Table 1. Extent of major forest types in Colorado (from Schrupp et al. 2000). Forest Type Millions of acres Pinyon–juniper woodlands 6.1 Ponderosa pine 3.4 Mixed conifer–Douglas-fir 1.5 Aspen 3.2 Lodgepole pine 2.2 Engelmann spruce–subalpine fir 4.7