The Associated Press

COLUMBUS - Government officials are considering an ambitious plan to contain the infestation of a tree-killing beetle by cutting down ash trees in a miles-wide swath across Ohio, Indiana and Michigan.

The exact route has not been determined, but the goal is to create a natural barrier that could extend in a semicircle south from Michigan into northwestern Ohio and northeastern Indiana, according to the Ohio and U.S. agriculture departments and the Indiana Department of Natural Resources.

The emerald ash borer has wiped out millions of ash trees in southeast Michigan. It also has been found in Ohio and northeast Indiana.

The barrier, in theory, would stop the beetle from spreading from its core infestation in Detroit.

The plan is similar to an "ash-free zone" created by Canadian officials to keep the bug from spreading to Windsor.

"They actually cut down every ash tree in a zone 6 miles wide," said Sharon Lucik, spokeswoman with the U.S. Animal Plant and Health Inspection Service in Brighton, Mich.

With pesticides ineffective, it's necessary to destroy ash trees so the beetle won't be able to find food. The barrier would be 3 to 6 miles wide because it's believed the ash borer doesn't travel farther than a half mile on its own.

U.S. Forestry Service maps will be used to determine the number of ash trees in the zone, Lucik said.

The cost of creating the barrier hasn't been estimated. The U.S. Department of Agriculture plans to spend up to $43.4 million on ash borer eradication efforts this year.