Brown marmorated stink bugs continue their gradual march to the south and seem to be enjoying the grain fields of northern Virginia.

Entomologists contend the southward movement is almost certain to continue.

Virginia Tech Entomologist and IPM Leader Ames Herbert says brown marmorated stink bugs, sometimes called Asian stink bugs, have reached soybean fields in northern Virginia and appear to be moving from full-season to double-crop beans.

In Maryland, veteran University of Maryland Entomologist Galen Dively says that is exactly what happened in Maryland.

Brown marmorated stink bugs thrive on tender seeds in the pods of immature soybeans. Once beans get more mature, the bugs start looking for a new food source and double-crop beans are often easy prey.

Dively, who has been working with insect pests of grain crops for better than 40 years says, “Brown marmorated stink bugs are the most dangerous pest I’ve seen.”

“In Maryland, this bug is becoming more abundant each cropping season. Populations this year are 5-10 times higher than last year,” he says. And, he adds, “we expect these stink bugs will be worse next year.”

Fellow University of Maryland Entomologist Paula Shrewsbury says apple growers in Maryland, Virginia and West Virginia have lost up to 80 percent of their crop due to damage from this pest. “Growers who have had family farms for multiple generations have told us their whole operation is in jeopardy from these stink bugs,” Shrewsbury says.

No one is exactly sure where these bugs will go next, but the best bet is more fertile grain and cotton fields to the south. Dively says heavy snowfall last winter in Maryland and northern Virginia provided a cozy environment for stink bugs and they emerged in the springtime ready and eager to feed on commercial grain crops.

The brown marmorated stink bug is a native of Asia, hence its’ common nickname Asian stink bug, and was first found in and around Allentown, Pa., in the early 2000s. It was mostly a problem for homeowners and gardeners for the first few years, but now seems destined to become a major pest of agricultural crops.

Though similar to its common cousins brown stink bugs, green stink bugs and Southern green stink bugs, the Asian version has some unique and troubling characteristics.

The native stink bugs tend to over-winter in wooded areas in and around agricultural fields. The Asian stink bugs have shown a propensity to over-winter in urban areas, specifically in very high populations in houses, sheds, barns and other structures. This trait alone has brought them notoriety in the popular press and has even captured the attention of a Pennsylvania congressman who has led a political charge to find answers to this growing pest.