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Insect & Pests

All Insect & Pests Content

Left Mosquito specimen with dark coloration. Right: Mosquito specimen with white band on its proboscis.

Mosquitos to Watch for in South Dakota

After many areas in South Dakota experienced heavy rainfalls, mosquitos are now a major issue. Learn which species are most common throughout the state and which carry the highest risk for West Nile Virus.

A hand holding a brownish gray moth with a valley of green grass and trees in the background.

Army Cutworm Migration Swarms Detected in Western South Dakota

Mass populations of army cutworm moths are being reported to entomologists at South Dakota State University. Thus far, these migratory swarms have only been observed in far western South Dakota, particularly within the Black Hills.

Closeup of a set M-44 device.

Private Applicator Endorsements for M-44 Devices, Fumigants, and Aerial Applications

Recent changes to South Dakota private applicator pesticide regulations have impacted the requirements to use M-44 predator-control devices, fumigants, and to apply pesticides from aerial vehicles.

Small moth with orange, black, and white markings.

Monitor Soybean for Soybean Tentiform Leafminer

In 2022, researchers detected soybean tentiform leafminer in McCook, Minnehaha, and Moody counties in South Dakota. The extent of the distribution of this pest in South Dakota is unknown and is currently being investigated.

Western bean cutworm caterpillar on corn.

Western Bean Cutworms Detected in South Dakota Corn

Western bean cutworm caterpillars have been reported in South Dakota corn. This pest can cause yield loss by feeding on the tassels, silks, and ears. In addition, ear feeding activities increase the likelihood of secondary diseases and mold growth on the ear.

Green plant with evidence of honeydew and an aphid colony.

Aphids Infesting Corn in South Dakota

Aphid populations are taking off in some southeastern South Dakota corn fields. The two aphid species that are commonly observed in corn include the corn leaf aphid and the bird cherry oat aphid.

Red-brown colored weevil with bent antennae originating on the elongated mouthparts.

Is it Time to Spray Red Sunflower Seed Weevils?

Red sunflower seed weevil adult activity is well underway on sunflowers in South Dakota. Even though the red sunflower seed weevil numbers are down, we are still observing populations in South Dakota that are above threshold.

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.