Damon L. Smith, Extension Field Crops Pathologist, University of Wisconsin-Madison
Treating field corn, for grain, with fungicide has become a common practice in the Midwest. With so many fungicide programs and formulations, and the re-emergence of yield-limiting corn diseases, like northern corn leaf blight (NCLB) and gray leaf spot (GLS), foliar fungicide application has demonstrated an ability to reduce foliar disease severity and increase grain yield under some circumstances.
How do I know if disease is active at the time I want to spray? While I hate talking about threshold levels for managing disease, it can be helpful in your decision making process to know what might be severe. While scouting look in the lower portion of the canopy… (read more)