Wednesday, November 02, 2011

Kudzu killer

Nature often works in mysterious ways. Then again, sometimes she's very straightforward. The takeaway here is that she is persistent and will prevail in her efforts for achieving overall ecological integrity.

By any means necessary (GW)

Bug Battle: An Invasive Plant Now Faces Its Own Attacker


Insects From Asia Munch on Kudzu, a Vine That Has Grown on Some

By Valerie Bauerlein
Wall Street Journal
November 1, 2011

GRIFFIN, Ga.—Patti Bennett was looking out the window of her home office one morning two years ago when a swarm of green bugs flew out of the neighboring kudzu patch.

The invasive Kudzu vine has finally met its match. The problem? It's killer--the kudzu bug--is an invasive species, too. WSJ's Valerie Bauerlein reports from Griffin, Ga.

"I thought, 'What the hell is that headed at my house?' It was like a horror movie," says Ms. Bennett, a 53-year-old insurance underwriter who lives about an hour from Atlanta. She killed hundreds of bugs with spray, while thousands more released a musty, bittersweet odor in defense.

She scooped some bugs into a Tupperware container of alcohol and handed them to the local Home Depot specialist, an exterminator and a county agricultural agent.

Ms. Bennett was one of the first people in the South to report seeing Megacopta cribraria, an insect native to Asia that likely stowed away on a flight in 2009 and entered the U.S. through Atlanta's Hartsfield-Jackson International Airport, entomologists say.

Often a new bug brings nothing but bites and headaches for entomologists who race to limit the damage. But battle lines are being drawn over Megacopta cribraria.

The bug, which has spread from North Carolina to Alabama, kills kudzu—a picturesque but pesky green vine that was itself an Asian import. Over the next decade, the bug could munch up to a third of the eight million acres of the kudzu that blankets the South, says James L. Hanula, an invasive plant specialist with the U.S. Forest Service in Athens, Ga.

"I'm all for it," says Keith Brouillard, owner of Raleigh, N.C.'s Carolina Forestry, a consulting group that helps manage timber land for private owners. "Kudzu is a nuisance and almost impossible to get rid of." The vine is virtually impervious to herbicides, chain saws and even fire. Its roots can weigh 300 pounds and run 12 feet deep.

But the bug is also chewing up soybean stalks, reducing some yields recently by as much as a quarter, according to entomologists at the University of Georgia.

"Disappearing kudzu is a cultural problem," says John Shelton Reed, a sociologist and essayist on Southern life. "But disappearing soybeans is an economic problem."

Kudzu is celebrated in James Dickey's poetry, a long-running comic strip by the late Doug Marlette and on the cover of R.E.M.'s "Murmur" album.

A patch of kudzu was removed in a U.S. Forest Service test to estimate the effect of the 'kudzu bug' on the fast-growing plant.

"In Georgia, the legend says that you must close your windows at night to keep it out of the house," Mr. Dickey writes in "Kudzu." "The glass is tinged with green, even so."

Kudzu covers trees and fields from southern Virginia as far west as Arkansas and south to the Florida Panhandle. Researchers have spent 50 years looking for ways to control it.

The plant was brought over by the Japanese for an 1876 botanical exhibit but wasn't widely cultivated until the Great Depression, when New Deal-era federal workers planted the vine for erosion control. It quickly enveloped the rural South, growing as much as a foot a day in the steamy summer.

Not everyone detests it. Henry and Edith Edwards, who operate the Kudzu Cow Farm outside Rutherfordton, N.C., use it for goat feed, make jelly from its blossoms and sell roots to Japanese distributors who use it for health potions.

"Our soil and these gullies would be mud going to the Atlantic Ocean in a year or two," says Mr. Edwards, who insists at 87 that eating the protein-rich vine keeps him young. "Lord, have mercy, you can't imagine the South without kudzu. You'd cry big tears without it."

He and his wife recently spotted the bug at their farm and are worried about damage it could do.

Scientists with the U.S. Forest Service, who have been searching for an Asian insect that could quell kudzu without harming other plants, see potential in the bug. But the Forest Service doesn't plan either to help or impede it.

Meanwhile, entomologists are trying to figure out how to help farmers protect soybean plants. One entomologist went to Japan in search of a predator, with the most likely prospect a parasitic wasp that destroys kudzu bug eggs.

Daniel Suiter, a pest-control expert at the Griffin campus of the University of Georgia, is testing protocols for killing the bug with as few chemicals as possible.

A colleague, Wayne Gardner, is culturing killer fungi that could potentially be introduced in the wild.

Ms. Bennett's three-bedroom house in Hoschton, Ga., is now pictured in scholarly articles as ground zero for kudzu bug research.

Shortly after her initial report, Messrs. Suiter and Gardner drove 90 miles to Ms. Bennett's and found the bugs infesting kudzu behind her house. She mentioned that the bugs had also hopped on her silver Cadillac, which she regularly drove to an office an hour away.

"We just kind of went, 'Uh oh,'" Mr. Suiter says.

The UGA team sent samples to the Smithsonian Institution and confirmed that the bug, like kudzu, came from Asia.

The university's insect pest geneticist has since traced 250 samples of the kudzu bug found domestically back to one mother, dubbed GA-1. The entomologists theorize that GA-1 or her eggs most likely traveled from Japan, based on comparing GA-1's DNA with that of bugs found throughout Asia.

Research on the kudzu bug has trumped fire-ant and pecan weevil projects at the quiet Griffin campus. "We have an insect that had not been reported in the New World," Mr. Gardner says. "Many entomologists go through their career and never have that experience."

The bugs have recently started venturing out of kudzu patches as they seek places to hibernate for winter. In Georgia, the bugs have been smashing into windshields, lighting on exterior walls and smelling up soccer games and outdoor parties.

Ms. Bennett says some bugs recently flew on to her house but there were hundreds, not thousands as before. She suspects there are fewer bugs because much of the kudzu behind her house has been munched in prior years. She doesn't know how they made it to her subdivision, but says she feels bad about ending up as a "sort of a 'Typhoid Mary'" of invasive pests.

She's not the only one who may have given the bugs a ride. Entomologists say the bugs likely hopped on other vehicles and rode to spots in Georgia and the Carolinas, hastening their spread. Also, the hardy bugs likely got carried by weather.

"It's the stupid bugs' fault for picking my house," she says. "They would've gotten places anyway, I just helped them get there faster."

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