What could possibly be bad about planting trees? In her talk about trees in urban landscapes, Sonja Duempelmann considers social, cultural, and environmental factors to answer this question: we need more trees in our cities, but tree-planting initiatives must be careful as to how, where, and when they plant. Sonja Dümpelmann is an award-winning landscape historian and Associate Professor at the University of Pennsylvania’s Weitzman School of Design. Trees in cities and our relationship to them are the focus of her most recent book SeeingTrees: A History of Street Trees in New York City and Berlin (Yale Univ. Press, 2019). She is interested in studying relationships between subjects such as architecture and landscape; those in power and those subjected to that power; and social and political processes, scientific and technological accomplishments, and landscape transformation. This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at https://www.ted.com/tedx