News

Corn tar spot could be major disease issue

A field crop pathologist is encouraging farmers to report signs of corn tar spot as soon as possible.

“It’s here, it’s overwintering on the debris that we have.”  

Martin Chilvers with Michigan State University says the fungal disease was epidemic last year around Lake Michigan after first appearing in the U.S. in 2015.

“Northern Illinois, northern Indiana, southeastern Wisconsin, and just touching eastern Iowa, and Ohio as well so we’ve got it in a six-state region that it’s been confirmed in.”

He’s fully expecting corn tar spot to be even more widespread this year which can cause up to 50 bushes losses.

“These early moisture events certainly may get things started, but it’s really going to be dependent on rainfall through July and August when we’ve actually got a canopy.”

The disease causes major lodging and lowers quality in corn silage as well.

Corn tar spot was first found in July last year and Chilvers says farmers should look for raised, black fungal structures on corn leaves.  He says the best time to spray for the disease is during tasseling and early harvest might be necessary.