ISSUE 9 July 8, 2010
WHEN POST-N WHEAT PROTEIN ENHANCEMENT OPPORTUNITY ENDS AND FRAUD BEGINS
The time window for post-N wheat protein enhancement is immediately after flowering until the wheat berries begin to turn milky. Any application of N after this time does not contribute to wheat protein enhancement. However, application of N from milk stage to harvest may constitute fraud on behalf of the grower. Ammonia that clings to the wheat kernel may show up as a false positive for protein in elevator tests and result in the illusion of a higher protein wheat than was harvested. The potential for fraud is greatest the closer the application of N is to harvest, but N can cling to the surface of a wheat kernel for some time. Do not apply any N fertilizer to wheat once the kernels begin to turn milky, except for the ammonium sulfate required to enable a pre-harvest glyphosate application.
NDSU Extension Soil Specialist