Originally developed by Extension Ornamental Horticulture Specialist, Lois Stack, University of Maine Cooperative Extension with Judy Hazen Connery, Natural Resource Program Manager, Acadia National Park. Reviewed and updated by University of Maine Cooperative Extension staff, 2023. For information about UMaine Extension programs and resources, visit extension.umaine.edu. Find more of our publications and books at extension.umaine.edu/publications/.