A10 - Grower-led watershed programs to evaluate nitrogen management.

Tracy M. Blackmer, Director of Research, Iowa Soybean Association; Roger Wolf, Director of Environmental Programs, Iowa Soybean Association; Alfred M. Blackmer, Professor, Agronomy, Iowa State University. Iowa Soybean Association programs in four Iowa watersheds will be summarized. Evaluations of nitrogen management practices were made in over 50% of the cornfields in each watershed. The evaluations included use of replicated trials with precision farming technologies, remote sensing, and guided sampling for testing cornstalks at the end of the season. The results showed there is substantial opportunity for improving nitrogen management practices.