In Nanjing, China, a project is underway to introduce two high rise towers, covered with native trees and plants. The purpose is to be giant air filters and the towers are planned to soak up 25 tons of carbon dioxide annual. Plus they are beautiful when compared to regular high rises. More projects are planned in other cities, as China’s air pollution is becoming a health crisis. The trees also block sound and keep the building cool. These building give city dwellers an opportunity to enjoy nature too!