What Are Stink Bugs?

Stink bugs are large, oval or shield-shaped insects. They are members of the insect order Hemiptera and the family Pentatomidae. They get their common name from the odor of the chemical that they produce in glands on their abdomen. Scientists suspect this odor might be a defense against predators.

Depending on the species, adults can reach almost 2 cm in length. Their bodies are almost as wide as they are long. Adult stink bugs can fly fairly well. They keep their wings folded over their backs when they land. Their long legs extend from the sides of their body.

As adult insects, a few species of stink bugs are brightly colored. The most common ones are green or brownish. The immature stink bugs are called nymphs. They can range in color from black to yellowish. Many nymphs change color several times as they grow. Some stink bug nymphs have spots or other distinctive markings. The nymphs of the brown marmorated sting bug have red eyes.

Many species of stink bugs feed on plants. Some stink bugs become serious pests of crops. When they attack fruits, like peaches, they make the fruit unfit for sale.

A few species of stink bug are predators of other insects. These predatory stink bugs can actually help protect crops against destructive pests. They eat caterpillars, beetles and even plant-feeding stink bugs.

Stink bugs can become household pests when they invade homes for warmth. They enter homes in the late summer or fall. They get into the home through cracks or holes in screens. They remain hidden through the winter and become active in the spring. As the stink bugs move around to find an exit, they often come out into the living space of the home. The bugs cluster on the walls or inside of windows.

Homeowners can prevent stink bug invasions by making an inspection of their homes and sealing cracks and openings. Vents in the attic and in the crawl space are common entry points, so these should be checked very carefully. Missing or torn screens should be repaired.

Cracks around doors and windows can be sealed with caulking. Gaps under exterior doors can be sealed with weather stripping.