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Insect & Pests

All Insect & Pests Content
White larvae in brown soybean pith.

Dectes Stem Borer Observed in Soybean

We have received an increased number of Dectes stem borer reports in South Dakota soybean, and we are currently scouting to determine which counties have the highest risk for Dectes stem borer issues.

Mottled brown grasshopper nymph sitting on a green leaf. Wing pads are easily observed in the image.

Grasshoppers Continue to Be an Issue During 2023

We have received numerous reports of very large populations of grasshopper nymphs in June. Before management action is taken, it is important to determine what stage observed grasshoppers are at.

Patch of phlox with white, speckles throughout the leaves due to spider mite feeding.

Spider Mites on Garden Phlox

During warm, dry weather, spider mites are a common pest of phlox, causing speckling, bronzing, and yellowing on leaves due to feeding behavior. Learn how to identify and manage infestations before they impact your garden.

Gray beetle on a green alfalfa leaf.

Blister Beetles Are Active in South Dakota

A common pest of alfalfa, blister beetles pose serious health risks to livestock if their bodies are consumed along with alfalfa bales. Learn some important considerations for identifying and managing blister beetles before harvesting alfalfa this growing season.

Numerous nymph grasshoppers feeding on corn.

Large Grasshopper Populations Detected in South Dakota

Very large populations of grasshoppers have been detected in southeastern South Dakota. Although these grasshoppers aren’t causing serious defoliation in crops yet, there is the possibility that they will as the season progresses.

Bean leaf beetle feeding damage on young soybean plants.

Time to Start Scouting for Bean Leaf Beetles

With soybean emergence underway, the next concern is early-season bean leaf beetle defoliation. Learn some expert tips for scouting and managing them before they impact yields.

Green beetle larvae with a white stripe running down its body.

Alfalfa Weevil Activity Prediction Update: June 1, 2023

Throughout much of the state, enough degree days have accumulated for alfalfa weevil larvae to begin pupating. Scouting should continue until larvae are not observed.

Small pale green leafhopper on a green alfalfa leaf.

Potato Leafhoppers Arriving Early This Season

Potato leafhoppers are already active in alfalfa due to prevalent south winds and above-average temperatures. Learn some tips for scouting and managing them before they impact yields.

Green beetle larvae with a white stripe running down its body.

Alfalfa Weevil Activity Prediction Update: May 25, 2023

Last week we confirmed both alfalfa weevil adult and larval activity in alfalfa. Scouting should continue, as the forecasted warm weather will promote alfalfa weevil larvae feeding.

Purple-brown caterpillar with orange head on a green corn leaf.

Common Stalk Borer Activity Estimate: May 25, 2023

Common stalk borer caterpillars are a frequent early-season pest of corn, and their hatching and movement can be estimated by using degree days. See our latest scouting and management recommendations based on observations from around the state.