The phenology of alpine and other mountain plants are considered particularly sensitive to changes in climate. Date of snowmelt, air and soil temperatures, and other driving factors can vary dramatically over short distances, leading to strong spatial heterogeneity in flower timing. Modeling phenology and microclimate relationships over this complex terrain requires parameterization data from numerous sites to adequately represent this topographic and environmental variation. However, the remote nature of mountain sites makes it difficult to gather frequent on-the-ground phenology observations throughout the growing season. The Mountain Watch program enlists recreational hikers and amateur botanists as citizen-scientists to supplement observations from a core network of intensively monitored phenology sites. At the core sites, trained naturalists regularly record detailed phenophase observations, and a datalogger records hourly soil (10 cm depth) and surface-air (2 cm above) temperatures. The citizen-scientist protocol is simplified, and can consist of a one-time observation from a site of their choosing, or a time-series of observations from established sites.
To date, 11,189 phenology observations from mountains throughout the northeastern United States have been submitted by participants with varied backgrounds ranging from retired botany professors, to those experiencing the woods for the first time. We will present methods for assigning data reliability metrics to observation data, and assessing the overall utility of citizen-science. We will review some of the real-world research design and implementation challenges that arose during the development of Mountain Watch, along with solutions to provide insight on maximizing citizen-science efforts. We will also discuss how these data are being incorporated, along with other model components that include a snow persistence index, cumulative degree-day formulae, plant community distribution, and topographic variables (elevation, slope, aspect, slope-shape) to understand the implications of climate change on mountain plant phenology. Finally, we highlight the opportunities to use citizen-science programs such as Mountain Watch to improve understanding of ecological concepts related to climate change, while creating a physical connection to the issue of climate change through active observation and participation.