Content by Adam Varenhorst

South Dakota Overwintering Bean Leaf Beetle Predicted Mortality: 2024-2025

Each year we evaluate the overwintering success of bean leaf beetles in South Dakota. For adult bean leaf beetles that successfully overwintered, emergence will begin in the spring and they will move into soybean fields.

Alfalfa Weevils Are Active in Some Parts of South Dakota

Degree day accumulations indicate that alfalfa weevil larvae should be active throughout South Dakota.

Alfalfa Weevil Activity Prediction Update: May 22, 2025

Degree day accumulations for alfalfa weevil larvae indicate that third to fourth instar larvae should be active in fields throughout South Dakota.

Black Grass Bug Activity Ramping Up

Black grass bugs feed on fresh green growth, which can result in stunted plants and decreased forage quality. Monitoring and potential management of black grass bugs will be of increased importance this spring, especially if drought persists.

South Dakota Grasshopper Prediction for 2025

In 2025, it is likely that grasshopper populations will once again reach levels capable of causing issues in some areas of the state. Scouting should begin shortly after planting in areas where they were problematic in 2024 and continue throughout the growing season.

Spring is here, and so are the ticks!

As spring continues to bloom, more arthropods will begin to emerge from winter dormancy. Ticks are among the first to appear, and statewide reports have already been flowing in.

Sunflower Moths Causing Problems

While scouting late-planted sunflowers two weeks ago, there were increased observations of sunflower moth caterpillars in the heads that were later than the rest of the field. Sunflower moths are best managed as moths or early instar larvae.