Tree Targets (IMAGE) University of Iowa Caption An University of Iowa study has identified "hotspots" in the Twin Cities, Minnesota, where carbon emissions far outpace trees' ability to store the pollution. The analysis may help city planners determine the best locations to focus tree-planting efforts. Credit Heather Sander lab, University of Iowa 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.