Tar Spot is not going away in Missouri as it continues its spread into more states.
“Tar spot is definitely coming in hot,” says Kaitlyn Bissonnette, MU Extension’s state field crop plant pathologist, at the MU Crop Management Conference. She says tar spot is confirmed in eight northeast Missouri counties but anecdotal evidence means it’s probably across the entire northern part of the state.
She says Missouri is set up for tar spot development, “Partially because we have moderate temperatures, high relative humidity, we have seven-plus hours of leaf wetness at night.
