Dense spatial and temporal data on yield and soil fertility have been analyzed to suggest a newly possible approach to soil fertilizer recommendations. Crop removal from a 10-year history of yield maps was calculated on a 5 x 5 m (approximately 16 x 16 ft.) grid. Soil test change was estimated with a regression procedure on the same grid spacing. The ratio of phosphorus (P) and potassium (K) removal to soil test change was calculated. Resulting maps show spatial relationships to past management and landform processes.