Tropical Forest's Vanguard Pushes North (IMAGE) University of Maryland Caption A newly established black mangrove grows amid salt marsh plants north of St. Augustine, Florida, near the northern limit of this cold-sensitive tropical tree's range. Mangroves are expanding into North Florida as killing frosts become rare there. Credit Courtesy of Kyle C. Cavanaugh 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.