By now most people are familiar with the Asian lady beetle, an introduced pest that invades homes as cool weather approaches. They are at least beneficial in that they feed on aphids, a common plant pest. Now homeowners in North Carolina are faced with two new exotic insect species from Asia, kudzu bugs and brown marmorated stink bugs, that are also invading homes with the cooling temperatures.
In the Piedmont, most people are currently reporting problems with the brown marmorated stink bug (BMSB). They should not be confused with our many native stink bug species, which do not commonly invade homes. The BMSB was first reported in Pennsylvania in the late nineties. They were here in small numbers in 2011 and went mostly unnoticed. Now that the population has become established, many people are reporting them in high numbers.
The adult BMSB has the typical shield shape, is dark mottled brown, and are over half an inch long. They can be distinguished from our native species by the alternating light and dark bands on the antennae and light and dark banding on the edges of the abdomen. Aside from invading homes, they feed on many ornamental plants, fruit trees, and vegetables.
The kudzu bug was first reported in Georgia in 2009 and has spread to several southeastern states. The adults grow up to one-quarter inch, are somewhat oblong in shape, and are olive-green colored with brown speckles. They are “true bugs”, like stink bugs, and have piercing sucking mouthparts. Yes, they feed on kudzu, but they also feed on other legume species, such as soybeans, causing significant impacts to crop yields.
As with other nuisance pests that invade homes, prevention is key. It is not practical for homeowners to treat indoors or inside of homes with pesticides to control these pests. They can fly and go anywhere in the home, and they are still moving in and will be for weeks, which would require multiple pesticide applications. Foggers do provide a large coverage area, but they only kill bugs that are present at the time of applications, so again multiple applications would be necessary. When using any pesticide always thoroughly read and follow the label. Fatal accidents have occurred in homes with foggers that are misapplied.
Since these pests are here to stay, long-term control measures should be taken. This means sealing up any possible entry points. Check weather stripping and replace as needed around doors and windows. Check for cracks or gaps in siding, around windows or doors, outlets, air conditioner units, and other places on the exterior of homes, and seal with caulk or expanding foam. Check screens and replace, as needed, using window grade screening, especially around attic entry points. Pesticides can be used outside the home or structure targeting critical entry points, but this only provides a temporary solution and may not prove to be very effective. There are stink bug traps available for the BMSB, but no effective, commercial traps appear to be available for kudzu bugs at this time. Again, mechanical exclusion is the best long-term solution.
Once the insects make it into the home, they can be captured and removed. The top can be cut off of a plastic bottle and inverted into the bottle to make a simple funnel to catch the invaders. If they are present in large numbers a vacuum works well, but should be immediately emptied, because both insects will leave an odor in the vacuum. To kill the insects, they can be sealed in a plastic bag and frozen in the freezer or dumped into a bucket of soapy water. Once dead, discard them outside.
For more information or questions, contact North Carolina Cooperative Extension, Yadkin County Center, at 336-679-2061.