Mesic Resource Persistence reflects how reliably a location supported productive herbaceous vegetation — grasses, forbs, and wet meadow plants — during the late growing season (July 15 through September 30) from 1984 to 2025. Each year, a pixel is classified as productive if its greenness index (NDVI) meets or exceeds a standard threshold for mesic vegetation (0.3). Persistence is the percentage of those years a pixel was productive — a proxy for long-term water availability.

Min Years Productive sets the minimum persistence threshold for visible pixels. The lowest meaningful value is 2% (approximately one productive year). For example, setting this to 25% shows only locations that were productive in at least 1 out of 4 years, filtering out rarely-wet areas.