Tar spot continues to be a growing concern for corn producers across the Midwest. Research has found that tar spot can overwinter on infested corn residue, increasing crop infection risks and leading to questions on managing the newer corn disease.
A timely fungicide application will help, but there is no hybrid that is completely resistant to tar spot.
“Fungicide won’t save a susceptible hybrid from tar spot,” said Matt Vandehaar, Pioneer Field Agronomist. “You can’t fungicide your way out of tar spot.”
Vandehaar says that hybrid selection is critical and that now is the time to be having conversations and gathering data from your seed salesman.
“Ask your seed salesman to give you their tar spot score,” says Vandehaar. “If they don’t have anything published, what are they verbalizing? Do they have examples of that hybrid and how it did in a high tar spot pressure area within the last two years or somewhere locally? Certainly we can wait for tar spot all we want, but if you don’t have that disease show up, you may not get that score in a certain hybrid—especially a new hybrid.”
On the fungicide front, many farmers used to wait and make an in-season decision on whether to apply fungicide. Ron Geis, market development specialist for Corteva, says that has largely shifted as growers have found that fungicide applications are more than paying for themselves.
“Tar spot is just another reason to use full foliar fungicides, but the foliar fungicides that provide plant health benefits like the Aproach® Prima—it does give you a healthier plant that stands better at harvest,” says Geis. “It also controls problematic diseases. When we have moisture, that’s when we have really good yields and that’s when we have our diseases. That’s when we can justify the use of a fungicide even better because we want to keep that top-end yield, manage the disease, and be able to harvest a crop that’s standing. We can put it all into the bin, it all works together with some good management.”
You can plan now to start tackling tar spot for next year’s growing season with your local Pioneer representative by visiting pioneer.com/FindMyRep.
