Brown marmorated stink bug seen inside the house | Characteristics
What’s flying around the house? It’s winter, so what is it and how did it get into my house?
The large brown insect is the brown marmorated stink bug. Usually, stink bugs are not accidental invaders, but the BMSB is attracted to homes and structures as a protected overwintering site.
The number of these insects found in homes is increasing compared to last year. Two challenges with this pest are keeping them out of homes and reducing the food damage they cause on a wide range of crops.
The brown marmorated stink bug was first discovered in the United States in 1998 in Allentown, Pennsylvania. It was first reported in Kentucky in 2010 and in Daviess County in 2013. Because this stink bug aggregates, food damage on fruits and vegetables is worse than damage caused by native bug species.
Daviess County’s population is growing, especially with the experience more inside the home this winter, with the expectation of more damage to fruits, vegetables and crops and an increase in large numbers of them se gathering on houses to find a wintering site in the fall.
This bug does not bite humans or pets. They do not reproduce or reproduce indoors. Remove bedbugs found in the house, alive or dead, with a vacuum cleaner.
When disturbed, they produce a foul odor, so the vacuum will smell for some time. To limit odors and save bags, place a cut-out nylon stocking in the suction tube of the vacuum cleaner.
It is not recommended to use an insecticide indoors to manage them. If large numbers are found in wall voids or attics, killing them may eventually lead to the beetles feeding on the dead bugs, leading to attacks on woolens, stored dry goods, or other natural products. It is not recommended to treat the cracks and crevices where bedbugs can emerge with an insecticide as this will not stop them.
Keeping them out of the house or structure is the best management. Cracks as small as 0.125 inch allow some insects to get inside. Use quality silicone, silicone-latex caulk, or an appropriate sealant to close cracks around windows, doors, siding, utility pipes, behind chimneys, under wood fascia, and any other openings. Also install a screen 0.17 inch or less behind the attic vents.
This can be done throughout spring and summer in anticipation of insects seeking overwintering sites in September.
How do you identify a marmorated stink bug? They have piercing mouthparts and suck nutrients from plants. A brown marmorated stink bug can be recognized as a relatively large, flattened, shield-backed stink bug with five segmented antennae. It measures approximately 0.625 inches long. Its name comes from the mottled colors of brown and gray on its back.
The underside is variable in color but is much lighter than the top. It has two broad, light-colored banded areas on the antennae, which sets it apart from other similar bugs. The brown marmorated stink bug’s abdomen extends beyond the wings, resulting in light-colored “triangles” visible beyond the edges of the wings. When disturbed, the insect leaves a smell of coriander.
The brown marmorated stink bug could be confused with other brown stink bugs common throughout the state and found on many of the same fruit, vegetable, and field crops. We have at least three pest species of brown stink bugs in Kentucky.
Two of the largest species of brown stink bugs may have the last one and a half segments of the antennae darkened. However, they do not have light-colored bands on the antennae.
Brown stink bugs have a series of fine teeth on the leading edges of the thorax. They do not attempt to enter homes in large numbers.
Like other stink bug species, BMSB nymphs and adults use their biting-sucking mouthparts to feed on plant leaves and fruit.
Their feeding results in small discolored or necrotic areas on the leaves. Fruit damage includes mild to severe water-soaked legions or cat-faces. This bug feeds on more than 100 plant species and is very mobile.
Bedbug populations begin to build in May. To manage them in the garden, covering the plants with fine netting of 1/6 inch or less blocks the pest.
However, nets may not be practical with crops that need pollinators to produce fruit. When pest populations are low, routine hand picking in the morning when slow and dropping them into a bucket of soapy water can work for a small number of plants.
In the vegetable garden, the last resort is chemical control. Remember that the product must be labeled for use on the specific crop. Check days to harvest after product application and protect pollinators by applying product in the evening after zucchini and cucumber flowers close or avoid application while plant is in bloom .
Through scientific studies, some of the pyrethroid insecticides containing the following active ingredients have been shown to be effective: bifenthrin, zeta-cypermethrin and cyfluthrin. Malathion, which is an organophosphate, may also be effective.
For more information on the brown marmorated stink bug, contact the Daviess County Cooperative Extension Service at 270-685-8480 or [email protected]
If you are having trouble identifying the brown marmorated stink bug, take it to the Daviess County Cooperative Extension Service office for assistance. Home pest control is the best way to keep them out.
Annette Meyer Heisdorffer is the Daviess County Horticulture Extension Officer. Her column airs weekly on Lifestyle’s Home & Garden page. Email him at [email protected]