China's monumental effort to plant nearly 200 billion trees since the 1970s is now facing a critical test. Scientists have discovered that these vast new forests, a cornerstone of the fight against climate change, are severely impacting water resources. This urgent challenge has spurred the country to lead a global shift toward "water-smart forestry," adapting its strategy for a world where every drop counts. On the show: Steve, Fei Fei & Yushan