The March 21 observance highlights the important role that trees and their forest ecosystems play in creating a healthy environment. Here at the Jedediah Smith Redwoods State Park in California, giant coastal redwoods—plus a variety of other trees, shrubs, bushes, flowers, ferns, mosses, and lichens—provide a haven for many creatures, even the small and slimy. This is banana slug territory, and visitors are likely to encounter the bright yellow banana slug—the largest slug in North America—as they journey through the park.