping; non-pendant twigs are stout and yellow-brown in color, usually glabrous.
• Foliar buds are dark orange-brown in color, measuring 0.24 to 0.48 inch (6 - 12 mm) in size, with a rounded to acute apex.
• Leaves are needle-like, measuring 0.6 to 1.2 inches (1.6 - 3 cm) long, 4-angled in cross section, rigid, Blue-green in color, bearing stomata on all surfaces, with a spine-tipped apex.
• Pollen cones are red in color, growing in whorls of 3 to 5 at the proximal end of new shoots, primarily borne in upper crown.
• Seed cones are also borne in the tree's upper crown. They are pale green or red when fresh, ripening to pale buff brown, 2 to 5 inches (5 -12 cm) long with elliptic to diamond-shaped scales, widest below middle. Seed cones mature in August; seed shed is from September into winter.

Distribution. This species is native to USA - Idaho, Wyoming, Utah, Colorado, New Mexico and Arizona, growing in the montane zone at elevations varying from 5,800 to 8,800 feet (1,830 - 2,740 m) above sea level in the northern range of the species, and from 6,800 to 9,800 feet (2,130 - 3,050 m) in southern areas. It prefers conditions where the climate is cool and summer-wet, with mean winter minimum temperatures of 12 to 48°F (-11.1 - 8.9°C) and mean summer maximum temperatures of 70 to 72° F (21.1 - 22.2°C). Average annual precipitation varies from 18 to 24 inches (460 - 610 mm), with half of the annual precipitation falling during the growing season. It is the most drought-tolerant species of Picea in North America.

Hardy to USDA Zone 3 (cold hardiness limit between -40 and -30° (-39.9° and -34.4°C).