Once wheat starts to green up it is time for you to apply nitrogen.
For years Ontario research indicated that maximum yield came from about 90-100 pounds per acre of actual nitrogen. Work by Dr David Hooker University of Guelph the past two years and farm plots by the Ontario Soil and Crop Improvement Association under the direction of Peter Johnston, Ontario Ministry of Agriculture, Food and Rural Affairs’ cereals specialist, suggest that there may be an economic advantage to applying more than this.
Their work suggests that 140-150 pounds per acre of nitrogen on soft red wheat, along with fungicides is economical. This is not a general recommendation yet. Research will continue this year to validate these rates. But this year consider doing some strips at up to 130-150 pounds of actual nitrogen.
There is similar work from Michigan showing a yield advantage using up to 140 pounds per acre of actual nitrogen. This research was without fungicides.
As far as source, there is not a big difference in yield between Urea, 28 or 32 per cent UAN. Equipment to apply and dealer preference are more important issues than product. Some growers in certain areas have found a response some years to adding about 10 pounds per acre of sulphur as ammonium sulphate.
Whatever the source or rate you pick once your wheat starts to green up it is time to apply nitrogen. And if you have not spread red clover yet, you can still expect a catch if spread by April 10-15. BF