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Insect & Pests

All Insect & Pests Content

Cream colored larva that has an accordion shape and a brown head in the stem of a sunflower.

Dectes Stem Borer in South Dakota Sunflowers

Factsheet covering Dectes stem borer in sunflowers.

Swarm of mosquitoes.

West Nile Virus Update: October 16, 2025

As of October 16, 2025, the South Dakota Department of Health reported 86 human cases of West Nile virus from Aurora, Beadle, Bon Homme, Brookings, Brown, Charles Mix, Clay, Codington, Corson, Douglas, Grant, Gregory, Haakon, Hamlin, Hand, Hughes, Hutchison, Hyde, Lawrence, Lincoln, Marshall, Meade, Miner, Minnehaha, Pennington, Roberts, Sanborn, Spink, Stanley, Todd, Union, Walworth, and Yankton counties.

Northern Corn Rootworms on sunflowers, zinnias, and dahlia flowers.

Corn Rootworm Presence in Cut Flowers

Multiple cut flower farms in Eastern South Dakota have reported corn rootworms on a variety of crops, including sunflowers, zinnias, and dahlias. Careful attention to species present, their timing, and the damage they cause can help inform integrated pest management strategies.

Yellowjacket feeding on decaying produce.

Yellowjackets: Swarming decaying produce or garbage near you

Fall is here, and if you have a garden, fruit trees, or outdoor dumpsters, you are likely to encounter yellowjackets in search of food. Learn some expert tips to avoid getting stung this fall.

Swarm of mosquitoes.

West Nile Virus Update: September 26, 2025

As of September 26, 2025, the South Dakota Department of Health (SD DOH) reported 74 human cases of West Nile Virus from Aurora, Beadle, Bon Homme, Brookings, Brown, Charles Mix, Clay, Codington, Corson, Douglas, Grant, Gregory, Haakon, Hamlin, Hand, Hughes, Hutchison, Hyde, Lawrence, Lincoln, Marshall, Meade, Miner, Minnehaha, Pennington, Roberts, Sanborn, Spink, Stanley, Union, Walworth, and Yankton counties.

Multicolored Asian lady beetle, female mosquito, and boxelder bug.

Insects Are Being a Nuisance This Fall

The weather is changing, and many of us are noticing an uptick in the nuisance bites caused by several insects. The continued warm weather is going to increase the activity of all insects, including the ones that are causing us displeasure.

Multi-rotor drone used for spray, spread and seeding

Required Licensing For Applying Pesticide Using Spray Drones

Fact sheet for South Dakota stakeholders wanting to get certified to apply pesticides with a spray drone.

Swarm of mosquitoes.

West Nile Virus Update: September 10, 2025

As of September 10, 2025, the South Dakota Department of Health (SD DOH) reported 59 human cases of West Nile virus from Beadle, Bon Homme, Brookings, Brown, Charles Mix, Codington, Corson, Grant, Gregory, Hamlin, Hand, Hughes, Hutchison, Hyde, Lawrence, Lincoln, Marshall, Meade, Miner, Minnehaha, Pennington, Sanborn, Spink, and Walworth counties.

A female Hessian fly on a blade of wheat.

Hessian Fly: Winter Wheat Planting Date Considerations

As winter wheat planting rapidly approaches, there are many factors that should be considered. One of those factors is choosing a planting date to avoid Hessian fly issues. Learn some expert tips for selecting a safe planting date for your region.

Green and brown grasshopper with two yellow lines that originate on the head and meet on the abdomen.

Monitor Emerging Winter Wheat for Grasshopper Populations

Large grasshopper populations have been observed in many areas of South Dakota. It is important to scout winter wheat fields for grasshoppers before and after planting, especially in areas where large populations have been identified.