Tar spot, a fast-moving corn disease, is spreading across key Corn Belt states, with confirmed cases in Nebraska, Iowa, and Kansas. AgroLiquid National Agronomist Stephanie Zelinko urges growers to scout fields regularly. “We already have confirmed cases, but because it moves by wind, it’s spreading to other areas rapidly,” said Zelinko. “It needs moisture and certain temperatures to activate, so scouting is important to understand what’s going on in your field and catch it early.” Zelinko also emphasizes the role of plant nutrition in boosting disease resistance, particularly potassium. “Potassium is directly connected to plant health—it strengthens cell walls and enhances disease resistance,” she said. “While potassium won’t cure tar spot, having enough of it going into reproductive stages makes the plant stronger and better able to resist stress and disease.” She recommends pairing fungicides with nutritional products in tank mixes to improve crop protection and reduce application costs.
