Yishan Wong applies Silicon Valley know-how to restore actual valleys, forests, and other green areas. : Former Reddit CEO Yishan Wong left Silicon Valley and moved to Hawaii in 2019 to focus on reforesting projects. In 2017, fresh into the first year of the presidency of Donald Trump, who openly stated he didn’t believe in climate change, Silicon Valley veteran Yishan Wong looked at the future with concern. What would happen if the world failed to reduce greenhouse gas emissions, he wondered. And was it possible to find a reasonably priced, deployable solution to at least absorb emissions?