Content by Philip Rozeboom

Two pictures of green soybeans with a blue sky in the background.

Strong, Effective Herbicide Programs Can Be Complimented With Narrow Row Spacing

While strong herbicide programs will result in effective weed management, a cultural tactic, such as row spacing can result in a complementary increase in effectiveness.

Three bean leaf beetles. From Left: Brown beetle with black spots on a green leaf. Yellow beetle with black spots on a green leaf. Red beetle with black spots on a green leaf.

Bean Leaf Beetles Showing Up in Soybean

Despite the prediction of low overwintering survival we have observed bean leaf beetles in soybean this week. See our latest observations and management recommendations.

United States Environmental Protection Agency Sign plate outside the agency’s main office.

EPA Proposes a Decision to Approve Registration for Dicamba Labeling to Be Applied to Tolerant Soybean

Dicamba products previously labeled for overtop application to tolerant soybean are not registered for use during the 2025 growing season. However, the EPA has proposed to re-register these dicamba products for use in tolerant soybean starting in 2026.

Top: Green cloverworm caterpillar. Bottom: Cabbage looper caterpillar.

Green Caterpillars Causing Defoliation in Soybean

This week we observed several species of caterpillars in soybean fields. The most common species were the green cloverworm and the cabbage looper.

Corn and soybean fields with abundant weeds growing throughout.

Inexpensive and Simple Herbicide Programs in Corn and Soybean Will Not Be Effective

While selecting an inexpensive program with only one active ingredient in each application may be tempting due to the current agricultural economy, the result will likely be a more expensive problem in the future.

Dark green and tan curled caterpillars with an orange stripe along their sides.

True Armyworm Caterpillars Are Active in South Dakota Wheat

We have received a few reports of true armyworm caterpillars in wheat that are heavily feeding on the leaves. The big concern with these pests is that they will also clip wheat heads prior to harvest, so scouting is necessary to ensure that they don't cause yield losses.

U.S. Environmental Protection Agency offices in Washington, D.C.

Update on Chlorpyrifos Use in South Dakota

As of June 30, 2025, the labeled uses for chlorpyrifos products for food and feed are limited to alfalfa, soybean, and wheat in South Dakota. Chlorpyrifos can no longer be used to treat sunflowers.

Cream colored larvae on white and green soybean stem on brown dirt.

Dectes Stem Borer Adults Are Active in Soybean: 2025 Management Recommendations

Dectes stem borer adults have been collected from soybean in Southeastern South Dakota. The larvae of this pest are capable of reducing soybean yields by 10-15% due to tunneling activity in the main stem. Learn some tips for scouting and managing them this season.

Base of soybean stem with orange larvae present under the epidermis.

Soybean Gall Midge Larvae Detected in South Dakota

Soybean gall midge larvae have been detected in soybean in southeastern South Dakota. Scouting for fields with infestations may explain wilting or dying soybean along field edges.

Green waterhemp plant next to a black, ink pen. Green soybeans in the background with brown soil in the foreground.

Waterhemp is flowering. No seeds present yet.

Waterhemp is one of the most-difficult weeds to manage in South Dakota row crops. While herbicide resistance is a great factor in the difficulty of managing this weed, the biology of the species plays an important role as well.