Skip to main content

Content by Philip Rozeboom

Sunflower moth, banded sunflower moth, and sunflower maggot adult.

Sunflower Pest Recap

During 2026, we will be producing a new weekly update on sunflower insect pest activity. This information will be attained via a sampling network of eight locations that are in central South Dakota.

: Two photos with various plants that are brown, yellow, and/or green. A blue pen is in the foreground of each photo for size reference.

Clock tells the time of the day, not when the job is done. Is that true for weed management?

Common banter at the farm gate implies farmers work long days to get the job finished. However, weed management may improve if spraying stops at a particular time of day.

Small shiny black beetle with two light tan stripes on elytra.

Alfalfa Should Be Scouted for Presence of the Palestriped Flea Beetle

Palestriped flea beetles have recently been observed in alfalfa fields in South Dakota. Large populations of palestriped flea beetles can cause rapid defoliation and stunt seedling alfalfa.

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

Soybean Gall Midge Larvae Active in South Dakota

Soybean gall midge larvae are active in soybean in southeastern South Dakota. The first symptoms of an infestation during this part of the season vary based on the size of the population within the plant.

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, a Vector of Bean Pod Mottle Virus, May Be Active in Soybean

Although we are predicting low overwintering survival of bean leaf beetles this year in South Dakota, scouting for this pest should still be conducted, as every year we still observe populations in soybean.

Soybean plants cut by cutworm caterpillars

Keep an Eye Out for Cut Soybean Plants: A Sign of Dingy Cutworm Presence

Dingy cutworms have been observed in South Dakota no-till soybean fields. Their activity will likely continue for at least another couple of weeks.

Green wheat with small mites present near the tips of the leaves.

Drought Stress in Wheat Leads to Increased Banks Grass Mite Activity

There have been reports of large populations of Banks grass mites in South Dakota wheat fields. Banks grass mite populations are more successful during hot, dry weather that also increases the susceptibility of wheat due to it being drought stressed.

Green leaf infested by small insects that are brown and black.

Early Season Soybean Infested by False Chinch Bug

At the end of last week, we received several reports of false chinch bugs attacking seedling to early vegetative stage soybean in South Dakota. In these cases very large populations were present on seedling soybeans as well as the ground around them.

Redlegged, differential, and twostriped grasshopper nymphs.

Various Grasshopper Species Are Active Across South Dakota

While scouting, we have noticed increased grasshopper nymph activity and in some areas these populations are close to threshold levels. Crops in areas that have had high populations should be regularly scouted to ensure that extensive defoliation doesn’t go unnoticed.

A red, weed hoe next to a freshly cut, green weed surrounded by brown soil.

Reminder: Cutoff for over-the-top dicamba products labeled for soybean is June 30 or R1 growth stage in South Dakota

Over-the-top dicamba products for application in soybean have been relabeled for the 2026 growing season. A stipulation for applying these herbicides is a cutoff date of June 30 or R1 soybean.