Flagstaff, AZ – It used to be that camping was the ultimate "green" activity. But many now enjoy the great outdoors in the comfort of giant motor homes, which suck-up a lot of energy. For this Earth Day, we visit a Flagstaff campground that's working hard to reduce its carbon footprint. In the process, it's becoming a national model for "green" RV camping. Arizona Public Radio's Gillian Ferris Kohl reports.