Stink bugs, sometimes referred to as shield bugs, are members of the Hemiptera order. These bugs are aptly named because they have small glands located on the thorax that are capable of emitting a bad smelling liquid. This ability is believed to be a defense mechanism that can be employed against predators; when a stink bug is mishandled, for example, it will release a foul odor.
There are thousands of species of stink bugs throughout the world. Two of the most well-known species are the brown stink bug (Euschistus servus) and the green stink bug (Acrosternum hilare or Chinavia hilaris). Both are commonly found throughout the US and other countries, particularly in Asia, where many species are thought to have originated.
Stink bugs range in color from brown to brilliant green, although many are duller shades designed to blend in with vegetation; a few, however, have bright orange markings that are thought to serve as a warning to predators. Nearly all species are distinguished by a triangle- or shield-shaped plate on their backs. Stink bugs are part of an order of insects sometimes called "true bugs," which do not chew with their mouths; instead, they have a proboscis that allows them to suck the liquids out of vegetation or other creatures.
Many species of stink bugs reproduce rapidly, with some laying eggs several times a year. Females typically lay multiple batches of eggs, often on plant leaves, which hatch in about a week; it typically takes several additional weeks for the insects to mature from nymphs into adults. The nymphs closely resemble adults, although adults have four wings and the nymphs none.
These bugs generally are active from spring to late fall in most regions. At night, they are attracted to light and therefore can sometimes be seen flying around. Often, they hang around different types of vegetation, especially tomatoes, melons, and beans.
Most stink bugs are plant eaters, making them serious pests to agriculture and home gardeners alike. In significant numbers, these species can be very damaging to crops, particularly peaches, soybeans, cotton, and grains. Certain species can damage stalks so that a plant cannot produce grain, or even kill seedlings. When they feed on peaches and tomatoes, they can create ugly scars and malformations called "catfacing."
A few species of stink bugs are considered helpful rather than harmful to plants. The anchor bug (Stiretrus anchorago) and the rough stink bug (Brochymena arborea), for example, prey on caterpillars, beetles, and other pests. Before assuming that a stink bug is harmful, a gardener may want to try to identify it.
Stink bugs can be difficult to control because they are resistant to some insecticides; there are a few varieties that do work, however, and they can be tried if the bugs become a problem. If they are found in a garden, cleaning the area thoroughly, including pulling up and removing weeds, disposing of all leaf litter and other waste, and washing pots and other garden items, can help reduce their numbers. Using a power washer to clean the outside of a house and any other outdoor structures may also help.
Homeowners should keep doors and windows well sealed to help prevent the bugs from getting in, as they often seek shelter inside houses during the winter. If stink bugs are found inside a home, they can be vacuumed up or gently picked up by hand and disposed of quickly. People should be cautious while handling stink bugs; they are not harmful to humans, but they will release their odor when handled roughly. The unpleasant smell tends to linger, but unlike the similar odor of a skunk, the scent can be washed away by using soap and water.
Stink Bugs as Food
Stink bugs are eaten in some parts of the world, and people who eat them often say that the bugs' strong odor enhances their flavor. In Laos, they are sometimes eaten fried or mixed into a paste along with spices and herbs. They are sometimes eaten live in Mexico or are mixed into salsa or used as part of the filling for tacos.