Douglas-fir (Pseudotsuga menziesii) trees are common in the mountains of western North America, including here in Arizona. Douglas-firs have single, flat, blunt-tipped, blue-green needles that grow in all directions around the branch because of their alternate spiral leaf arrangement.
Despite their common name, Douglas-fir trees (Pseudotsuga species) are not actually Fir trees (Abies species), although both Douglas-firs and Firs are in the Pine Family (Pinaceae).
The easiest way to identify Douglas-firs are by their unique cones. The papery, red-brown cones of Douglas-firs have distinctive three-pointed bracts emerging from the cone scales.
Douglas-firs grow at elevations from 5200 to 10,000 feet (1585 to 3048 m), and they can be up to 200 feet (61 m) tall when mature. Birds, squirrels, and mice feed on the seeds, and other animals browse on the twigs and needles.