Eggs and newly hatched nymphs;
Photo by David R. Lance,
Nymph; Photo by David R. Lance,
Adult; Photo by David R. Lance,

Brown Marmorated Stink Bug (BMSB), Halyomorpha halys, is an exotic pest native to Asia. It was first introduced to the United States in 1996 in Pennsylvania. It has since been reported in 40 states including all states east of the Mississippi River, Oregon, California, Minnesota, Texas, New Mexico, Arizona, Nebraska, and Iowa. It has been intercepted in North Dakota, but so far has not been reported to cause damage or as a nuisance pest. This pest easily hitch-hikes around so spread is inevitable. BMSB is very mobile and can quickly switch hosts. They will move from early-ripening crops to later maturing ones. Almost any plant could be at risk.

BMSB has a wide host range in North America. Of particular interest to our region are apple, crabapple, cherry, currant, maple, linden, serviceberry, honeysuckle and rose. It can affect garden crops including peppers, tomatoes, blueberries, raspberries, grapes and probably many more. It is also a pest of agronomic crops such as soybean and corn. BMSB can also be a indoor pest in the late fall, much like the boxelder bug. They congregate in large numbers in homes looking for a warm place to overwinter.

Description – BMSB like other stink bugs are a “true bug” and therefore have the typical shield-shape. They are approximately 5/8th inch long and 3/8th inch wide. The top-side of their body is mottled shades of brown and grey. The underside of the body is white or light grey. They also have dark blue or copper puncture marks on their heads and dark red eyes. The BMSB can be distinguished from other stink bugs by the alternating light and dark bands on their antennae.
Damage – Stink bugs feed by sucking plant juices with their straw-like mouthparts. On leaves, this feeding will appear as light colored stippling that can turn necrotic over time. On fruit, the feeding causes a distortion that is referred to as “cat-facing” and makes the fruit unusable as a fresh product. In bean the damage usually occurs on the immature beans and pods.

Report any suspect insects to: 
The North Dakota Department of Agriculture
 at 701-328-4765 or 701-239-7295

NDSU Extension at 701-231-7908

Additional Information