Kudzu bugs, slightly larger than ladybugs, are invasive pests that emerged in the United States in 2011. These bugs, known for their square and flattened bodies, not only damage the notorious kudzu plant but also pose a threat to agricultural crops like soybeans.
The need to control kudzu bug populations is crucial to protect native ecosystems and maintain crop health. These pests, which are attracted to kudzu and other legumes, not only feed on leaves and stems but also damage crops by injecting a toxic saliva that inhibits plant growth. Various techniques and products are available for homeowners and farmers to manage and keep kudzu bugs at bay.
If you’re struggling with a kudzu bug infestation, you might want to try a variety of approaches: chemical control using insecticides, manual removal, or natural predators. It’s essential to choose the method that best fits your needs while minimizing harm to the environment and maintaining your garden’s health.
Understanding Kudzu Bugs
The kudzu bug is an invasive insect with an olive-green color and brown speckles. It is slightly larger than a ladybug and has a square, flattened body 1. Being a “true bug,” it possesses piercing-sucking mouthparts 2.
Kudzu bugs overwinter in protected areas and reemerge in the spring to reproduce and feed on various plants. They are commonly known to feed on legumes, soybeans, wisterias, and vetches 3.
Asia and United States Distribution
Originally from Asia, the kudzu bug was first introduced to the United States in 2009. It quickly spread throughout most North Carolina counties and to various southern states, causing significant damage to agricultural crops such as soybean 4. The kudzu bug has also found its way to the central regions of the United States 5.
Kudzu Plant and Its Connection to Kudzu Bugs
Kudzu (Pueraria montana) is an invasive vine originally from East Asia that has become a significant problem in the United States, particularly in the South, where it can disrupt native ecosystems and threaten natural resources. Kudzu plants form thick mats on the ground and can climb trees, with stems that can grow up to 10 inches in diameter and taproots that can reach 7 inches in diameter.
Some characteristics of kudzu:
- Leaves are alternate and compound with three broad leaflets up to 4 inches across
- Mature bark is rough, rigid, and dark brown
- Resistant to many herbicides
The Role of Kudzu in Kudzu Bug Infestations
Kudzu bugs are an accidentally introduced species, not intentionally introduced to control kudzu. The bugs, which now pose an economic threat to soybeans, were likely brought to the U.S. by hitchhiking on a commercial airplane. Once in the U.S., they spread throughout the country and became a nuisance on kudzu plants.
Key features of kudzu bug infestations:
- Found mainly in the southeastern United States
- Can damage soybean crops
- Quick and widespread establishment
Kudzu Bug Diet
Kudzu bugs have a particular diet that primarily consists of feeding on kudzu plants, making the invasive vine an ideal habitat for the bugs. As a consequence, both the kudzu plants and kudzu bugs present challenges to native ecosystems and can disrupt agricultural activities.
A comparison of kudzu and kudzu bugs:
|Kudzu (Invasive Plant)
|Kudzu Bug (Invasive Pest)
|Feeds on kudzu plants
|Resistant to herbicides
|Causes crop damage
|Disrupts native ecosystems, natural resources
|Found mainly in the southeastern U.S.
Preventing Kudzu Bug Infestations
Controlling Kudzu Plants
Kudzu bugs are attracted to their namesake plant, kudzu. By controlling the growth of kudzu plants near your home, you can help prevent infestations. The USDA recommends using combined management programs for faster results. Some effective methods include:
- Prescribed burning
- Disk harrowing
Following these practices reduces the likelihood of kudzu bugs invading your lawn and garden.
Sealing Gaps and Openings
Kudzu bugs can enter your home through small gaps and openings. Seal potential entry points to prevent infestations. Examples include:
- Caulking cracks in walls
- Plugging holes in vent systems
- Fixing damaged window frames
When sealing gaps, wear gloves to protect your hands from any insects that may already be inside.
Insect Screens and Door Sweeps
Adding insect screens and door sweeps can be an extra layer of protection against kudzu bugs. In areas like North Carolina, South Carolina, and Georgia, where these bugs are common, having a screen over windows and doors is essential.
Consider installing screens made from finer mesh materials for better protection. Door sweeps, too, should fit snugly against the bottom of your door to prevent entry.
|Requires proper fit
Using these tools provides an additional line of defense, making your home less welcoming to kudzu bugs and other pests.
Getting Rid of Kudzu Bugs
Manually removing kudzu bugs can be time-consuming but effective for small infestations. Keep in mind:
- Wear gloves to avoid skin irritation
- Use tools (e.g., vacuum, tweezers) to collect bugs from plants
Chemical treatment is an option for more extensive infestations. Consider:
- Bifenthrin: a common insecticide for kudzu bugs
- Herbicides like glyphosate: effective against kudzu vines
- Quick results
- Efficient for large-scale infestations
- Possible harm to non-target organisms
- Some chemicals may be toxic to humans and pets
Instead of chemicals, try:
- Vinegar: A natural, eco-friendly alternative to herbicides
- Soap water: A less-toxic solution for treating plants
For biological control:
- Introduce natural predators of kudzu bugs (e.g., parasitic wasps)
- Environmentally friendly
- Lower risk to non-target organisms
- Slower results
- May require repeated treatments
Impact of Kudzu Bugs on Agriculture
Soybeans and Legume Plants
Kudzu bugs are known to feed on a wide variety of legumes, including soybeans, peas, green beans, wisteria, and some vetch species. Their piercing-sucking mouthparts extract nutrients from the plants, causing damage and reduced growth.
These pests are particularly attracted to soybean crops, where they can cause significant damage.
Kudzu bug infestations can lead to substantial yield losses in affected legume crops. The severity of yield loss depends on the infestation level and the effectiveness of control measures implemented.
Examples of yield losses:
- Moderate infestations cause 18% yield loss in soybeans
- Severe infestations result in up to 60% yield reduction
Effective control measures are essential to minimize the impact of kudzu bugs on agriculture. There are several methods to consider:
- Chemical control: The use of insecticides to manage kudzu bug populations
- Planting resistant varieties: Select legume cultivars that are less susceptible to kudzu bug infestation
- Crop rotation: Change the type of plants grown on a specific area to disrupt the pests’ life cycle
- Cultural practices: Maintain crop hygiene and field cleanliness to reduce kudzu bug populations
Pros and Cons of Chemical Control:
|Rapid reduction of pests
|Can cause harm to beneficial insects
|Easy application process
|Potential development of resistance
|Widely available products
To get rid of kudzu bugs, consider these methods:
- Chemical control: Use approved insecticides such as neem oil on affected plants.
- Mechanical control: Remove kudzu and other legumes to reduce their habitat.
- Biological control: Encourage the growth of kudzu bug predators, like Japanese kudzu bugs, by maintaining a diverse ecosystem.
When choosing a method, consider each one’s advantages and disadvantages:
|May harm non-target species, environmental impact
|Eco-friendly, no chemicals
|Labor-intensive, may need repeated treatments
|Slow progress, may not always be effective
As you implement these methods, monitor the progress to ensure effectiveness and make adjustments as needed. Remember that patience and persistence are key in combating kudzu bugs.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Lablab Bug
Subject: They’re Everywhere!
Location: Holden Beach, NC
May 25, 2013 5:08 pm
These bugs are on our porch railings, lined up in a conga line. Touch them and they fly away!
They form lines or groups. Birds seem to ignore them.
Signature: Tom on the Beach
Dear Tom on the Beach,
This invasive, exotic species is a recently introduced True Bug from China known as the Lablab Bug, Kudzu Bug or Bean Plataspid, Megacopta cribraria. It is a known pest on several crops including soybeans and its one benefit is that it feeds on another invasive species, Kudzu. See the University of Georgia article entitled Megacopta cribraria as a Nuisance Pest for more information.
Letter 2 – Lablab Bug
Subject: Mystery Beetle
Location: Deatsville, Alabama
October 12, 2013 2:23 pm
I was watering my potted gardenia tree and when I rinsed down the leaves a swarm of these took to the air. I couldn’t find a match for them in any bug book I had, nor via googling them on the internet. They aren’t very big, about 1/4 of an inch. For size comparison, one of the pictures was taken on my screen door; the mesh being regular screen mesh. They do fly, but they don’t appear to bite. The gardenia seems to have suffered no damage but I’m not sure having swarms of these critters on any plant can be good?
The reason you could not locate the Lablab Bug or Kudzu Bug, Megacopta cribraria, in your bug books is that it is a recently introduced, exotic species that feeds on Kudzu, however it does not limit itself to Kudzu. Since the Lablab Bug is a True Bug with piercing mouthparts designed to suck fluids, you would not notice typical damage like chewed leaves, but a large number of individuals feeding on the same plant could seriously compromise it.
Thank you for getting back to me about this bug. I can understand now why I couldn’t find it in any of my bug/insect books. It sure doesn’t sound like a helpful garden bug; quite the contrary. I don’t know why it fell in love with my gardenia, but I’ll be keeping a close eye on the plant and discouraging further infestation, Apparently these critters do not like being hosed down with a water hose 😉
Letter 3 – Lablab Bug
Subject: small brown bug like a lady bug
Location: Southeast region
October 27, 2013 11:30 am
I first noticed one of these bugs in my house on my couch. Then after taking my children outside to play, they were all over my kid’s plastic swingset. We live in Alabama surrounded by lots of undeveloped land. We have lived here for four years, and this is the first time I have noticed this bug. It is about the same size as a lady bug but not as round and it is a dark brown color. It also flies. What kind of bug is this and is it dangerous to my kids? Thanks!
The Lablab Bug is a recently introduced, exotic species that fees upon another exotic introduction, Kudzu. We expect the Lablab Bugs will proliferate wherever Kudzu can be found. Lablab Bugs are not dangerous to humans, but they are a nuisance when they are plentiful, which is nearly always. We will be postdating your submission to go live in early November while we are away from the office.