May 20, 2011

Stink Bug Invasion Causing Terrible Crop Damage

The brown marmorated stink bug is believed to have caused millions of dollars in crop damage in the U.S. and could continue to wreak havoc.

The three-quarter-inch stink bug is native to Asia and was brought to Allentown, Pennsylvania in 1998.  The bug began appearing in mid-Atlantic orchards in 2003 to 2004 and exploded in population last year.

Stink bugs have been seen in 33 states, including every one east of the Mississippi River and as far west as California, Oregon and Washington.

"All that we do know for certain is that a tremendously large population went into overwintering in fall 2010. So, if they survived, there could be a very large population emerging in the spring," Tracy Leskey, a research entomologist at the U.S. Agriculture Department's Appalachian Fruit Research Station in Kearneysville W.Va, told the Associated Press (AP).

According to the U.S. Apple Association, the apple industry has been hit with $37 million in damage to growers in Maryland, Pennsylvania, Virginia and West Virginia. 

Mark Seetin, the association's director of regulatory and industry affairs, said this is the worst threat to farmers he has seen in his 40 years in agriculture.

The bug will feed on just about anything, including cherries, tomatoes, grapes, lima beans, soybeans, green peppers, apples and peaches.  It uses its mouth to pierce the skin of its host fruit or vegetables, leaving behind a spot that is disfigured and discolored.

Damaged fruit is safe to eat, but the blemishes reduce the prices of the food. 

Federal researchers have set up devices in nine commercial orchards in Maryland and West Virginia to monitor the bugs.

Other scientists from North Carolina to New York are trying to find a way to fight back against the pests.

U.S. Representative Roscoe Barlett started to demand federal action last year after hearing from orchard growers in his western Maryland district.

"If I was a mad scientist doing gene splicing and putting together a bug that would really be nasty and I was turning it loose on my enemy, I probably couldn't do a better job," Bartlett said in a statement to the AP. "One might define this thing as the bug from hell."

Researchers are considering long-term solutions, such as finding chemicals that can attract stink bugs to traps before they can feed on fruit. 

Some are researching to determine if importing the parasitic wasp, the stink bug's main Asian predator, could help the situation.

Growers who are looking for immediate help could use an insecticide called dinotefuran.  This chemical compounded is labeled by the Environmental Protection Agency (EPA) for use on vegetables, grapes and cotton, but not in orchards.

The EPA is reviewing an emergency exemption petition from the Virginia Department of Agriculture and Consumer Services that could allow the compound's use in orchards in Delaware, Maryland, New Jersey, North Carolina, Pennsylvania, Virginia and West Virginia starting in mid-July.

"When you spray the crop with completely legal, viable insecticide, you will kill the stink bug, but the problem is that you will do it today, and a few days later you will have another whole group of them migrating from the outside," tree-fruit entomologist Greg Krawczyk told the AP. "So they just keep moving."


On the Net: