MONMOUTH, Ill. — Along with the first frost date and how many acres of corn actually got planted, there’s one more “million-dollar question” that farmers are asking this year.
“Should you be spraying your corn?” Rachel Willis, technology development rep for Asgrow DeKalb in west-central Illinois, received a round of nods and smiles when she guessed that question correctly.
Willis was presenting a session on corn diseases at the recent Bayer Learning Center field day in Monmouth.
Some factors may make that decision easier in a year filled with uncertainty.
“This April-planted corn, with this corn, it’s an easier decision. You probably have some pretty good yield potential out there,” Willis said.
“We might be kind of selling ourselves short on some of that. It had a pretty rough start, but I think we have some pretty good yield potential.”
Jim Donnelly, Asgrow DeKalb technical agronomist in northern Illinois, sought to correct some of the misinformation about fungicide application effects on maturity, drydown and grain moisture.
Donnelly said farmers might be loathe to spray corn planted late, particularly in June, considering that the June-planted corn may never make it to maturity anyway.
“It is very much delayed, but stands are good and overall potential might surprise some people on this June-planted stuff, especially if we get GDUs and very good conditions,” Donnelly said.
Donnelly said that while fungicide may slow drydown, it can thus add to yield.
“It slows the drydown a little because it keeps the plant healthier, which is a good thing, because it’s adding more fill,” he said.
The benefit this year is a fungicide application could protect a late-planted crop from a variety of diseases, like gray leaf spot and southern rust, which could wreak more devastation on younger corn.
“I think, most importantly, those later planted dates are going to be more susceptible just to overall increased disease pressure. Whether we are talking about southern rust or it’s gray leaf spot, that June-planted stuff is going to be filling longer and later on in the season when there’s a lot more inoculum flying around,” Donnelly said.
Willis emphasized the need, especially this year when growth and disease progress can vary within single fields, for crop scouting.
“This is really a year to go scout your fields and know what’s going on. Take your best guess at yield potential, but also look at your disease pressure because that is really going to help with that fungicide decision,” she said.