It's prime time for the emergence of an extremely invasive insect that could be deadly to the Commonwealth's wood industry.

State officials are hoping a lure, in the form of a purple box, will help to eradicate the imported beetle before it destroys the species of tree that is most popular in regional manufacturing.

Emerald Ash Borer beetles have been discovered in 15 Pennsylvania counties, with three of the most recent counties confirmed July 1. A suspect sample found in Gregg Township, Union County, is being tested for confirmation.

The Emerald Ash Borer came from Asia and was first discovered around 2002 in Detroit, Mich., apparently imported through solid wood packing material on cargo ships.

"By the time they figured out what they had, the beetle had been there for 10 years," said Dr. Donald Eggen, forest health manager for the Pennsylvania Department of Conservation and Natural Resources, Bureau of Forestry, and chief of the division for Forest Pest Management.

The beetle was later discovered in Butler County in Pennsylvania in 2007, and made its way through several counties, said Jean Kummer, spokeswoman for the Pennsylvania Department of Agriculture.

That number is now 15, but officials believe there are more.

The quarantied counties also include Mifflin and Juniata, requiring neighboring Valley counties to undergo extensive study by the Pennsylvania Department of Agriculture and Bureau of Forestry.

Immigration problem

The emerald ash borer kills all species of ash trees, Eggen said, and once it infests a tree, it is 99.2 percent effective in destroying it completely within three years.

While in its native land, the beetle is not a problem, it is a huge one in the United States, since the nation's trees are not resistant to it, and the insect has no natural predators here, Eggen explained.

Purple panels

Survey crews began hanging nearly 6,000 purple panel traps from ash trees on May 21 in 21 counties in Pennsylvania, just before the prime emergence season for the adult beetles — the end of June and early July. The traps are to be removed the end of August.

In some counties, especially along the northern tier, these boxes are placed on a grid basis, one for every one and a half square-mile area. Though set up on an annual basis, these traps are not extremely efficient, Eggen said, so "if you do catch a beetle, it probably means there's a heavy infestation."

The lure is an oil, which smells like an ash tray. The beetles are also attracted to the color purple. The traps are covered with sticky material. They are placed into the crown of ash trees, or at the edge of the forest, since male beetles fly above the tree canopy to find females with which to mate.

Millions of trees

Eggen suspects many more infestations in neighboring counties will be discovered this summer.

Not good news for the state's rich hardwood industry, Kummer said.

Dave Whitten, director of exports at Bingaman & Son Lumber Inc., Kreamer, and chair of the Keystone Wood Products Association, said the beetle prefers White Ash trees, used especially for baseball bats, furniture, kitchen cabinets and flooring.

"Obviously, nobody in the industry wants the Emerald Ash Borer around, so most wood industry workers take an active role in identifying and eradicating it," Whitten said.

According to Eggen, ash trees may only account for four percent of Pennsylvania's forests, but that's a total of 330 million trees.

What to look for

So far, due to the diligence of the industry and the government working together, the negative effects of the insect have been kept to a minimum, Whitten said, and business hasn't been adversely affected.

However, the biggest problem is caused by unsuspecting homeowners, Whitten said, who transport ash firewood with the beetle inside.

"Everyone who spends any time in the woods should learn to identify it, and report it if they see it," he said.

According to the Department of Agriculture Adult emerald ash borers are dark green, one-half inch in length and one-eighth inch wide, and fly only from early May until September. Larvae spend the rest of the year beneath the bark of ash trees. When they emerge as adults, they leave D-shaped holes in the bark about one-eighth inch wide.

Woodpecker injury is a key indicator that trees may be infected with Emerald Ash Borer as the birds injure the trees while attempting to eat the beetle larvae.

Quarantine and control

State and federal Emerald Ash Borer quarantines restrict the movement from the quarantine area of ash nursery stock, green lumber and any other ash material, including logs, stumps, roots and branches, and all wood chips.

Due to the difficulty in distinguishing between species of hardwood firewood, all hardwood firewood and wood chips — including ash, oak, maple and hickory — are considered quarantined.

The beetle is responsible for the death and decline of more than 40 million trees in the United States.

There is no known practical control for this wood-boring pest other than destroying infested trees, the Department of Agriculture reports, but Eggen said there is a short-term approach that can be taken for ash trees in urban environments. Communities should do tree inventories, he said, and may actually inject the tree with systemic insecticide to eradicate the ash borer once it gets here.

People who suspect they have seen Emerald Ash Borer should call the toll-free pest hotline at (866)253-7189. More information is available at emeraldashborerinfo.org.

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