Corn Insects

Western corn rootworm beetle feeding on a leaf of corn

Western Corn Rootworm Beetles Emerging, Time to Scout July 9, 2019

Western corn rootworm beetles began emerging in southeast and south central Nebraska and will feed on corn leaves until silks, their favored food, emerge. Beetles will emerge somewhat later in northeast and western Nebraska.

Crop progress and conditions for corn from the USDA National Agricultural Statistics Service indicating predicted timing for corn growth stages (2019).

Using Degree-Day Models to Predict Western Bean Cutworm Flights June 21, 2019

With late planting, slow emergence, and cooler summer temperatures affecting corn development, will corn be spared from western bean cutworm damage in 2019. Unfortunately, models indicate WBC growth is also delayed. See a table of predicted dates for 2019 WBC flights in Nebraska and surrounding states.

Example of bioassay used for monitoring ECB susceptibility to Bt protein

First ECB Resistance to Bt Corn Reported in Canada May 22, 2019

The first case of field-evolved resistance of European corn borer (ECB) to Bt transgenic corn has been reported in Canada. What does this mean for Nebraska corn farmers and how can they help maintain resistance here?

Avoiding Injury from Seed Corn Maggot April 26, 2019

A new pest management resource for the seed corn maggot predicts fly development based on accumulated growing degree days. A new map, updated daily, shows degree days at multiple sites.

Figure 1. Nebraska's Joe Louis with a collection of leaves infested by corn-leaf aphids. Louis and his colleagues have found that spraying a corn plant with one of its own defensive compounds might reduce aphid colonization by as much as 30%. (Photo by Craig Chandler, University Communication)

Experiments Underscore Overlooked Aspect of Defending Corn from Pest March 4, 2019

Spraying a corn plant with one of its own compounds — 12-oxo-phytodienoic acid, or OPDA — can help deter the virus-carrying, pollination-disrupting insect known as the corn-leaf aphid.

The Biology and Management of Ear-Feeding Lepidopteran Pests of Corn in Nebraska January 9, 2019

A guide to Identification and management of European corn borer (Ostrinia nubilalis), western bean cutworm (Striacosta albicosta), corn earworm (Helicoverpa zea), and fall armyworm (Spodoptera frugiperda).

Western corn rootworm beetles feeding on a corn leaf — Figure 1. Damage to corn leaf caused by western corn rootworn. (Photo by Robert Wright)

Western Corn Rootworm Beetles Emerging, Time to Scout June 27, 2018

Corn rootworm beetles started emerging in southeast and south central Nebraska and scouting is recommended. An average of 5-10 beetles per ear usually can seriously affect pollination.

Figure 1. Japanese beetles will first feed on the leaves of soybean (left) or corn. In corn they'll move to the silks (right) when they become available. (Photos by Justin McMechan) — Figure 1. Japanese beetles will first feed on the leaves of soybean (left) and corn. In corn they'll move to the silks (right) when they become available. (Photos by Justin McMechan)

Scout Corn and Soybean for Japanese Beetles June 25, 2018

Japanese beetles are emerging in eastern Nebraska and will continue to emerge for the next couple of weeks. As numbers will be highest in field margins, growers are advised to scout across the whole field before determining the need for treatment.