Ellen Wohl received a BS in geology from Arizona State University and a PhD in geosciences from the University of Arizona before joining the faculty at Colorado State University. Her research focuses on river form and process and she has conducted field research on every continent but Antarctica. Much of her recent emphasis has been on interactions between rivers and downed trees, which gave rise to this book. She has written several technical books and books for non-specialist readers. She enjoys reading, hiking, and traveling.