It is critical to monitor the phenology—the timing of seasonal biological events, such as flowering and migrations—of plants and animals because of its ecological importance, response and sensitivity to climate change, and utility as an educational tool. This project will serve as a pilot to show how a park may incorporate phenology monitoring into its inventory and monitoring activities, helping to meet monitoring, research, management, and education needs. The project will feature collaboration between the USA National Phenology Network (NPN), The Wildlife Society (TWS), NPS Northeast Temperate Inventory and Monitoring Network (NETN), Acadia National Park, and Appalachian Mountain Club (AMC). We will use this pilot to develop a plan for ongoing phenological monitoring along the Appalachian National Scenic Trail, which has identified phenology as a high priority vital sign, and as a model for other parks across the United States.