Corkbark Fir (Abies lasiocarpa arizonica): This variety of subalpine fir is distinguished by its creamy white, corky bark and it is restricted to the Rocky Mountains of southern Colorado, Arizona and New Mexico. It mixes with Abies lasiocarpa lasiocarpa in Colorado. These two firs, otherwise, are similar in many respects. Corkbark fir may be somewhat less cold hardy (U.S. Forest Service Silvics Manual)