A Corn Fungus From the Southern U.S. Is Found Across Iowa, Putting Yields at Risk

By Rachel Cramer

A fungus that attacks corn has spread to over 40 Iowa counties.

Southern rust creates reddish-orange patches on the tops of corn leaves. This blocks photosynthesis, which weakens the plant and can reduce yields. Severe cases in Florida reported losses up to 45%.

“It's unlikely that we would see yield losses that significant here in Iowa, but there is potential this year to see more yield loss than we would see in a usual year,” said Meaghan Anderson, an extension field agronomist with Iowa State University.

She added that this isn’t the first time southern rust has been found in Iowa. But it was detected earlier this year with reports coming in mid-July. The disease is also much more widespread.