When should you apply nitrogen on a corn crop and how much? That question consumes countless hours every year for corn growers, researchers, and agronomists.
Seven years ago, Rodney, Ont., grain farmer Mike Miller, like many growers, was also playing the guessing game. But that all changed when he bought a self-propelled sprayer and started looking for ways to fine-tune his nitrogen strategy.
On this episode of The Sharp Edge, Miller and Maizex agronomist Greg Stewart look at how Miller has built an “intelligent approach” to delivering timely nitrogen to his corn crop. The key to his program is the ability to lay down UAN 28% as a dribble band at the bottom of the corn row in a June 15 to July 15 application window.
In-season rainfall is a key factor that Miller wants to manage with this approach. Before switching to the dribble band, he was seeing severe late-season nitrogen deficiencies on his farm’s sandy soils and notes how he has applied research from now-retired University of Guelph researcher Bill Deen on the impact rainfall can have on nitrogen availability.
Deen’s research can be summed up quite easily: the more rain you get, the more nitrogen you should add. His work indicated that corn growers should apply 115 lbs of nitrogen upfront and then apply an additional 25 lbs for every inch of rain received between June 15 and July 15. (Story continues after the video.)
Miller has embraced this philosophy and in 2021 was well-positioned to meet his crop needs with dribble application after Mother Nature turned on the tap in late June and delivered 12 inches of rain to his farm through July.
In the video, Miller shares how he uses a nitrogen stabilizer to protect against volatilization and leaching. He and Stewart also discuss how the high-clearance spraying option delivers flexibility, allowing him to move nitrogen management out of his weed control spray window.
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