1. An Overview of On-Farm Nitrogen Rate Research

Because crop advisors, farmers, and some in the fertilizer industry questioned the University's N recommendations as being too low and raised concerns that the N calibration research had been done primarily in small plots on University Experiment Station land. numerous N calibration studies for corn after soybeans were conducted on farmers' fields in southern Minnesota and northeastern Iowa from 1989 through 2002 to validate present N recommendations. On-farm replicated trials were conducted by University...