extension.ca.uky.edu HORTICULTURE Annette Meyer Heisdorffer, PhD Daviess County Extension Office September 3, 2017 Preparing for Accidental Insect Invaders Pest proofing your home is the best way to keep insects out. In the fall, insects look for locations to overwinter. Dr. Lee Townsend, University of Kentucky Cooperative Extension Entomologist, reminds us that several insects become accidental invaders into the home. The brown marmorated stink bug and box elder bug may be insects trying to come inside this fall. An insect pest that may be seen on sides of buildings on warm fall days is the brown marmorated stink bug. This is a relatively new insect pest to the area. During the summer months it can be a very serious pest of many fruit, vegetable, nursery, and field crops. It was found for the first time in Daviess County in 2013 inside a home. As it moves to a new area, it is first noticed as a mass of insects on the outside of buildings. Then during the growing season, damage due to this stink bug may be seen in field crops and garden plants. Stink bugs are roundish, shield-backed bugs with five segmented antennae. The rown marmorated stink bug can be recognized as a relatively large and flattened stink bug. It gets its name from the marbled brown and gray colors on its back. The underside is variable in color but is much lighter than the upper side. To distinguish it from other similar stink bugs, such as the brown stink bug, it has two wide, white, banded areas on the antennae. A hand lens can be used to see the bands. The abdomen on the brown marmorated stink bug extends past the wings
exposing light colored triangles past the wing edges. It also has only one small tooth along each leading edge of the thorax; this tooth is just behind the eye. When disturbed, it will leave a cilantro-like odor. Mechanical exclusion is the best method to keep stink bugs from entering. Cracks around windows, doors, siding, utility pipes, behind chimneys, and underneath the wood fascia and other openings should be sealed with good quality silicone or silicone-latex caulk. Damaged screens on doors and windows should be repaired or replaced. Boxelder bugs are common insects that feed on sap from leaves, twigs, and seeds of boxelders as well as other members of the maple family. Large numbers of them accumulate in the fall and can be seen on tree trunks or branches, or sunning themselves on the south or west sides of buildings. Adult boxelder bugs are elongate, one-half inch long insects with sucking mouthparts. They are mostly black with some red markings. There are three narrow red lines on the segment behind the head, one down the center, one on each side, and a thin red inverted "V" about the middle of the back. The wingless immature or nymphal stage has a black head, antennae, and legs. The red abdomen has an orange-yellow stripe and spot down the center of the back. Boxelder bugs feed on plants during the summer. They move to sheltered areas including nearby houses and buildings in the fall and remain there during the winter. Sweep or vacuum and discard those found inside. They will not multiply nor will they infest any household articles. These harmless insects are only a nuisance or accidental invader; however, they may leave an odor and stain when crushed.
Exclusion is important in reducing numbers that get indoors. Check door sweeps and places outside the house that may allow them to get inside. Insecticidal soap can be sprayed directly on the boxelder bugs congregated on outside walls as a safe means of control. Exterior applications of insecticides may offer some minor relief from infestations where the task of completely sealing the exterior is difficult or impossible. Homeowner products containing the active ingredients deltamethrin, cyfluthrin, lambda-cyhalothrin, cypermethrin, or permethrin are options. They should be applied in the fall as the bugs begin to congregate. These insecticides are broken down by sunlight so the residual effect will decrease and may not kill the insects much beyond several days or a week. If numerous bugs are entering the living areas of the home, locate the openings where the insects gain access. Typically, stink bugs will emerge from cracks under or behind baseboards, around window and door trim, and around exhaust fans or lights in ceilings. Seal these openings with caulk or other suitable materials to prevent the insects from crawling out. Both live and dead stink bugs can be removed from interior areas with the aid of a vacuum cleaner; however, the vacuum may acquire the smell of stink bugs for a period of time. nor will they infest any household articles. These harmless insects are only a nuisance or accidental invader; however, they may leave an odor and stain when crushed. Exclusion is important in reducing numbers that get indoors. Check door sweeps and places outside the house that may allow them to get inside. Insecticidal soap can be sprayed directly on the boxelder bugs congregated on outside walls as a safe means of control. Exterior applications of insecticides may offer some minor relief from infestations where the task of completely sealing the exterior is difficult or impossible. Homeowner products
containing the active ingredients deltamethrin, cyfluthrin, lambda-cyhalothrin, cypermethrin, or permethrin are options. They should be applied in the fall as the bugs begin to congregate. These insecticides are broken down by sunlight so the residual effect will decrease and may not kill the insects much beyond several days or a week. If numerous bugs are entering the living areas of the home, locate the openings where the insects gain access. Typically, stink bugs will emerge from cracks under or behind baseboards, around window and door trim, and around exhaust fans or lights in ceilings. Seal these openings with caulk or other suitable materials to prevent the insects from crawling out. Both live and dead stink bugs can be removed from interior areas with the aid of a vacuum cleaner; however, the vacuum may acquire the smell of stink bugs for a period of time. It is not advisable to use an insecticide inside after the insects have gained access to the wall voids or attic areas, because there is the possibility that carpet beetles will feed on the dead stink bugs and subsequently attack woolens, stored dry goods, or other natural products in the home. For more information on insect pest proofing your home, contact the Daviess County Cooperative Extension Service at 270-685-8480. More information about the brown marmorated stink bug can be found at http://pest.ca.uky.edu/ext/bmsb/welcome.html. Annette s Tip of the Week: The Asian lady beetle, with the black M behind the head, is looking for overwintering sites too. They are not harmful, but will emit a disagreeable odor and produce a yellowish secretion which stains when disturbed. The same control measures should be followed as for the boxelder bug listed above.
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