Ponderosa pine (Pinus ponderosa) is one of the most common trees in Rocky Mountain National Park. They are trees of montane forests and very well adapted to the long winters, winds, cold temperatures, and dry conditions found in large areas of the Rocky Mountains. Ponderosas are evergreens, meaning they do not drop all their needles in autumn. They do, however, lose some of their needles in the autumn, especially in drought years, and the accumulation of needles beneath trees is useful as it serves as a natural mulch to help keep in soil moisture. Ponderosas can be recognized by having needles in bundles of three and the reddish yellow bark that smells somewhat like vanilla on mature trees.
Ponderosas are used by many types of wildlife for food and for shelter. The two native tree squirrels that live in Rocky Mountain National Park, the Abert's squirrel (Sciurus aberti ) and the chickaree (Tamiasciurus hudsonicus ), use the pine's seeds as food. Squirrels are often seen holding pinecones like ears of corn and gnawing off the tough outer scales of the pinecone to get to the seeds. Yellow-bellied and Williamson's sapsuckers (Sphyrapicus varius and Sphrapicus thyroideus) drill horizontal holes in ponderosas to get at the sap, which they eat. They also visit old drillings to eat the insects attracted to the oozing sap. Clark's nutcracker, pine siskins, sparrows, chickadees, owls, and many other birds use ponderosa pine forests for food and shelter. Moths are reported to be more numerous in ponderosa forests in some locations. Elk and mule deer, as well as a wide variety of other wildlife, use these forests for cover.
Humans have used ponderosas, not only for timber to build structures and for firewood, but also as food and medicine. Native Americans used the inner bark as food in times of starvation, and as an early form of (very fibrous!) chewing gum. They also were reported to have used the resin as an eye wash, as a salve for skin problems, and to sooth joint aches and scaly skin.