Brown Stink Bugs

We’ve already talked about brown marmorated stink bugs, consperse stink bugs, green stinkbugs, red-shouldered stink bugs, rough stinkbugs, say stink bugs, Uhler’s stink bugs, and predatory stink bugs. Today, we’re going to look at brown stinkbugs.

Brown stink bug (Katja Schultz) CC BY 2.0

Like most stink bugs, brown stink bugs (Euschistus servus) feature the classic shield-shaped body and they smell bad once threatened or stepped on. Found in Central and North America, these pests damage a wide variety of garden plants including alfalfa, beans, buckwheat, corn, millet, okra, peas, pecans, sorghum, soybeans, sunflowers, and walnuts, along with several fruit trees.

Brown stink bug description

From above, brown stink bugs have a mottled gray to brown back, pointy shoulders, and rust-colored legs with tiny black dots. If you were to flip one over you would see that the underbelly is yellowish, with an orangish area in the middle of the belly. Adults average ½” in length. 

Front view of brown stink bug (xpda) CC BY-SA 4.0

Eggs are clusters of yellowish-white spheres that start turning pink before they hatch. Nymphs are tiny reddish-brown ladybug-shaped insects.

Brown stink bug nymphs and eggs (Judy Gallagher) CC BY 2.0

Brown stink bug damage

Brown stink bugs move through the garden as the seasons change. They love to start with peaches and nectarines, causing catfacing and other types of fruit scarring. From there, they move to whatever is nearby and edible. They feed by inserting needle-like mouthparts into fruits, leaves, stems, and seed pods. When they do so, they inject toxic substances into the plant that may slow or halt the further development of that plant part. Over time, the accumulated effects of brown stink bug feeding can be pretty devastating to a crop. They can kill seedlings outright, cause stunting of larger plants, and provide points of entry for several pathogens.

Brown stink bug lifecycle

Adult brown stink bugs overwinter in dead weeds, under boards, in hedgerows, and in the bark of trees. As soon as temperatures start rising they emerge to start eating, breeding, and reproducing. Each female lays an average of 18 egg masses. Each mass contains 60 eggs or so. There can be as many as four or five generations a year, depending on the weather. Adults are strong flyers so you have to keep a lookout.

Brown stink bug management

Assassin bugs, green lacewing larvae, some parasitic wasps, and earwigs are also known to feed on stink bugs, so you’ll want to avoid using broad-spectrum insecticides. In fact, most stink bugs are resistant to insecticides and pesticides. Row covers can also be used to protect specific plants and crops against stink bug damage. Your best defense against brown stink bugs is to monitor plants regularly, handpick stink bugs when you see them, and squash any egg or nymph clusters you see.