What's Happening?
As of July 7, 2026, tar spot, a significant corn crop disease, has been confirmed in several Midwest states, including Iowa, Kansas, and Missouri. However, it has not yet been detected in Kentucky. Disease forecasting suggests a low risk for rapid development
of tar spot in Kentucky, even if it were to be detected. Corn hybrids with strong resistance to foliar diseases are less likely to benefit economically from fungicide applications, whereas susceptible hybrids in continuous corn systems face a higher risk due to the survival of fungi in crop residue. The choice of fungicide is crucial, with research indicating that products containing multiple fungicide classes are more effective than those with a single active ingredient.
Why It's Important?
The presence of tar spot in the Midwest poses a significant threat to corn yields, which are vital to the U.S. agricultural economy. The disease can lead to substantial yield losses, affecting farmers' profitability and potentially impacting corn supply and prices. In Kentucky, the low risk of rapid disease development offers some relief to local farmers, allowing them to focus on other management practices. The choice of fungicide and hybrid selection are critical decisions that can influence economic returns, highlighting the importance of strategic planning in agriculture. The situation underscores the need for ongoing research and monitoring to mitigate the impact of crop diseases.
What's Next?
Farmers in affected areas are advised to continue monitoring their fields and make informed decisions regarding fungicide applications. In Kentucky, growers should remain vigilant and scout fields regularly to identify any signs of disease early. The effectiveness of fungicide applications depends on timing, with the best results typically seen when applied at tasseling through early silking stages. As the season progresses, farmers will need to balance the costs of fungicide applications with potential yield benefits, considering current market conditions and commodity prices.
