Hal Rosner is a certified arborist in Philadelphia active on civic projects to help grow the city's tree canopy. He discusses the Philadelphia Tree Plan, the debacle of the FDR Park development, strategies for homeowners interested in trees for their neighborhood, the politics of including trees in development, and much more. He is a co-host of the award winning "Plant a Trillion Tree" podcast that features more than 200 episodes and an international audience.