Episode 169 – Tar Spot in 2025

Tar spot concern continues to grow across Ohio as it shows up in more and more fields each year. Each year farmers and researchers wonder if this will be the season it really explodes, causing widespread economic damage. For a background on Tar Spot, check out episodes 123 and 101.

In this episode, Dr. Stephanie Karhoff updates us on the latest research and treatment recommendations for managing not only Tar Spot but Gibberella ear rot and the vomitoxin it causes. Each disease has certain weather conditions and infection timing that are critical components to successfully managing it in field. The Crop Protection Network’s disease forecasting tool can afford insight into what to look for during scouting: https://cropprotectionnetwork.org/crop-disease-forecasting.

Episode 123 – Tar Spot

If you grow or scout corn in Ohio, you have probably heard rumblings of a new disease called Tar Spot. Pictures from neighboring states to the north and west show bleak images of entire corn fields dead before their time. While researchers are still assessing the threat potential for tar spot in Ohio, it has made appearances across the state and has many farmers quite concerned. To tell us more about this new disease, Dr. Stephanie Karhoff joins us to share what she has seen and learned in her time in NW Ohio.

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