Brown marmorated stink bug spreading across U.S.

The brown marmorated stink bug (Halyomorpha halys) has become a crop pest and household nuisance throughout Maryland and adjacent states, reports Univ. of Md. Extension. Native to Asia, the stink bug is thought to have arrived through shipping material and is now established throughout the Mid-Atlantic and parts of the West Coast. This invasive species is an excellent hitchhiker and has entered over half of the contiguous U.S.
The bugs overwinter as immature adults in houses and other structures. They are typically inactive during the winter months, but indoor heating has kept many bugs moving this year. Stink bugs re-enter the landscape in the spring where they continue to mature, mate, and lay eggs. Heightened activity usually occurs in March and April as they move outdoors.
Stink bugs consume a wide variety of plant species and feed primarily on the reproductive organs of a plant such as the fruit or seed pod. Growers have reported this pest feeding on fruit, leaves, stems, and other plant parts as well. In Maryland, the bugs have been found feeding on chrysanthemums, zinnias, sunflowers, several woody plants, tomatoes, peppers, cucumber, berries, eggplants, apples, pears, peaches, sweet corn and soybeans.

Stink bugs feed throughout the nymph and adult stages by sucking on plant material. Discoloration and dimples result at the feeding site. Reports indicate that stink bug damage alters the taste of vegetables and fruits.
USDA-APHIS is evaluating four parasitic wasps that lay eggs into the eggs of the stink bugs. The wasps (Trissolcus mitsukurrii, T. plautiae, T. flavipes and T. halyomorphae) will be evaluated in quarantine labs in Delaware over the next 2 years to ensure they don’t have an adverse impact on other beneficial bugs.

Pictured: The brown marmorated stink bug, which is now established throughout the Mid-Atlantic and parts of the West Coast, has been found feeding on some ornamental plants including chrysanthemums and zinnias.

Photo by George Hamilton, Rutgers Univ.