Because tar spot can develop as early as the third or fourth leaf stage, Whitlow says field scouting is especially important in determining when the corn crop should be harvested.
“One caveat is if we plant really later-maturity hybrids for that area and fungicide is applied, it will push you out of the harvest window,” explains Mark Hockel, Eagle Ag Consulting forage agronomist. “We’re not doing it to the later hybrids but to the early maturity hybrids so that they match up better. This has produced our best yielding silage the last two years on hybrids that are very early maturity.”
Overall, applying a fungicide allows corn to stay at optimal moisture levels for a longer time, helping to protect against lost yield at the same time it increases the digestibility of the crop, Hockel says.
In 2012, a drought year, University of Minnesota Extension researchers studied the effects of fungicide application on corn. Hockel says researchers found a huge response in terms of moisture use efficiency (or water use efficiency—WUE) to fungicide-applied corn.
“We’ve found that if we put fungicide on a little earlier, moisture use efficiency increases,” he explains. “In silage production, we’re looking to keep that whole plant healthy, which adds value and allows it to be more efficient with the water it contains.”
As farmers continue to push for higher yields, applying fungicide to corn increases its WUE. And on dry land, Hockel says that’s where fungicide application has some real benefits.
Download the 2023 Silage Guide
