Children walk down a tree-lined promenade in Philadelphia.
The Mayor's Fund for Phialdelphia

Trees as infrastructure

From environment to edifice.

How likely? How soon? What impact?

Human beings have ancient connections to trees. But over the last 200 years we have decimated the planet's forests. Nowhere is this more clear than in cities. Despite the well-understood benefits trees provide—reducing heat loads on streets and buildings, and absorbing stormwater runoff, among others—we have not preserved or expanded urban forests adequately. What's more, this neglect is highly racialized in societies with a history of discrimination.

Over the next decade, however, a new web of technologies will refocus our attention on the value of trees as infrastructure, and will help us care for and expand the urban canopy. We'll build more sophisticated models by mashing up data on tree canopies sensed from satellites and drones, surveys of trunk characteristics taken from streets, and continuous digital monitoring by sensors mounted on trees directly. Coupled with tools that engage city dwellers as empowered and informed stakeholders in urban forestry, these techniques point towards a future where trees are fully formalized and valued on the same level as built infrastructure. This will be a crucial step in systematically integrating urban forestry into city planning and development.


Signals are evidence of possible futures found in the world today—technologies, products, services, and behaviors that we expect are already here but could become more widespread tomorrow.