Crop Yields of Long-Term Rotations and Nitrogen Fertilization of Corn in Northern Iowa
Crop yield can be significantly affected by the crops in a rotation because crop characteristics and associated management practices may influence many soil properties and incidence of weeds and pests. Including legumes in a rotation usually increases soil nitrogen (N) supply for corn. A crop rotation study was started at this farm in 1954 to study the effect on crop yields of seven crop sequences and N fertilization rates for corn. Several rotation and N fertilization changes were made over time until 1984. This report summarizes results since 1985.