NYC Tree Guard (IMAGE) Columbia University Caption In a new study, Columbia researchers find that street trees with protective guards soaked up runoff water six times faster than trees without guards. Credit Lizzie Adkins, Columbia University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.