The USLE_1981-4 project data (Universal Soil Loss Equation) was collected from of (9) sites at (4) locations. A Swanson rotating boom simulator with (30) V-Jet 80100 nozzles applied rainfall at two different intensities, 60 or 130 mm/hour depending on how many nozzles were turned on. Specially designed flumes used with the FW-1 automatic water level recorder were used to obtain continuous runoff flow measurements. The sites in this data set followed a standardized rainfall simulator protocol which future studies by multiple investigators would continue to use. The data set contains rainfall simulator hydrologic and erosion data as well as vegetation and ground data collected in spring and fall from 1981 to 1984. All sites had (3) treatments with (2) replications. The vegetative plot manipulation treatments were: clipped, all vegetation clipped at ground surface and removed, bare, vegetation clipped and removed with all rocks larger than 5 mm removed, natural, vegetation left natural, tilled, all vegetation removed and soil tilled. Dataset data was published in Proceedings of the Rainfall Simulator Workshop 1985 Tucson, AZ in table format appendices. There is also (8) supporting data files with related site data. The raw data for the New Mexico site is not currently available.