Later this year, you’ll probably have to decide whether or not to try to enhance wheat protein levels.
The premium for protein usually is based on what the protein level of the crop might be. If the protein is anticipated to be lower, a higher discount for lower than 14% protein will be imposed and a greater premium for higher protein will be offered.
If you decide to try to increase protein, the most efficient way to accomplish this is to apply 30 pounds of nitrogen per acre (10 gallons of UAN plus 10 gallons of water) immediately post-anthesis, or flowering, before the wheat berry starts to become milky, says Dave Franzen, North Dakota State University Extension soil specialist.
He recommends applying the product with flat fan nozzles broadcast over the plants during the cool of the day, usually from just before daybreak until it becomes hot. If the day is cloudy, and temperatures are in the range of 50 to 60 degrees F, the sprayer could likely run all day. Expect some leaf burning, but at this growth stage the burning does not contribute to yield loss — but don’t push it. Spraying all day in heat/drought-stressed wheat when temps are 90 degrees F is not a wise practice.
You can reduce the risk of leaf burning if the fertilizer supplier “melts” urea to make a urea solution.
“In most cases, low burning or no burning results from using straight urea compared to UAN. However, in 2015 in the Bismarck area and in Manitoba, fields were severely burned from urea solution application. This would probably be the result of biuret contamination of the urea used to make the solution,” Franzen says.
Biuret is a byproduct of the urea manufacturing process when the process is poorly regulated.
Although U.S. and Canadian manufacturers do a good job of keeping biuret content of urea low (less than 0.2%), the same might not be true from offshore sources, according to Franzen.
Midwest Laboratories, Omaha, Neb., (phone 402-334-7770) offers a test for biuret. There are few laboratories in the region that test fertilizer for biuret. The turnaround time for this test is three to five business days.
“There are a number of products that are slow-release urea liquid fertilizers that claim great efficiency over UAN or urea solution. Instead of 30 pounds N per acre, which is required for 0.5% to 1% protein gain, they claim that 1-3 gallons per acre (2.5 to 7.5 pounds N per acre) of their product will accomplish the same task. This is untrue,” Franzen says. “These slow-release products have no more foliar efficiency than UAN.”
Check out data on several of these products in recent NDSU studies.