The kudzu bug is a small insect, 1/8 to 1/4 inch long at full size—roughly the same size as a ladybug. Its body is oblong, with olive green coloring and brown speckles. When crushed, the bugs can stain surfaces and cause a foul odor. The kudzu bug is also a notable agricultural pest, feeding on soybeans and other legumes. It emits a foul-smelling odor as a defense mechanism, which is why it’s often confused with the brown marmorated stink bug (Halyomorpha halys), another invasive insect that’s native to different parts of Asia.
Kudzu bugs are most noticeable at two times of the year: early spring when they emerge from winter hibernation and fall when they congregate on sunny spots to warm themselves. They are attracted to light-colored surfaces, especially white house siding, white cars, and even white shirts. During their winter inactivity period, you might see groups of them in cracks of house siding, spaces around windows, or even in crevices of trees. Kudzu bugs are often considered nuisance pests, similar to boxelder bugs or ladybugs.
4 Ways to Get Rid of Kudzu Bugs
If kudzu bugs do get inside your home, they should be vacuumed up with a hose attachment and disposed of while still in the vacuum bag. The bag can be submerged in hot, soapy water or placed in a freezer to kill the bugs. Avoid crushing them, as they can stain surfaces and leave an unpleasant smell.
Spray the Adult Insects
A variety of household spray pesticides will kill kudzu bugs, but these products can be hard to use since the bugs often congregate high on exterior walls. If you do spray for the bugs, use a pyrethrin-based pesticide, such as permethrin, bifenthrin, or lambda-cyhalothrin (chemicals that end in "-thrin" are pyrethrin-based products).
When using these products outdoors, be careful about allowing the pesticide to drift in the wind, and take care when spraying overhead not to allow the pesticide to drip into your eyes or onto your skin. When using pyrethrin-based products, be careful not to use them in a manner that allows for run-off into storm drains. These chemicals are toxic to fish and other aquatic life, though relatively safe for humans and other animals.
When using a pesticide outdoors, make sure the product is approved for outdoor use. Some types are restricted to indoor use or have special handling instructions when they are used outdoors. Some products carry specific warnings against broadcast application.
Spray the Nymphs
While spraying for adult insects normally takes place in the fall when the adults are seeking hiding places for the coming winter, some evidence suggests that it is more effective to spray the vulnerable plants earlier in the year to target the just-hatched nymphs as they feed. This method is more often used in commercial agriculture to protect soybeans and other crops, but homeowners may also find it effective to use bifenthrin to spray vulnerable plants, such as wisteria and green beans, just as the nymphs are hatching.
The nymphs are tiny, fuzzy-looking insects, yellow in color, that cluster on leaves and stems. Thorough spraying of vulnerable plants as each generation of nymphs is emerging often reduces the later adult populations that can invade homes. Homeowner spraying is not very effective, though, unless nearby commercial soybean fields are similarly treated.
Call an Exterminator
A professional exterminator may be the best option if you have trouble controlling the bugs yourself. Professionals will have the tools and pesticides necessary to spray your home's exterior all the way to the roofline. Be aware, though, that several weekly treatments may be necessary to fully control the bugs when they are active in the fall.
What Causes Kudzu Bugs?
Kudzu bugs are more likely to be found in regions where their favorite foods are available: kudzu vine and various legume plants. Regions where soybeans are grown commercially are especially vulnerable to kudzu bugs.
How to Prevent Kudzu Bugs
Kudzu bugs are likely to congregate wherever they find food sources. Eliminating invasive kudzu vine from nearby areas may help reduce populations of kudzu bugs. The insects also like to feed on wisteria vine, as well as legumes such as peas and beans. Avoiding these plants in your landscape may help reduce local populations.
To prevent the bugs from getting indoors, carefully seal all gaps in the exterior of your home, around windows and doors, around vents and pipe openings, and at the foundation. Painting your home a darker color may also help, as the bugs seem to be drawn to lighter colors.
Frequently Asked Questions
Where Is the Kudzu Bug Found?
Although native to India and China, the kudzu bug (Megacopta cribraria) has become a pest in the southeastern United States, particularly Tennessee, Florida, Alabama, Virginia, North Carolina, and South Carolina. Also known as the bean plataspid, lablab bug, and globular stink bug, it was first discovered in the U.S. in 2009 in Georgia. Just a couple of years later, it was seen in neighboring states, and scientists believe it will continue to spread.
What Kind of Damage Do Kudzu Bugs Cause?
Kudzu bugs are named after the plant they prefer to feed on: kudzu. Kudzu is native to different parts of Asia but is a common sight in the Southeastern U.S., where it's considered an invasive vine.
The bugs also commonly eat soybean plants, which can dramatically impact crop production. They suck the juices from the plants, causing the leaves to dry out and the plants to wither and die due to the lost nutrition. Kudzu bugs also feed on other types of legume plants, which can impact both farmers and home gardeners. Many flowering plants are also members of the legume group; wisteria, for example, is one of the ornamental plants often subject to kudzu bug infestation.
Similar to stink bugs, boxelder bugs, and squash bugs, the kudzu bug can become a very annoying home pest. When given the opportunity, these bugs will move indoors through ill-fitting screens, cracks, and other openings to seek warmth in the winter. And controlling them can be frustrating because of their odor and staining capabilities. If they’re crushed on furniture, carpeting, or another surface in your home, not only can the stain be difficult to get out, but the odor also can linger.
What Is the Life Cycle of This Pest?
The lifecycle of the kudzu bug depends on regional temperatures. On average, it takes about six weeks for eggs to hatch and develop into adults. In most regions, there are two generations per year. The second generation seems to have a preference for legume (bean-related) plants, while the first generation prefers kudzu or wisteria.
As fall sets in, the bugs move from plants to sheltered areas to overwinter. These shelters often include the cracks and crevices of homes, which is when they become a serious nuisance to homeowners. The bugs show a preference for lighter-colored homes, especially white.
In spring, the bugs emerge from shelters to seek out plants to feed on. Adults mate and lay eggs almost immediately, and the hatching nymphs are responsible for much of the plant damage that occurs. The nymphs grow into adults within six to eight weeks and usually mate and lay eggs to complete the second generation.
Where Is the Kudzu Bug Found?
First detected in northeastern Georgia in late 2009, kudzu bugs have now spread across most of the southeastern U.S. They are not a problem (yet) in colder or dryer regions of the U.S.
Do Kudzu Bugs Bite?
This pest is too small to bite through the skin, but many people have a notable skin reaction when handling them. The bugs secrete a caustic substance that causes reddened welts on the skin.
Do Kudzu Bugs Help Control Kudzu Vine?
Contrary to popular belief, kudzu bugs were not deliberately introduced to control kudzu vine, nor are they provide any meaningful control for the invasive plant. Instead, kudzu seems to simply serve as an additional food source that puts soybean crops and other legumes at risk from massive bug infestations.