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Wheat Insects

All Wheat Insects Content

United States Environmental Protection Agency logo.

Cancellation of Several Neonicotinoids

On May 20, 2019, the United States Environmental Protection Agency announced the cancellation of registrations for 12 products that contain neonicotinoid insecticides. The cancellation of the product registrations was voluntarily requested by the companies that had registered the products.

Small green insects on a wheat plant.

Scouting Winter Wheat for Aphid Pests

Although we cannot predict aphid pressure in winter wheat, there are measures that may be taken to reduce the risk associated with these insects.

A small brown insect on a green blade of wheat

Scouting Winter Wheat for Mite Pests

Winter wheat planting is underway in South Dakota. After wheat emergence, it is important to scout for brown wheat mite and wheat curl mite populations.

Grain storage bin.

Steps to Prevent Stored Grain Infestations

As wheat harvest is underway it is important to ensure that grain bins are prepared in the best possible manner to prevent insect infestations. There are seven steps that can be taken to help reduce the chances of having infested grain.

: Gray caterpillar with dark markings, white splotches and a white stripe running down the middle of its back.

Monitor Alfalfa for Cutworm Activity

During the spring, there are a lot of insects to scout for in alfalfa. One pest group that should be focused on right now are cutworms. There are a couple of cutworm species that are active earlier in the season than others.

A small black bug with tan margins on the wings. This insect is resting on a blade of grass that is green with white spots.

Be on the Lookout for Black Grass Bugs

It’s time to begin scouting pasture and wheat for the presence of black grass bugs. Last year, we saw the highest populations in areas of Central and Southwestern South Dakota. If left untreated, black grass bug populations tend to increase year after year.

Brown wheat plants that have obvious feeding injury to them due to cutworm caterpillars.

Time to Start Scouting for Cutworms in Winter Wheat

Eventually, South Dakota will warm up. The warmer temperatures will increase insect activity, including pests. For wheat, a couple of early season pests that may already be active are the army cutworm and the pale western cutworm.

Green wheat with many green stink bugs present on it.

Say’s Stinkbug Present in Western S.D. Wheat: Do I Spray?

While looking at winter wheat at the new SDSU West River Research Farm near Sturgis, we came across some very large stinkbug populations in a few areas of the field. The stinkbugs we observed were the Say’s stinkbugs. Although stinkbugs have the potential to reduce wheat yields, this is attributed with feeding that occurs between the late boot and milk stage.

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

Watch for True Armyworms in Wheat

This week we observed some true armyworm caterpillars in winter wheat fields. The caterpillars were still relatively small, which means they will continue feeding for some time. So far, the true armyworm caterpillars were still feeding on the leaves of the nearly mature wheat, but they have the potential to also clip heads off of the plants.

A small black bug with tan margins on the wings. This insect is resting on a blade of grass that is green with white spots.

Black Grass Bug Activity Expected in Coming Weeks

Spring green-up is the time to be watching for black grass bug activity. Large populations of this early-season pest can cause severe damage to pasture (up to 90% forage reduction) and infest the edges of wheat fields.