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Adam Varenhorst

Associate Professor & SDSU Extension Field Crop Entomologist

605-688-6854

Berg Agricultural Hall 226
Box 2100A
Brookings, SD 57007

As the SDSU Extension Field Crop Entomologist Adam serves South Dakota stakeholders by addressing insect pest issues in field crops. He conducts applied research that focuses on corn, soybean, wheat and sunflower. Additionally, he assists the other extension entomologists to address questions pertaining to insect questions for the home and garden, urban insect pests and general entomology questions.

State & Regional Offices

SDSU Campus
Also by Adam Varenhorst
Green stem that is covered in light green colored aphids.

Economically Damaging Soybean Aphid Populations Detected

Soybean aphid populations continue to grow in South Dakota. This week, counts near Volga ranged from approximately 280-700 aphids per plant. Observations of these populations indicate that they are healthy and will continue to increase.

Dying patch of soybeans in an otherwise healthy field.

Scout Soybean in Drought-Affected Fields for Twospotted Spider Mites

One of the pests that typically shows up during drought conditions is the twospotted spider mite (Tetranychus urticae). Infestations of this pest were recently confirmed in Eastern South Dakota soybean and corn.

Metalic bronze green beetle on a green leaf

Japanese Beetles in South Dakota

In the last 10 years, Japanese beetle populations have remained low to absent in my garden in Brookings. However, last week I observed large aggregations of beetles feeding on smartweed that was present in my rain garden. Japanese beetles can be problematic for gardens, flowers, and trees in residential areas.