The dataset depicts land use/cover in the Cayuga Lake Watershed. This geographic dataset was constructed using a multi-resource approach. To map small scale land uses, high resolution aerial imagery available from the New York State Digital OrthoimageryProgram (NYSDOP) was interpreted by a trained GIS analyst according to a multi-tiered classification scheme similar to that used by Tompkins County, New York to map land use in 1995. To map large scale land uses and land cover types, two sets of Landsat Thematic Mapper images were analyzed. One set was analyzed by the USDA National Agricultural Statistics Service Research and Development Division, and published as the Cropland Data Layer for the state of New York. To distinguish between different forest cover types, Landsat-5 TM images were radiometrically and geographically corrected, and analyzed using a supervised classification procedure. These separate layers were overlayed to produce the final vector layer. This geographic dataset was developed by the Cayuga Lake Watershed Network as part of a larger project, in conjunction with Dr. Douglas Haith and Cornell University, to model nutrient loading in the Cayuga Lake watershed. The model used is the Generalized Watershed Loading Function (Haith and Shoemaker, 1987). Haith, D.A. and L.L. Shoemaker, 1987. Generalized Watershed Loading Functions for Stream Flow Nutrients. Water Resources Bulletin, 23(3), pp. 471-478.