September 17, 2014 — Among other benefits, trees are valuable for their ability to clean the air around us. Last week, researchers from The Nature Conservancy, Dow Chemical Company and the University of Florida published a paper in the Proceedings of the National Academy of Sciences attesting to that fact. The team found that planting trees around urban areas could contribute to the abatement of ozone and a precursor of ozone, nitrogen dioxide. Not only that, but in many cases trees could do the job at a cost equal to or lower than technological fixes.

There are cases where trees don’t necessarily pencil out — such as if land would have to be purchased for reforestation. And if planting trees comes at a cost to habitat such as important grasslands or wetlands, it may not be the right option. Still, TNC’s chief scientist Peter Kareiva writes in a blog post about the study, “Kroeger and colleagues show that forests can be added to the engineering solutions in a significant way. … And unlike the engineering solutions, forests bring numerous extra benefits as a bonus — they sequester carbon and help to mitigate climate change, they can cool air temperatures, they can help improve water quality and reduce flood risk, and they are habitats for wildlife and sites for recreation.” Photo by USFS Region 5 (Creative Commons | Flickr)