Colorado spruce tree plants are evergreen trees and grouped with the conifers. They are members of the pine family. The species plant is native to the Rocky Mountain states in the United States. One of the cultivars to grow is 'Glauca,' which is a Latin word that indicates a grayish-blue color. It is the official tree of the state of Colorado. The Colorado Blue Spruce's silvery-blue needles are prickly to the touch and have a strong, fresh, piney smell. Its pyramidal shape, foliage color, and wonderful smell make this plant a classic choice for a Christmas tree.