White Fir are one of the large conifers that inhabit elevations from around 7000 to 10,000 feet. The often share an area with Aspen and/or Ponderosa Pine. The have soft blue-green needles that are plump and succulent. The sap has a pleasant citrus odor. On a personal note, it's my favorite tree in the area. As elevation increases we see the very similar A. lasiocarpa. A. concolor is more common in the eastern part of La Plata county, with large stands surrounding both Lemon and Vallecito reservoirs.