On a recent afternoon, University of Florida watershed ecologist David Kaplan and Ph.D. candidate Katie Glodzik hiked through the Withlacoochee Gulf Preserve, on the Big Bend coast of northwestern Florida. Not long ago, red cedar, live oaks, and cabbage palms grew in profusion on the raised “hammock island” forests set amid the preserve’s wetlands. But as the researchers walked through thigh-high marsh grass, the barren trunks of dead cedars were silhouetted against passing clouds. Dead snag cabbage palms stood like toothpicks snapped at the top. Other trees and shrubs, such as wax myrtle, had long been replaced by more salt-tolerant black needlerush marsh grass.