When should a second application of nitrogen be made to wheat to be harvested as grain?
Only a small portion of the total nitrogen used by the crop is required prior to jointing (usually around 20 to 30%). Topdress nitrogen is best utilized if applied prior to jointing. Evaluate fields as growth begins in the spring. If tiller numbers are low, producers will want to apply the fertilizer early. The amount to apply should be based upon amount of nitrogen present in the field and yield potential. Ungrazed wheat will use about 1.7 pounds of nitrogen per bushel of yield. Base rates on projected yield considering: 1) the crop condition, 2) availability of moisture, 3) residual nitrogen at planting (from soil test), and 4) amount of fertilizer applied preplant. Source of nitrogen has little to do with yield response. Apply the source that can be most efficiently and economically applied. To reduce leaf burn with high rates of liquid applicator, consider using dribble nozzles. By late February, the wheat will reach a stage of growth where nutrient and water uptake is increasing.
