Tar Spot a Growing Concern for 2023

Higher precipitation in the weeks leading to spring planting has corn growers more concerned over the tar spot fungus. The disease can reduce yields from 20 to 100 bushels per acre by reducing ear size and kernel fill. Last year’s growing season showed some reprieve thanks to dry conditions inhibiting excess fungal spread.

But while rainfall certainly is a key driver, average daily humidity is what growers should be looking at. A June 2022 Purdue University report said that cool conditions, humidity and prolonged leaf wetness fuel tar spot pressure in corn. Farmers can scout during the early weeks of summer and select naturally resistant hybrids to mitigate pressure.

Read more on tar spot concerns and mitigation here.