The Daily Times

Researchers with the University of Tennessee are investigating whether parasitic wasps can be used to battle the emerald ash borer that threatens millions of trees across the country.Greg Wiggins, a research assistant professor with the UT Department of Entomology and Plant Pathology, visited two sites in Blount County and released about 1,500 of the wasps.

“We’ve been making releases periodically throughout the summer. This is our fifth release,” Wiggins said in an interview. The emerald ash borer was first discovered in the U.S. in Michigan in 2002 and has steadily spread from there, damaging ash trees throughout the country.

The half-inch-long beetle lays eggs in bark crevices on all species of ash. Upon hatching, larvae burrow under the bark, creating feeding tunnels that interfere with the tree’s ability to transport nutrients and water. It gradually starves and eventually dies.UT researchers are investigating whether two species of parasitic wasps, S. agrili and T. planipennisi, can be used to control ash borer populations. The wasp populations will be monitored to see if they can become established in the local environment.

“It’s hard to tell because this is the first year we’ve done it,” Wiggins said. “It usually takes these types of organisms three to five years to establish. We’ll continue to monitor them over the next three years to see how well they are establishing and spreading in the site.”So far, more than 4,000 wasps have been released at four sites in Blount, Claiborne and Knox counties in 2012.

The presence of invasive emerald ash borer beetles has been confirmed in Blount County and Great Smoky Mountains National Park.

The spread of emerald ash borer beetles primarily results from transport of infested logs and firewood. A GSMNP-wide ban remains in effect for any firewood originating from a location for which a federal or state quarantine is in effect. A list of all quarantined areas may be found at http://www.nps.gov -counties.htm