A new insect pest has spread north from Georgia into South Carolina. It is considered an invasive insect pest because it is from other parts of the world and had not been found in North America prior to 2009.

In 2009, University of Georgia researchers found the new insect pest — called the bean plataspid — in north Georgia.

The good news is that these bugs feed on kudzu and could possibly be a biocontrol agent for the invasive weed. In fact, they fancy kudzu so much that they should perhaps be called the ‘kudzu bug’. The bad news is that they also attack other legumes, especially soybeans.

These new insects are distant cousins to stink bugs that cause problems in cotton and soybeans around the Southeast.

Feeding damage on soybeans in North America has not yet been documented, but bean plataspids cause sucking damage on legume crops — similar to the way green and brown stink bugs feed. However, the bean plataspid feeds on stems and leaves rather than on pods and seeds.

Clemson University entomologist Jeremy Greene says, “The bean plataspid, Megacopta cribraria, has been found in 13 counties in South Carolina. It is likely to spread quickly to other areas of South Carolina,” he says.

Feeds on legumes

Greene notes this insect seems to prefer kudzu, but, it will feed on legumes in general, so it could be on other hosts, and it might be present but not yet detected in other counties.

“We need your help in documenting where this pest is and is not. If you are out and about and want to check patches of kudzu or soybean fields, please take GPS coordinates and note information about the presence or absence of these bugs in your area,” the Clemson scientist urges.

Greene stresses growers, crop consultants and others should take digital pictures or preserve specimens believed to be bean plataspids in vials of alcohol. These images or samples can be sent to the Edisto Agricultural Research and Extension Center in Blackville, S.C., for verification.

Greene warns anyone collecting samples of these pests to be careful when leaving an infested area because these insects can be transported very easily on your clothing and get into your vehicle.

The Clemson researcher says it is likely these new pests are in other South Carolina counties. He plans to ramp up scouting and research efforts to get a better idea how widespread these insects are and what damage they can do in the Palmetto state.

The bean plataspid is native to China and India. It is pea-sized, brown and has a large posterior. One characteristic is that it has a waddle when it walks. When challenged it flies well and can emit an odor similar to stinkbugs.

Found in China, India

In China, there are one to three generations per year. Adults over-winter and become active again in April. Bugs can be found in the fields until October. In some areas in India these bugs are known to be active and feed all year.

How these new invasive pests got to northeast Georgia isn’t certain. The most likely scenario is for the insect, or more likely eggs from the pest, came in via Atlanta’s Hartsfield-Jackson International Airport. It’s likely the pest has been around a few years, but only built up numbers high enough to be found in 2009.

Though all plant material brought into the U.S. is subject to inspection by APHIS, only a small percentage is actually checked — due to the volumn of people coming into and through the U.S. every day.

Though the exact biology of the bean plataspid isn’t known, it appears to have the capability of rapid reproduction. It also has a number of abundant potential legume hosts in the Southeast — not the least of which is kudzu.

Right now it’s a potential problem, but one that entomologists in Georgia, the Carolina’s and Virginia are watching closely.

e-mail: rroberson@farmpress.com