A small, beetle-like insect known primarily for the foul smell it emits when crushed poses a potentially devastating threat to New Jersey farms.
New Jersey agriculture officials say the brown marmorated stink bug — or stink bug for short — could potentially cause tens of millions of dollars in damage to fruit and vegetable crops in the state this year.
The stink bug threat is so new to the state that agriculture officials say they can only guess at this year’s potential crop damage. They nonetheless estimate that the bugs could destroy more than $40 million worth of apple, peach, tomato and green pepper crops that were worth about $117 million in 2010. One Rutgers University estimate sets a potential 60 percent loss to the state’s peach crop this year.
Researchers with Rutgers University’s New Jersey Agricultural Experiment Station say the state’s stink bug threat is greatest in South Jersey. Field study teams found the insects are concentrated in just about all of Salem and Gloucester counties and the western end of Cumberland County.
Should the bugs move out of that region, agriculture officials say, the fruit-loving insects could threaten New Jersey’s blueberry farms, which last year produced 49 million pounds of the fruit worth $62.5 million. New Jersey is the country’s fourth-largest blueberry-producing state, and thousands of acres of blueberry farms are located in western Atlantic County, a few miles from where the stink bugs are concentrating in Cumberland County.
Stink bugs essentially suck liquid from fruits and vegetables and leave some of their saliva behind. That saliva breaks down the fruit, leaving produce such as peaches and apples with brown, mushy interiors and creating a product that customers will not buy. Rutgers researchers said that kind of damage could cause farmers to lose about 70 percent of the apples that wind up in storage this year.
What makes the situation worse is that researchers say there is no way to really stop the stink bug threat.
Jack Rabin, the agriculture experiment station’s executive director, said the stink bugs — which are native to China, Japan and the Korean peninsula and entered the United States via an airport in Allentown, Pa., in 1996 — have no natural predators here. The bugs also are resistant to pesticides used as part of integrated pest management systems that took years to develop to protect New Jersey farms from the threat of domestic insects and weeds, he said.
Rabin said Rutgers researchers who entered fields just sprayed with regular doses of pesticides found what looked like dead stink bugs on the ground.
“Then you’ll stand there and watch their legs move again,” Rabin said. “Then they flip over and move on. It’s difficult to kill with agricultural chemicals. You almost have to hit them with something.”
Rabin said that while researchers are moving quickly to find an appropriate pesticide, it “may take years to come up with a way to really control them.”
Some agriculture officials are pinning hopes of controlling the stink bugs on the use of their native predators.
Carl Schulze, director of the state Department of Agriculture’s Division of Plant Industry, said U.S. Department of Agriculture personnel are searching for stink bug predators overseas. Those predators could eventually undergo testing at state agriculture laboratories in Ewing Township, Mercer County, and then possibly undergo some field tests, to determine if those predators can stop the stink bugs without causing an additional threat to the state’s agriculture, he said.
But the final determination will take time that farmers may not have.
“I don’t know whether it will be a year or three years or five years,” Schulze said. “Hopefully, it will be sooner rather than later.”
South Jersey farmers are on the lookout for stink bugs.
At Sunny Slope Farms in Hopewell Township, Cumberland County, field crews regularly search 1,000 acres of apple and peach trees for the insects, farm field supervisor Ron Thomas said.
“A lot of hands-on monitoring,” Thomas said. “So far, we’ve seen a few egg masses. The adults, we haven’t seen. We don’t have any damage yet.”
Thomas said Sunny Slope staff did not realize until last year that stink bugs were responsible for damaging some of the apple and peach crops. He said farm staff is working closely with researchers to determine which pesticides can at least contain the bugs and limit future damage.
“We’re very concerned that it’s going to be an expensive pest to control, if it’s even controllable,” he said.
Workers also are combing the 1,400 acres on which Atlantic Blueberry Co. grows blueberries in Atlantic County.
“We have scouts that scout daily,” said Bobby Galletta, one of the company’s owners. “So far, we haven’t found anything. We’re concerned, but we don’t know what they will do.”
Officials in Pennsylvania, Maryland, West Virginia and Virginia, where the stink bug problem is at its worst, know the destruction the insects can cause.
Agriculture officials said stink bugs are to blame for an 18 percent loss in apple harvests in those states last year. Those losses totaled about $37 million. Rabin said farmers in some parts of those states lost 100 percent of their fruit and vegetable crops when they took no action against stink bugs, while farmers who used heavy applications of pesticides still lost as much as 60 percent of their crops.
New Jersey has some native stink bugs, but the species is primarily harmless and beneficial, Rutgers researchers say. The native bugs control pests that can cause crop losses, and the damage the native stink bugs do to crops is minimal, amounting to things such as small yellow spots on tomatoes.
Researchers said the Brown Marmorated Stink Bug has been in New Jersey for about 13 years. Noticeable agricultural damage, particularly in peaches and peppers, related to the stink bug only started occurring about three years ago as a late-season problem.
Rabin said the stink bugs find shelter in homes, garages, barns and other structures. They also “overwinter” in places such as attics and come out again in warmer weather, he said.
Rutgers officials said the stink bugs are not dangerous to people and cause no damage to homes, adding that many of the stink bugs found inside a home will likely starve to death.
As for the smell, Joseph Ingerson-Mahar, who coordinates the vegetable integrated pest management system for Rutgers Cooperative Extension, said the material responsible for the odor is found in the stink bug’s thorax. The material is released when the thorax is crushed, and there is also evidence indicating stink bugs release the material when they are disturbed, he said.
Rutgers Cooperative Extension this year started using traps to try to track stink bugs in the state. There are 65 traps in New Jersey, including 30 in the southern part of the state.
Ingerson-Mahar on Wednesday checked one of the traps on a 585-acre potato farm off Columbia Highway in Stow Creek Township, Cumberland County. The trap in two days caught a number of scarab beetles, June bugs and other insects who entered the device in part after being disoriented by an attached black light.
While Ingerson-Mahar found only one stink bug, he said that small number is deceptive. The numbers vary by week, he said, and the figure will likely increase in August.
Rabin said those stink bug counts and other research will hopefully create a program that can deal with the insects.
“We’re preparing ourselves,” he said.
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