Delay Wheat N Applications Until Growth Stage 5

EDWARDSVILLE, ILL.

    As we approach mid-February, wheat producers begin to think about spring nitrogen applications. Many growers prefer to get their nitrogen applied as early as possible, while the weather is cold and fields remain frozen. While these early applications often result in fewer wheel tracks in the field, they may not provide the greatest yield potential for the expensive fertilizer dollars invested.

   Last fall’s late harvest delayed wheat planting, which resulted in the crop entering winter dormancy in a much less than ideal condition here in southern Illinois. Although most stands were relatively uniform going into winter, the lack of fall growth resulted in stands with greatly reduced tiller numbers and a lot of bare ground showing. Much of this winter has been colder than typical in recent years, and marked by a lack of insulating snow cover. Then, to add insult to injury, the storm in late January covered many of the southern wheat-producing counties in various amounts of sleet and ice.

    Unfortunately, until temperatures warm up and the crop breaks dormancy, it is going to be difficult to assess the survival and vigor of the crop. While early N applications may potentially increase tillering somewhat, there remains the risk of applying expensive N on a field that may not be worth salvaging.

   Ongoing research, conducted by Steve Ebelhar at the U of I Dixon Springs Agricultural Center and other locations, indicates that highest wheat yields are normally obtained by delaying N applications until wheat reaches Feeke’s Growth Stage 5. This is after tillering is completed but before leaf nodes are present, and typically occurs sometime in early to mid- March. An added advantage to waiting this year is that it will allow time to evaluate the condition of each field to determine whether the field is even good enough to keep.

   Ebelhar will present detailed results from his research on nitrogen rates, timing and sources for wheat at this year’s Illinois Wheat Forum on Monday, February 23, 8 a.m. to 3:20 p.m. at the Holiday Inn, Mt. Vernon. The registration fee is $15 for Illinois Wheat Association members and $25 for non-members. Other topics for this year’s Forum include an update on wheat disease management, maintaining wheat quality after binning, and a grain marketing outlook. Certified Crop Adviser credits will be available. For more details about the Wheat Forum, check the “Events” section of the SI Agriculture website, http://web. extension.uiuc.edu/regions/ag. Δ

Robert Bellm is University of Illinois Extension Educator, Crop Systems, at the Edwardsville Extension Center.