California Agricultural Land Use Estimates Derived from Pesticide Use Reporting Data

Agricultural land use estimates are vital to understanding agricultural production, economic contributions, and water demands. A method to estimate spatially and temporally distributed agricultural land use was developed for California. Pesticide application records were processed to develop annual statewide estimates of agricultural land use at approximately 1-square mile resolution. Evaluation of method performance included statewide analysis and enhanced analysis of an agriculturally diverse 5-county subarea. Results were compared to two independent reference datasets: (1) maps of remotely sensed agricultural land use and (2) agricultural economic reports. Results show reasonable correspondence with the reference data sets as evaluated by linear regression, percent average estimation error (PAEE), and spatial analysis (r2 = [0.28 - 0.80], PAEE = [1.7% - 22.7%]). This novel method provides independent evaluation and validation of, and reduces uncertainty in, estimates of current and historical land use.