Since 1979, Jadav Payeng has been planting hundreds of trees on an Indian island threatened by erosion. In this film, photographer Jitu Kalita traverses Payeng’s home—the largest river island in the world—and reveals the touching story of how this modern-day Johnny Appleseed turned an eroding desert into a wondrous oasis. Funded in part by Kickstarter, "Forest Man" was directed by William Douglas McMaster and won Best Documentary for the American Pavilion Emerging Filmmaker Showcase at the Cannes Film Festival in 2014.See more photos of the world's largest river island.The Short Film Showcase spotlights exceptional short videos created by filmmakers from around the web and selected by National Geographic editors. We look for work that affirms National Geographic's mission of inspiring people to care about the planet. The filmmakers created the content presented, and the opinions expressed are their own, not those of the National Geographic Society. To submit films for consideration, please email SFS@ngs.org.