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Wheat Insects

All Wheat Insects Content

wheat field

Wheat

The SDSU Extension team provides unbiased, research-based information to help wheat growers make decisions to improve yields and profits.

aerial view of South Dakota farm and surrounding land

Crops

During the growing season, SDSU Extension provides weekly production recommendations.

Green wheat leaves with yellow streaks throughout.

Wheat Streak Mosaic Virus Complex: Breaking the Green Bridge

As wheat harvest proceeds, it won’t be long until winter wheat planting is underway in South Dakota. To effectively reduce wheat streak mosaic virus, it is important to manage the green bridge effect to slow spread of disease in newly emerging wheat fields.

Wheat plants infected with wheat streak mosaic virus.

Volunteer Wheat and Kochia Management With Herbicides Will Likely Require Two Passes

Wheat curl mites, which carry wheat streak mosaic virus, use volunteer wheat and grass weeds as secondary hosts to infest recently planted winter wheat crops. Therefore, effective management of these plants before winter wheat planting is critical.

Multiple grasshoppers feeding on a corn ear.

Grasshopper Populations Continue to Cause Issues in South Dakota

Recent reports of crop loss along field edges indicate that grasshopper populations in some areas of South Dakota are well above threshold. Unfortunately, crops are often the target of these moving populations.

True armyworm caterpillar on a corn leaf.

Reports of Pyrethroid Failures for True Armyworm Caterpillar Management

True armyworm caterpillars reached thresholds in oats and wheat in many areas of South Dakota recently. Management efforts to reduce populations had varying levels of success, with SDSU Extension receiving numerous reports of pyrethroid insecticide failures.

Dark green and tan curled caterpillars with an orange stripe along their sides.

True Armyworm Caterpillars Are Active in South Dakota Wheat

We have received a few reports of true armyworm caterpillars in wheat that are heavily feeding on the leaves. The big concern with these pests is that they will also clip wheat heads prior to harvest, so scouting is necessary to ensure that they don't cause yield losses.

U.S. Environmental Protection Agency offices in Washington, D.C.

Update on Chlorpyrifos Use in South Dakota

As of June 30, 2025, the labeled uses for chlorpyrifos products for food and feed are limited to alfalfa, soybean, and wheat in South Dakota. Chlorpyrifos can no longer be used to treat sunflowers.

Redlegged and differential grasshopper nymphs.

Grasshoppers Are Showing up in Large Numbers in Eastern South Dakota

While scouting spring wheat in Brookings County this week, we noticed grasshopper nymph populations that were close to threshold.

Green aphid with black cornicles and black patterns on legs.

Aphid Populations Continue To Increase in Wheat

English grain aphid populations are continuing to increase in wheat. With increasing pressure, it is important to scout wheat fields to ensure that the populations do not cause yield loss.