COLUMBUS, Ohio – The annoying stink bug is no stranger to any homeowner. Anyone who has had an encounter with these ugly pests are too familiar with their pungent spray and home invasion.

What most are not aware of is this pest’s threat to agriculture. They’re known to eat at least 100 types of crops and it’s estimated that these stink bugs cost millions of dollars in damages to corn and soybeans across the Midwest. The stink bug has caused roughly $37 million in damages to mid-Atlantic apple crops alone.

The brown marmorated stink bug (BMSB) was accidentally introduced into the United States from its native range in Japan, Korea and China. The first specimen of this pest was collected in 1998 in Allentown, Pa. By 2020, it had spread to 46 states as well as four Canadian provinces. It was first documented in Ohio in 2007, in Franklin County. Since then, it has been documented in 62 of Ohio’s 88 counties.

The stinky bug made its way to Indiana (Elkhart County) in October 2010 and is now distributed statewide. It was first detected in Iowa and Illinois in 2011.

Homeowners know them as a nuisance that invades homes and garages in the fall. Ask any grower in the Farm World readership area and they’ll tell you they’re invading their corn and soybeans.

The BMSB are the most common stink bugs attacking corn in these regions. These insects are ½-inch long, shield shaped and have piercing-sucking mouthparts. The upper side of the body ranges from light to very dark brown. The underside varies from light yellow to green.

According to Celeste Welty and Kelley Tilmon, entomologists at The Ohio State University, stink bugs feed on a wide variety of cultivated crops and weeds. Soybeans are a favorite late summer host, and the dramatic growth in soybean acreage during the recent years has contributed to steadily increasing numbers of these insects. This increase coupled with certain cultural practices and crop rotation, can lead to stink bug damage to early growth stages of corn.

Stink buys feed on plant fluids by inserting their needlelike mouthparts into stems, leaves or seed pods. While feeding, they inject materials into the plant to aid in digestion and sap removal.

Penetration by the mouthparts can cause physical damage, much like stabbing the plant with a fine needle. A combination of mechanical and chemical damage to the growing point of the plant may be responsible for the injury and symptoms seen in the field.

“Stink bug feeding causes three types of damage. They may kill small seedlings, produce stunted plants, or cause ‘suckering’, the production of tillers from the base of the damaged plants,” Welty said. “Frequently a series of plants along a row may exhibit a progression of these symptoms, giving a stair step appearance.”

Surveys in Kentucky and adjacent states have identified a soybean-wheat-corn sequence as especially favorable for stink bug damage. A stink bug population can build up in soybeans during podfill. Wheat cover crops provide an attractive early spring host for the insects, and subsequently they feed on emerging corn. The stink bugs may overwinter in the wheat stubble, or they may leave the field for over wintering sites and return in the spring.

Stink bugs also enjoy all sorts of fruit crops, such as peaches, apples, pears, Asian pears, cherry, grapes, raspberries, blackberries and blue berries. They can be a terror to sweet corn, peppers, tomatoes, eggplant, okra, green beans, peas, Swiss chard, sorghum and sunflowers.

Tree enthusiasts have to be concerned as well. Stink bugs can damage catalpa, redbud, Japanese tree lilac, crabapple, mulberry, black cherry and maples.

Crops that are at low risk for damage by this pest are cucurbits (cucumbers, squash, pumpkin) and cole crops (broccoli, cauliflower, cabbage), onions and potatoes.

Tilmon has been working with the Ohio Soybean Council and soybean checkoff to develop easier BMSB scouting methods for soybean farmers. She’s analyzing the effectiveness of pheromone-coated sticky cards places around soybean fields. The cards were originally developed for orchard crops, but Tilmon believes they will provide a quick and easy way for soybean growers to determine if they have a BMSB problem or not.

The BMSB overwinters in the adult state in houses, barns, sheds and other protected places. The adults begin to fly to these overwintering sites in the middle of September, and peak flight activity is in late September or early October. Adults emerge from their overwintering sites in the spring, usually in early May. After they feed for about two weeks, they mate, and the females begin to lay eggs in clusters. A single female can lay up to 400 eggs. Eggs hatch in three to seven days. New adults start to appear in late July or August.

Without natural predators, diseases and other pressures from their native environments to keep them in check, the stink bug populations can explode to catastrophic numbers.