At 1.6 million acres the Kaibab National Forest borders both the north & south rims of the Grand Canyon, in northern Arizona. Vegetation varies by elevation & exposure. Tree species are ponderosa pine, Douglas-fir, aspen, blue spruce, oak, pinyon pine, & juniper. They enhance the beauty of the landscape, hold soil in place, & provide cover & food for wildlife. As elevation decreases, trees give way to bitter brush, oak, sagebrush, & cliffrose. There are areas entirely free of tree growth.