Kansas corn battles rising pest and disease pressure

Crop diseases and pests are taking a toll on Kansas corn. Two crop experts from Kansas State University share tips for producers dealing with cutworms and armyworms.

Kansas’ 6.4 million acres of planted corn are facing several challenges this year.

Disease pressure is taking a toll on the crop. Seven counties in northeast Kansas have reported cases of tar spot. Pests, including armyworms and cutworms, also pose a significant concern.

However, despite these concerns, the latest Crop Progress Report released by the U.S. Department of Agriculture (USDA) rated Kansas corn at 69 percent good to excellent.

Two crop experts from Kansas State University (K-State) weigh in on current conditions in the state.

Dealing with Armyworms

“Right now, the larvae that I’ve seen are relatively large, which means they have almost completed their feeding, so they’re not going to feed and they’re not going to cause much more damage,” said Jeff Whitworth, Associate Professor of Entomology at K-State.

“What you need to do is get out and monitor your yard, your crop, or whatever it is you’re worried about to see what stage they’re in,” Whitworth said. “It’s going to be different for you in a week or two. Egg laying can make a difference as far as how much longer the larvae are actually feeding. If they’re relatively large larvae — by that, I mean, an inch to an inch and a quarter — they’re not going to feed much more. So, that has a big impact on when you want to treat, if you want to treat.”

The K-State expert advises scouting for armyworms at night, as the pest is nocturnal and primarily feeds in the dark.

Dealing with Cutworms

Another corn pest of concern is the Western Bean Cutworm, which is currently active in western Kansas.

“We’ve got a lot of fields tasseling in western Kansas right now, and the Western Bean Cutworm overwinters in the soil as pupa — and about this time of year, adult moths are going to be emerging from the soil — and they’re going to be gravitating towards cornfields,” explains Anthony Zukoff, an K-State Extension Associate specializing in Entimpology.

Zukoff says that during tasseling, females lay eggs in corn fields, with caterpillars migrating to developing ears and consuming kernels, leading to a reduction in yields.

Related Stories
Lewis Williamson with HTS Commodities joined us to provide analysis on the January WASDE report and expectations for grain markets going forward.
Structural efficiency supports cattle prices and resilience — breaking it risks higher costs and greater volatility.
Market reaction was bearish for corn and soybeans, with analysts noting that abundant supplies amid tepid demand could keep price pressure on agricultural commodities.
The Farm Bureau’s honor highlights the important role farm dogs play on operations across the country, serving as dependable workers and trusted companions.
Rising adoption of GLP-1 drugs may gradually reshape food demand, with potential downstream effects on protein markets and consumer purchasing patterns.
Traders are keeping a close eye on China’s soybean purchases as markets track export sales, shipments, and progress toward the ‘magical’ 12 million ton target promised last year.

LATEST STORIES BY THIS AUTHOR:

AFBF Economist Faith Parum provides analysis and perspective on the Farmer Bridge Assistance Program—what commodity growers should know and potential remedies for producers facing crop losses where that aid falls short.
In a post to social media, Trump said Venezuela will buy American agriculture products and will use the money from oil sales to make it happen.
Federal nutrition policy is signaling a stronger demand for whole foods produced by U.S. farmers and ranchers. Consumer-facing guidance favors animal protein, but institutional demand may change little under existing saturated fat limits.
Farmer Bridge payments are being used primarily to reduce debt and protect cash flow, not drive new spending. Curt Blades with the Association of Equipment Manufacturers joined us to provide insight into the ag equipment market and the factors influencing sales.
Wed, 1/21/26 – 7:30 PM ET
University of Nebraska President Dr. Jeffrey Gold joined us to share insights on building healthy habits and improving rural health in the year ahead.
Agriculture Shows
Special 3-part series tells the story of the Claas family’s legacy, which changed agriculture forever.
From soil to harvest. Top Crop is an all-new series about four of the best farmers in the world—Dan Luepkes, of Oregan, Illinois; Cory Atley, of Cedarville, Ohio; Shelby Fite, of Jackson Center, Ohio; Russell Hedrick, of Hickory, North Carolina—reveals what it takes for them to make a profitable crop. It all starts with good soil, patience, and a strong planter setup.
Champions of Rural America is a half-hour dive into the legislative priorities for Rural America. Join us as we interview members of the Congressional Western Caucus to learn about efforts in Washington to preserve agriculture and tackles the most important topics in the ag industry on Champions of Rural America!
Featuring members of Congress, federal and state officials, ag and food leaders, farmers, and roundtable panelists for debates and discussions.