- Pest Type: Insect
- Crops Affected: Wheat, Soybeans, Corn
- Scientific Name: Euschistus servus
- Pest Order: Hemiptera
The common name, stink bug, is derived from the adults' ability to emit a foul odor when disturbed. Most adult stink bugs are shield-shaped. Brown stink bugs are dull brownish-yellow in color and 0.5-0.7 inch long. The brown stink bug has white, kettle-shaped eggs. Nymphs are smaller than the adults, but similar in shape.
Both nymphs and adults have piercing-sucking mouthparts. Most damage is caused by the nymphs and adults sucking plant sap, resulting in reduced vigor, distorted leaves, and/or stunted plants. Sometimes the damage causes suckering from the base of damaged plants. They may even kill small seedlings. In corn, stink bugs may be a problem when existing vegetation infested with this pest is burned down with a herbicide and no-till corn is planted. As the new corn seedling emerge, the stink bugs may be searching for a food source. In some crops, stink bugs have also been shown to vector diseases.
Damage from stink bugs is most common where cereals are planted adjacent to rangeland, desert, pastures, etc. Most damage to cereals is caused by nymphs and adults when they feed in the head during milk or soft dough stages. The degree of damage varies, but the younger the seed when damaged, the greater the yield reduction. In addition to head/seed damage, the nymphs and adults feed on plant sap using their piercing-sucking mouthparts, resulting in reduced vigor and distorted leaves.
Stink bugs overwinter as adults and become active in the spring when temperatures rise above 70 degrees F. Each female deposits several hundred eggs, usually in June. Nymphs hatch from those eggs and pass through five instars before becoming adults. Approximately 5 weeks lapse between hatching and adult emergence. One or two generations occur per year. Populations of stink bug adults reach highest levels in September or October.
Stink bugs have natural enemies, including birds. However, the unpleasant odor which they emit repels many predators. Discuss infestation levels, thresholds, and control measures with local advisers.
Brown and green stink bugs have been reported as far north as Quebec, but are generally most injurious in the southern United States. Host plants for these stink bugs include over 52 species of crops, trees, shrubs, vines, and weeds. Preferred hosts are generally wild plants, but they move to cereals and other crops as the preferred hosts mature.