Life Zones of the Sandia Mountains

The Sandias encompass four different named life zones due to the large elevation change, and the resulting changes in temperature and amount of precipitation, from base to top. The grassland at the western base of the mountain (the edge of the city of Albuquerque) is part of the Upper Sonoran Zone. From 5,500 feet (1,700 m) elevation to 7,200 feet (2,200 m), the Upper Sonoran Zone continues, but notable differences occur: one first finds a zone of primarily juniper, then a mixed Piñon-Juniper zone. From 7,200 to 7,800 feet (2,400 m), in the Transition Zone, Ponderosa Pine dominates. From 7,800 to 9,800 feet (3,000 m), a mixture of conifers occurs in the Canadian Zone. Finally, from 9,800 feet (3,000 m) to Sandia Crest at 10,678 feet (3,255 m), spruce and fir dominate the Hudsonian Zone.

Source: http://en.wikipedia.org/wiki/Sandia_Mountains#Ecology