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Soybean Insects

All Soybean Insects Content

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

Dectes Stem Borer Adults Detected in South Dakota Soybean

Dectes stem borer adults have been collected from soybean in Southeastern South Dakota this week. As a reminder, the larvae of insect pest are capable of reducing soybean yields from 0-17% due to its feeding activity inside of the main stem.

soybean pods

Soybean

SDSU Extension is your partner to increase yields and improve efficiency.

aerial view of South Dakota farm and surrounding land

Crops

During the growing season, SDSU Extension provides weekly production recommendations.

Aerial view of test plots at the Volga Research Farm.
Jul 29

Integrated Pest Management (IPM) Field School

SDSU Extension will host an IPM Field School at the SDSU Volga Research Farm (21200-, 21298 464th Ave., Volga, SD 57071) on Wednesday, July 29, from 9:00 a.m. - 4:00 p.m.

Numerous nymph grasshoppers feeding on corn.

Large Grasshopper Nymph Populations Detected in Southeast South Dakota

This week we received several reports of large grasshopper populations originating from southeast South Dakota. The populations were well above threshold and actively defoliating crops.

Small shiny fly larvae with black heads on a brown plant root.

Fungus Gnats Affecting Soybean Emergence

We have recently received a report of a maggot attacking soybean seedlings. During most years, we would immediately expect this to be a case of seedcorn maggots, but it was fungus gnat larvae.

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 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.