MERION, Pa. -

A destructive pest attacking Ash trees across the country is doing damage in Pennsylvania.

Before the insect can spread even more, experts are taking steps to stop it.

The picturesque Barnes Foundation Arboretum is filled with thousands of species of trees and plants. But on the more than 12 acres in Merion, Montgomery County, there is a threat.

"Today we're doing some preventative treatments for the emerald ash borer," said Drew Lehrian, Barnes Foundation head gardener.

The emerald ash borer is a beetle wreaking havoc on Ash trees across the country.

Lehrian said, "Bucks County is our closest location that it's been confirmed and basically what we're doing is we're treating our ash trees so they don't get the borer."

"What it will do, it will come through, the borers get into the tree, it starts to eat the tree from the inside out basically," he explained.

A treatment was injected into the trunks to protect the trees against the pest.

"We're preventively treating about half a dozen specimen right now. If the threat becomes bigger and faster, we'll start treating probably upwards of 15," said Lehrian.

According to emeraldashborer.info, it's considered North America's most destructive forest pest ever. If not addressed, information on the site warns it will become a multi-billion dollar problem in the United States.