10/19/2026
More than 50 years ago, researchers at the Hubbard Brook Experimental Forest conducted a bold experiment. They clear-cut an entire forested watershed and prevented regrowth for two years to see what would happen. The results surprised even many scientists. Streamflow increased, stream temperatures rose, and large amounts of nutrients stored in the ecosystem washed away. Nitrate levels in the stream increased more than 40-fold, and losses of calcium, potassium, and other important nutrients skyrocketed.
The big takeaway was that trees do much more than provide shade and beauty. They act like nature's nutrient recycling system, capturing and reusing valuable elements that might otherwise be lost from the landscape. When the trees were removed, that system broke down and nutrients flowed downstream instead of staying in the ecosystem.
Why does this matter in Tennessee?
When we talk about urban forests in Nashville, Memphis, Chattanooga, Murfreesboro, and communities across our state, we're not just talking about aesthetics. Trees help slow stormwater, filter pollutants, protect streams, reduce summer heat, and keep nutrients where they belong. Every mature tree we preserve and every new tree we plant helps strengthen these natural services that support healthier neighborhoods and cleaner water.
As our communities continue to grow, the Hubbard Brook study reminds us that trees are not simply landscape features. They are part of the infrastructure that keeps our environment functioning well.
Sometimes the value of a tree becomes most obvious when it's gone.
Learn more about Tennessee's urban forest and the importance of proper tree care at https://tufc.com/. And become a member today at https://tufc.com/membership/ to support our mission to promote healthy and resilient urban forests!
