Without fungicides, apply 90 lbs/ac N. It is not recommended to grow wheat without applying fungicides, as you will not achieve the highest yield potential that could be available with fungicides.
With fungicides, use 120 to 150 lbs/ac N depending on past field history, organic inputs, soil organic matter and nitrate levels, and economics. Beware of lodging when going with high rates. Try strip trials of different rates in the field to experiment and learn how to keep rates high, while avoiding lodging.
To maximize yield, nitrogen must be applied uniformly across the field. Uniform application is more critical than the form of nitrogen fertilizer applied.
Urea-Ammonium Nitrate Solution (UAN) (28-0-0 or 32-0-0) applied with streamer nozzles gives excellent, uniform nitrogen application and has shown small yield advantages (2.5 bu/acre). UAN applied through streamer nozzles causes little or no leaf burn.
Applying 28% nitrogen (UAN) as an overall broadcast treatment (using flood jet or tee-jet nozzles) to emerged cereal crops is NOT RECOMMENDED. The addition of 28% to an herbicide application, especially contact herbicides, will greatly increase leaf injury and yield loss.
If applying dry fertilizer, airflow technology can be utilized to improve spreading uniformity, although uniformity is not guaranteed.
Spinner spreaders often have the greatest inconsistency in spread pattern. If spinners are employed, consider double spreading the field (i.e., 6-m or 20-ft centres at half the rate, instead of 12-m or 40-ft centres) to overcome this. Newer technology in spinner spreaders, especially with custom application, can improve the spread pattern and cut down on overlaps or streaking within the field. Be sure to ask your Sylvite Sales Rep or Ag Consultant to decide on the best option to fit your operation.