The Indiana Certified Crop Adviser panel discussed on June 2 the outlook for corn diseases this year, offering guidance on scouting and fungicide application strategies. The panel included Betsy Bower, Purdue Extension senior research associate; Abby Horlacher, Nickel Plate Consulting; Brian Mitchem, Farmer 1st Agronomy Consulting Services; and Dan Quinn, Purdue Extension corn specialist.
Bower said, “Every year is different. Some years, the stars align for infection by tar spot. Last year, we had spores and the right environment for southern rust to explode in some areas of Indiana.” She advised scouting at least once a week starting around V12-V15 stages to monitor foliar diseases that impact grain fill. Bower also recommended monitoring southern regions using resources like the Crop Protection Network.
Horlacher highlighted digital tools such as Tarspotter and the Crop Protection Network’s Crop Risk Tool to identify high-risk diseases. She said fields with consistent disease pressure should be prioritized: “Scouting should begin about four to seven days after rainfall events while also monitoring disease forecasting tools and local field reports.” Horlacher urged reviewing fungicide labels closely when planning applications.
Mitchem noted that although southern rust traveled further north last year than before, it does not overwinter in Indiana: “Tar spot does overwinter and remains the most impactful disease for most in the state.” He emphasized weekly scouting and adjusting based on area infection reports. Mitchem said fungicides are most effective when applied preventatively during key reproductive stages.
Quinn explained that environmental conditions largely dictate which foliar diseases appear each season: “Southern rust is unique as it can ‘blow up’ from the South depending on the year…pay attention to pressures in Southern states.” He recommended weekly scouting approaching pollination stage and making fungicide passes at R1 or R2 stages depending on disease timing.
Farmers can access tracking tools through organizations such as Farm Progress, which supports agricultural communities by offering resources like market updates, educational programs, regional publications, digital platforms, market analysis tools, and event organization including Farm Progress Show and Husker Harvest Days—all aimed at aiding farmers nationwide, according to the official website of Farm Progress.
