What Do Stink Bugs Eat?

Stink bug is the common name of insects in the family Pentatomidae. They get the name “stink bug” from the unpleasant odor they produce when they are threatened. Scientists think the bugs use the odor as a defense against predators.

There are hundreds of species of stink bugs in the United States. In the adult stage, they may be green or brown. Some are brightly colored and some have patterns on their backs. Many large adult stink bugs reach almost 2 cm in length.

In the immature, or nymph stage, the color varies from black to white. Some nymphs have white spots, which disappear as they mature. Some nymphs change color several times as they grow.

Most stink bugs are plant feeders. The first generation in the spring often feed on weeds or grasses. As they develop into adults, they often migrate into fields, orchards and residential landscapes.

In these environments, stink bugs feed on apples, peaches, berries, peppers, beans and pecans. They also feed on field crops like sorghum and cotton. Around homes, stink bugs have been found feeding on ornamental plants.

When stink bugs feed on fruits like peaches or apples, they use their mouth to pierce the skin of the fruit. The insect injects a small amount of saliva into the fruit. The saliva is toxic to the cells of the fruit, so when the damaged fruit grows, it develops a scar. The scar causes the fruit to resemble the face of a cat. Because of this, some people call stink bugs “cat-facing insects.”

Stink bugs also feed on stems and leaves of plants. Besides making fruit unfit for sale, stink bug feeding secondarily allows other insects to enter the fruit. The stink bugs can also spread plant diseases. These plant-feeding stink bugs can become serious pests in farms, orchards and gardens.

A few species of stink bugs do not feed on plants. They are predators of insects that attack plants. These predatory stink bugs have been found feeding on velvet bean caterpillars, root weevils, Colorado potato beetles and southern green stink bugs. Because of this, most gardeners consider the predatory stink bugs to be beneficial.