Trees Share Their Water to Keep Nearby Stumps Alive

Scientists tracked water and sap flow in a kauri tree stump in New Zealand.

Scientists tracked water and sap flow in a kauri tree stump in New Zealand. SEBASTIAN LEUZINGER

Scientists have discovered that trees share water through interconnected root systems with nearby stumps, keeping the almost-dead stumps alive. The findings, published in the journal iScience, are the latest addition to a growing body of research showing how trees and other organisms work collaboratively to maintain a healthy forest.

Researchers at the Auckland University of Technology launched their study after finding a living kauri tree stump, as evidenced by freshly produced resin, while on a hike in the Waitakere Ranges on New Zealand’s North Island, Science magazine reported. They quickly set up monitoring equipment to track sap and water flow in the stump and its neighboring trees. They found that the stump was taking in water, while the trees around it were releasing it through their root systems.

Exactly why neighboring trees keep stumps alive remains a mystery. The stump could possibly provide additional stability for the host tree, acting almost like an additional anchor in the soil, the scientists said. It could also be because maintaining the connection gives a host tree access to additional resources through the stump’s extended root system.

For more on how trees “talk” to each other and why, click here.