Nitrogen is usually the nutrient most limiting crop production in Nebraska. It is subject to a variety of transformations in the soil. Some of these transformations are necessary to convert nitrogen into forms which plants can use. Other transformation or transport processes limit the availability of nitrogen to plants by converting nitrogen into forms which plants cannot use or by moving nitrogen away from the root zone.

Management factors, such as choice of nitrogen source, nitrogen placement method, irrigation management, tillage and residue management, all can affect how efficiently crops use nitrogen.