This document discusses the benefits of replanting half of the land currently used for lawns with trees. It notes that replanting 20 million acres would create an area larger than several famous national parks combined. The document outlines many sustainability benefits of trees, including improved air quality, stormwater management, carbon storage, and habitat provision. It also lists benefits for human health and well-being such as stress reduction, lower energy costs, and higher property values. Maintaining biodiverse landscapes supports pollinator populations like chickadees that require caterpillars found on many different tree species.