A farm just outside the north-central Iowa town is home to Iowa State University’s Agriculture Drainage Research and Demonstration Site, a facility that has been working to further Iowa State University’s water conservation efforts since 1990.
By John Sawyer, Department of Agronomy
This year's dry growing season has raised several soil fertility questions. In some cases, there have been relatively normal crop production and no need for management changes. In other situations with severely damaged crops, there is potential for adjustments for the 2013 corn crop.
When a corn plant is stunted, or not growing normally, nitrates can build up in the plant. Typically nitrogen that is taken up by the corn plant is converted to amino acids — the building blocks of protein — but in the stressed plant this conversion does not occur. And that's why producers need to know how to handle and feed drought-damaged corn in silage form, according to Steve Ensley of Iowa State University's Veterinary Diagnostic and Production Animal Medicine (VDPAM) department.
Stalk nitrate test is best suited for understanding when N applications over time are greater than crop need, and an economic and environmental benefit can come from improved application rate.
Continued wet soil conditions into June with warm soils, prolonged saturation and tile drainage enhance nitrate loss. One way to determine nitrogen (N) loss is to calculate an estimate.
