The official state tree of Colorado is the Colorado Blue Spruce, scientifically known as Picea pungens. This evergreen conifer is recognized for its distinctive color and stately pyramidal form. Its designation reflects the tree’s native presence within the Rocky Mountains and its connection to Colorado’s landscapes.
The Official Designation
The Colorado General Assembly formally designated the Blue Spruce as the official state tree on March 7, 1939, approving House Joint Resolution No. 7. This resolution followed decades after a popular movement first championed the tree. The legislative process followed a non-binding vote taken by the state’s schoolchildren on Arbor Day in 1892, who expressed a clear preference for the Blue Spruce. The official designation was adopted by Concurrent Resolution and is therefore not recorded as statutory law under a specific Colorado Revised Statute section.
Identifying the Colorado Blue Spruce
The Colorado Blue Spruce is a medium to large tree, typically growing between 30 and 60 feet tall in cultivation, though specimens in the wild can exceed 100 feet. Its most distinguishing feature is the color of its needles, which range from dull green to a striking silvery-blue hue. This blue color results from a thick, waxy coating, called glaucous bloom, that helps the tree manage water loss in its dry, high-elevation habitat.
The needles are stiff, sharply pointed, and four-angled in cross-section, giving rise to the species name pungens, meaning “sharply pointed.” These needles are arranged singly on the branches and are about one to one-and-a-quarter inches long. Mature trees develop dark gray bark that is often deeply furrowed with scaly plates. The cones are cylindrical, light brown, and measure between two and four inches long, featuring thin, flexible scales.
Native Range and Ecological Role
The Colorado Blue Spruce is native to the central and southern Rocky Mountains, typically found in the montane zone between 6,000 and 11,000 feet. This species prefers moist soil conditions, often thriving along stream banks, in canyon bottoms, and on the edges of wet meadows.
In its natural habitat, the blue spruce is rarely the dominant species, often growing in scattered groves alongside other conifers like Douglas-fir, ponderosa pine, and Engelmann spruce. The tree’s dense, pyramidal growth habit makes it an effective windbreak, providing shelter for wildlife and protecting stream banks from erosion. Though it is not a major source of timber due to its brittle wood, its hardiness and symmetrical shape have made it one of the world’s most popular ornamental and landscape trees.