Split Nitrogen Application Trial

Farmers understand it is best to apply nitrogen to the crop at or right before rapid growth occurs. However, 100 percent in-season nitrogen applications are faulted because of potential for unfavorable weather conditions delaying applications and subsequent deficiency occurring. This trial looks at how split nitrogen applications can be used to address environmental risks of pre-plant nitrogen application as well as unfavorable application conditions in-season.

Yield Response of Planting Corn in Early April

Corn is planted earlier each year, which is one important component in maximizing grain yield. Earlier planting dates can be attributed to larger farms, less spring tillage, improvements in corn hybrids, improved drainage systems, and better seed treatments. Research conducted at the ISU Northwest Research Farm from 2006 through 2009 showed that the planting window for 98 percent or greater yield potential in northwest Iowa is April 15 to May 9. A 95 percent or greater yield potential can be realized from April 15 to May 18. A study was conducted from 2009 through 2011 at the Northwest Research Farm to determine how corn planted in early April compares with corn planted in the recommended planting window for the area.