For a couple of weeks in July, oppressive heat and humidity covered much of Kentucky.

That, coupled with a lack of rain, has caused corn in some areas of the state to have poor pollination rates and grain fill problems.

During that period, temperatures exceeded 95 degrees most days with heat indices as high as 117 reported in some parts of the state.

“We had a wet spring so that threw the corn crop behind schedule,” said Tom Priddy, University of Kentucky College of Agriculture meteorologist. “When it came time for corn’s reproductive stage, it dried off, and we were hit with oppressive heat.”

Western counties along the Tennessee border and the Purchase Area are some of the hardest hit for both temperatures and lack of rainfall.

Producers in these areas, as well as those in other places with below-average rainfall, should scout their crop for developmental problems, said Chad Lee, UK grain crops Extension specialist.

“From the outside looking in, the crop looks really good, but producers need to go into the fields and look at the ears, because we’re seeing poor pollination and seed set,” Lee said.

“If producers find developmental problems, they may want to schedule that field for an early harvest or make other marketing decisions.”

Last rain in June

With the exception of some areas getting a few isolated showers, Todd County, located on the Tennessee line, hasn’t had a significant rainfall event since the end of June, said Curt Judy, the county’s agriculture and natural resources Extensionagent. But they have had the heat.

“It’ll definitely hurt us. There’s no question about it,” he said.

Like Todd County, Graves County had oppressive heat, but they, as well as other Purchase Area counties, received a substantial rain the weekend of Aug. 6.

“We had pollination, but we didn’t have enough moisture when we needed it to fill the ears,” said Kenny Perry, Graves County agriculture and natural resources Extension agent.

“A lot of farmers call it ‘tip back’ because there’s nothing on the upper 3 to 4 inches of the ear.”

Up until the oppressive heat sat in, Graves County was on track to have one of the county’s largest corn crops ever, Perry said. While that looks like it won’t happen now, he said the county should still have a decent harvest.

“Like last year, yields could vary widely depending on the crop’s location in the field, and within the county, as some areas got more rain than others,” he said.

“Higher areas with less soil moisture will likely yield less than normal, while lower areas will likely yield higher. Overall, I’ll think we’ll have an average-yielding year.”

While the majority of the state’s corn is past the pollination stage, soybeans are still blooming and setting pods and could still have really good yields with a little help from Mother Nature.

Cooler temperatures are expected for much of the state this week. This could help finish corn grain fill, but likely will be more beneficial for soybean development and yields, Lee said.