Distribution of ponderosa pine is from Critchfield and Little. These slopes support nearly pure stands of ponderosa pine. They burned understory vegetation to reduce the fraction of Ponderosa Pine. Gila contains one of the world's largest and healthiest ponderosa pine forests. Vegetation varies from prairie to dense stands of ponderosa pine. Open coniferous forests of Douglas fir and ponderosa pine dominate the slopes around Lytton. They utilize pinyon, western juniper and ponderosa pine trees for cover. Disneyland's Frontierland gateway is constructed of ponderosa pine logs. Abert's squirrel also feeds on the seeds in preference to those of the ponderosa pine. The world's largest stand of ponderosa pine trees is in Arizona. Jeffrey pine is more stress tolerant than ponderosa pine in the Sierra Nevada. The shaded, north- facing walls are covered in fir and ponderosa pine trees. Elk Mountain Campground, located in a ponderosa pine forest, is about from the visitor center. Jeffrey pine wood and ponderosa pine wood are sold together as yellow pine. Typical intervals between natural fires are less than 40 years in most ponderosa pine forests.