California's Street Trees Are Worth About $1 Billion

It’s hard to motivate meaningful responses to abstract environmental problems. That’s why some scientists have thrown their weight behind putting dollar signs on nature. Their hope is that if people better grasp the dividends society reaps from rivers, forests, soil, and the atmosphere, they might support investing in protecting it.

Certainly, that’s the philosophy the U.S. Forest Service has adopted in the agency’s work with urban canopies. Scientists there have calculated the dollar value of urban trees in cities around the U.S., measuring and monetizing the benefits trees provide by sequestering carbon, improving air quality, providing shade, reducing noise, and absorbing rainfall. They’ve built specialized software, i-Tree, to inventory urban trees and help evaluate their worth.