Defoliators and Pod Feeders are Now Present In Soybeans

There are a number of different insects that may be present in soybeans right now. The usual collection of bean leaf beetles, Japanese beetles, grasshoppers, stink bugs and aphids joined by green cloverworms, podworms (corn earworm), alfalfa caterpillar, thistle caterpillars, lygus bugs and loopers. Throw in a few spider mites and the potential for yield loss can be dramatic. The population of many of these insects and mites will be sporadic from field to field and therefore require proper scouting. Pay particular attention to scouting for spider mites in areas where conditions have turned dry as the potential for mites will be greater.

An additional concern in 2010 is the occurrence of two new stink bugs common in the south making their presence known further north into Missouri, Illinois, Kentucky and Indiana. The new stink bugs are the red-banded stink bug and the red shouldered stink bug. The adults are similar in appearance to the green stink bug but with noticeable reddish markings across the top of the wing covers for both species and around the perimeter of the body for the red-banded stink bug. The key identifier between the species is a spine at the third pair of legs which points toward the head for the red-banded stink bug. In tests where the red-banded stink bug was caged on soybean plants for 72 hours 41 percent of the seeds were damaged and seed weight was reduced by a third.

Soybeans are currently in the pod fill stage of development which is critical to maximizing the yield capability of the crop. Insect and mite damage from a complex of several pests feeding in the crop can reduce the productivity of the plants by damaging foliage and introducing toxins into the plant. Even greater loss is caused by the insects that feed directly on the pods and seeds developing in the pod. In addition to the feeding damage the wounds created also open the pods to the introduction of diseases which further reduce the value of the seed.

Photo ID of Common Soybean Pests

		Japanese beetle - pest of corn and soybeans, skeletonizes the leaves of the soybean plant.
		Bean leaf beetle - black triangle at top of wing covers, four primary spots visible from top, color varies from tan to red. Feed on the leaves creating rounded holes and on the pods.
		Bean leaf beetle pod feeding - feeding does not go through to the seed.
		Green cloverworm - white stripe down side and light green body. Feed on the leaves.
		Alfalfa caterpillar - white stripe down the side and darker velvety green body with no spines. Feed on the leaves.
		Corn earworm - distinct spines and stripes, feed on soybean pods.
		Thistle caterpillar - multi-branched spines, leaves webbed together.
		Grasshoppers - several species, feeds on foliage and pods.
		Green stink bug - shield shaped. Feeds by puncturing through pod into the inner bean.
		Red banded stink bug - very noticeable spine between the third pair of legs which points toward the head. Feeds on leaves and pods similar to green stink bug.
		Tarnished plant bug (Lygus species) - piercing sucking mouth parts remove plant fluids from the foliage while introducing toxins.
		Two-spotted spider mite - Eight legs, two dark spots on body, webbing on underside of leaves. Feed on leaves drawing critical fluids from the plant cells.

FMC Products for control: Mustang Max Insecticide is labeled for the control of these insects and Hero Insecticide is labeled for the soybean insect complex as well as spider mites. Rates may vary depending on the particular insects or spider mites present on the crop. Consult the label for use recommendations.