Effect of Nitrogen Rate and Row Spacing on Sweet Corn Yield and Residual Soil Nitrogen (1996)


Vegetable growers in the Willamette Valley use high rates of nitrogen fertilizers, often exceeding 250 to 300 pounds actual N/acre per season. While growers believe that these rates are necessary to achieve maximum yields and quality, a considerable portion of the applied fertilizer is not taken up by the crop. This has raised concerns that the remaining N may be contributing to nitrate pollution of groundwater. Improved efficiency of nitrogen management may be possible if the fertilizer could be placed for maximum contact with the root system.