The main vegetation zone in the lower elevations of the Rocky Mountains is the forest.

A wide variety of tree species, including conifers like ponderosa pine, Douglas fir, and spruce, are found in this zone. Numerous bird species, bears, deer, and other wildlife depend on these woodlands for their essential habitat. These lower-elevation forests' abundant biodiversity supports a variety of habitats, enhancing the area's ecological well-being. These forests are vital to environmental sustainability and a major attraction for outdoor leisure and tourism because they also serve a critical role in soil conservation, water control, and carbon storage.