Tony Rinaudo arrived in Africa optimistic that his tree-planting efforts would reverse the damages of deforestation and drought. His efforts failed abysmally, but one day he stumbled on a solution that had been right at his feet the whole time. His new methods have led to the regeneration of more than 200 million trees in Niger alone.

Guest:
Tony Rinaudo, author of "The Forest Underground: Hope for a Planet in Crisis" and Principal Climate Action Advisor for World Vision International