Integrated Crop Management News

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Nitrogen Loss?

December 18, 2015

Really, it just had to rain large amounts in December. Seems we can’t get any relief from worrying about excess rain and impacts on nitrogen (N). The questions have already begun – what about fall 2015 fertilizer and manure N applications?

A few things to consider.

It is quite hard to make an estimate of losses for such an extreme event and time of the year. Following are factors to consider that will affect loss potential, including if N was applied and if so what fertilizer product or manure source.

Yield Gap Analysis: What Limited Iowa Corn and Soybean Yields in 2015

December 17, 2015
Average yield gap between average potential and water-nitrogen limited yield

To evaluate how good corn and soybean yields were in 2015, farmers and agronomists compare their yields to those obtained in previous years. To answer why yields were higher or lower than past years, they develop hypotheses to explain factors that limited yields based on their own experiences, anecdotal evidence from neighbors, knowledge of crop growth and development, and weather patterns.

Wrap up and Validation of the Yield Forecast Project for 2015

December 10, 2015
Predicted vs. measured corn and soybean yields for forecast plots

During the 2015 growing season, a group of scientists from the Department of Agronomy ran a pilot project with the objective of forecasting end-of-season yields and in-season water and nitrogen dynamics (crop demand and soil supply).

Protect Your Investment by Eliminating Tillage and Keeping Residue

December 7, 2015
Field with residue removed

This fall, field observations with significant amounts of intensive tillage and residue removal provide an opportunity to rethink such practices by considering research proven practices such as no-tillage (NT) and strip-tillage (ST), which have demonstrated their effectiveness in many parts of the state and across the Midwest.