Corn Belt Agronomists Share One Word to Sum Up July’s Impact on Crop

July, perhaps the most critical month for corn development, may be over, but its full effects on the national corn crop are still to be seen. 

To understand the month’s impacts, we asked agronomists in some of the top corn-growing states to describe July in a single word, reflecting the crop’s progress, condition, and challenges in their regions. Here are their insights.

Extreme

Eric Wilson described July in Iowa as “extreme.” He’s a Wyffels agronomist who supports southern and northeast Iowa.

“July, which is typically one of the driest months, experienced a tremendous amount of rainfall,” Wilson said. 

Topsoil moisture levels in Iowa reflect the abundant precipitation. As July turned into August, all but 5% of the state’s topsoil moisture was rated adequate or surplus, USDA reported this week.

“Temperatures were also very warm, especially overnight. Humidity levels have been very high as well,” Wilson added. “This has resulted in some late season nitrogen loss, as well as easily visible foliar disease pressure in our corn fields.”

Favorable

July in Nebraska was “favorable” for the state’s corn crop, according to Syngenta agronomist Travis Gustafson. 

“July has been extremely favorable for crop growth and development in Nebraska. I don’t think I’ve seen a July as stress-free for crops in Nebraska as I saw in 2025.”

As of the latest Crop Progress report, USDA rated 79% of Nebraska’s corn good/excellent, making it some of the best reported in the country.

Gustafson shared that although the crop is looking good, he’s not sure it will translate into yield. “I have seen some tip back, and I’m not impressed with the kernel depth I’ve seen so far,” he said.

Ideal

Nick Groth, a Syngenta agronomist supporting the state of Wisconsin, described July as “ideal” for corn.

“For much of Wisconsin, July brought nearly ideal growth and development conditions for the corn crop,” Groth shared. “There was good heat for much of the month, without seeing a lot of excessive heat that can hurt the crop. We also received moisture when it was needed for much of the state.”

Wisconsin’s corn was rated highly by USDA in its latest report — less than one-fifth was in fair shape or worse, and 81% of the state’s crop was rated good/excellent.

Groth is keeping an eye out for another outcome of the ideal conditions in his state. “The high humidity and frequent moisture may also prove to be ideal for disease development, but time will tell on that as heavy disease pressure is yet to be reported,” he said.

Humid

Jared Goplen, whose territory stretches between northwest Iowa, southern Minnesota, and eastern South Dakota, described a “humid” July. 

“The humidity and heat have fueled some extreme storm events with multiple tornadoes along with some significant straight line winds and hail,” he said. 

Goplen said the storm damage has been relatively isolated, fortunately.

“In general, the amount of crop damage has been much less than anticipated considering winds in the 90mph+ range,” Goplen shared. “Thankfully, the corn is all well beyond pollination and has strong, lignified stalks along with good root development that minimized how widespread root lodging and greensnap was from the storms.” 

Like Groth, Goplen predicted conditions may prove favorable for disease. “This humidity has also provided an environment where most any corn disease can be found. I think disease could become a major issue in the coming weeks if weather continues to be conducive to development,” he said.