BLACKVILLE, S.C. (AP) — Kudzu — the ‘‘plant that ate the South’’ — has finally met a pest that’s just as voracious. Trouble is, the so-called ‘‘kudzu bug’’ is also fond of another East Asian transplant that we happen to like, and that is big money for American farmers.
Like kudzu, which was introduced to the South from Japan in the late 19th century as a fodder and a way to stem erosion on the region’s worn-out farmlands, this insect is native to the Far East. And like the invasive vine, which ‘‘Deliverance’’ author James Dickey famously deemed ‘‘a vegetable form of cancer,’’ the kudzu bug is running rampant.
Megacopta cribrari, as this member of the stinkbug family is known in scientific circles, was first identified near Atlanta in late October 2009. Since then, it has spread to most of Georgia and North Carolina, all of South Carolina, and several counties in Alabama.
And it shows no signs of stopping.
Kudzu and soybeans are both legumes. The bug — also known as the bean plataspid — breeds and feeds in the kudzu patches until soybean planting time, then crosses over to continue the moveable feast, says Tracie Jenkins, a plant geneticist at the University of Georgia.
On a recent sunny day, Greene and doctoral student Nick Seiter visited the 10-acre test field at Clemson’s Edisto Research & Education Center in Blackville, about 42 miles east of Augusta, Ga.
Starting in the middle of the field, Seiter walks down a row, sweeping a canvas net back and forth through the bean plants as he goes. Bugs cling to his pants and shirt, dotting his face like moles.
‘‘I feel like I’m wearing a bee beard over here,’’ he says. ‘‘It tickles.’’
At row’s end, Seiter pushes his hand up through the net. Bugs cascade over the edge and pool on the sandy soil at his feet.
The writhing pile makes a fizzing sound like a freshly opened soda.
‘‘Wow. It’s a couple of inches thick,’’ Greene says. ‘‘That’s just shy of a standard sample that we use to evaluate soybean insects ... and we’re looking at a couple of thousand bugs, easy.’’
The bugs secrete a caustic substance that smells like a cross between a commercial cleanser and an industrial lubricant. Greene says it’s unclear whether this is a defensive device, a way of locating each other in a field, or serves some other purpose.
Whatever it’s for, the secretions are potent enough to etch the bottoms of the plastic tubs he uses to ship samples to colleagues — and to stain the skin on Seiter’s blistered right palm a pale orange that can’t be washed off.
‘‘Self tanner,’’ he quips.
These insects are what entomologists call ‘‘true bugs,’’ meaning they have needle-like mouth parts that they use to suck on the plant. So rather than feeding on the pods or leaves, as corn ear worms and common stinkbugs do, kudzu bugs attack the stems and leaf petioles, literally draining the life out of the soybeans.
‘‘It’s reducing the ability of the plant to produce or to send photosynthate ... the food that the plant makes from the sun, to the fruit, to the seed,’’ says Greene. ‘‘So we’re going to have ... a reduced number of pods per plant, reduced number of seed per pod, and reduced seed size as well — all the above,’’ he says. ‘‘It’s not showy in terms of the damage that it does to the plant ... but it’s going to cause yield loss.’’
University of Georgia researchers have recorded losses as high as 23 percent in untreated fields.