He said preliminary data from the University of Georgia show that heavy infestations will cause yield losses averaging 18 to 20 percent.
They don't eat beans but suck on stems and leaf-stalks. Insecticides used on stinkbugs will kill them.
"Our biggest challenge is educational," Catchot said. "They're not real damaging in low numbers, so we're encouraging our growers to not get upset when they see a bunch in the field. Wait until the insects have finished migrating into the field and then spray."
Adult kudzu bugs might move into a field for four to six weeks, and spraying too early will let later arrivals re-infest the field, Catchot said..
"We recommend that growers not make an application of insecticide until they scout and find one immature kudzu bug per sweep with the net," Catchot said. "Once you start picking up immature kudzu bugs, it's a good sign that the adult migration is over. One well-timed spray should be sufficient."
Like ladybugs, they're attracted to light surfaces and can cluster on buildings in the fall in great numbers, looking for a crevice through which they can enter to spend the winter in warmth. And they can squeeze in through a one-eight-inch gap.
"Exclusion rather than insecticide use is the best defense," Layton said. "Seal cracks, crevices and tears in screens over windows and gable or soffit vents. The house may have been sealed tight when it was built, but over time, crevices can develop."