MARYVILLE, Tenn. — Researchers at the University of Tennessee are investigating whether parasitic wasps can be used to kill the emerald ash borer, a beetle that is threatening millions of trees across the country.

The invasive emerald ash borer has been confirmed in Blount County and the Great Smoky Mountains National Park, but researchers have unleashed about 4,000 wasps in East Tennessee to try and control the spread of the beetle that has been killing ash trees.

Greg Wiggins, a research assistant professor at the UT Department of Entomology and Plant Pathology, told The Daily Times ( http://bit.ly/UjCrwd ) that they’ve released two species of the parasitic wasps at spots in Blount, Claiborne and Knox counties.

Wiggins said it usually takes three to five years to establish and spread the wasp populations.

Information from: The Daily Times, www.thedailytimes.com