August 3, 2011

Hot weather affects Iowa corn's quality

Iowa's corn crop is affected by the hottest July since 1955, and farmers are concerned that it will be difficult to get a top yield.

Iowa State University meteorologist Ellwyn Taylor said that "with heat and humidity, the likely US corn yield is likely to be about like last year, at 153 bushels per acre." That was almost 7% below the 2009 yield.

The USDA in mid-July forecast this year's national corn yield at 158 bushels per acre.

Iowa farmers say the corn crop may appear impressive, but the heat is taking its toll.

"We're a little concerned. The pollination hasn't been that good," said Jerry Peckumn, who farms in Greene county. "The crop looks good from the road, but the heat has reduced the fill of the kernels. It will be hard to get a top yield."

Iowa State University agronomist Roger Elmore said warm nights have reduced the kernel size in the ears. Elmore also said that warm nights and very dewy conditions are breeding more disease problems in Iowa's corn, particularly Goss's wilt and grey leaf spot.

Agronomist Bob Streit of Boone said, "We're seeing cases of Goss's wilt show up in the fields in west-central and east-central Iowa. There's definitely a decline in the quality of the crop. We'll see some yield reduction."