The first emerald ash borer of Southeastern Pennsylvania was found in Bucks County last week. Officials are preparing to set up monitoring equipment this summer to see where else in the region the tree-killing beetle might lurk.

At the same time, the baseball bat-making company Louisville Slugger continues to watch the movement of the tiny beetle closely. The company, which provides about 60 percent of the bats for major league baseball, has used timber harvested from the New York/ Pennsylvania border area to make its bats for more than half a century.

If the beetle were to infect the company's forests, all of their ash trees would eventually die.

Company representative Brian Boltz said Louisville Slugger started to track the movement of the beetle about eight years ago when it was first discovered moving into Ohio.

"As it kind of horseshoes around our area, yeah, every little find worries me a little bit more," Boltz said. "But the main one was back in 2007 when they found it right outside of Pittsburgh because that was the first time it was ever found in Pennsylvania."

The beetle has been discovered as close as 20 miles from their forests, but Boltz is optimistic it might be decades before a true infestation takes hold.

Still, due to recent discoveries, including the one in Bucks County, the company will buy some wood from New England this summer. They plan to make test bats to determine the location of the best alternate timber supplies.

Donald Eggen of Pennsylvania's Bureau of Forestry said the beetle's larvae burrow into ash trees, cutting off the flow of nutrients and eventually killing them. Treatment with pesticides is possible but expensive.

"You can treat individual trees, but where this thing has hit, especially in the Detroit area, where it was first discovered, 99 percent of the ash trees have been killed," Eggen said.

Eggen expects nearly all of the ash trees in the Philadelphia area to die eventually now that a Southeastern Pennsylvania infestation has been discovered. Bucks is the 23rd county in the state to report an ash borer infestation.

Only about 4 percent of Pennsylvania's forest area is ash, but Eggen says there is a higher proportion in cities and urban parks.

The beetles have killed well over 50 million trees nationwide since they were first discovered in the Detroit area 20 years ago.