Monitoring and Evaluating Establishment of Introduced Parasitoids of Emerald Ash Borer in Tennessee: Panning for Parasitoids

The emerald ash borer (EAB), Agrilus planipennis, is an invasive species native to eastern Asia. The primary habitat and food source of EAB are ash trees of the genus Fraxinus. Since its initial discovery near Detroit, MI, in 2002, feeding on native ash trees by EAB has caused the deaths of millions of ash trees in the U.S. Following its discovery in Tennessee in 2010, open releases of introduced natural enemies of EAB (Spathius agrili, n ≈ 24,000, and Tetrastichus planipennisi, n ≈ 84,000) were conducted in eastern Tennessee. These releases were conducted at five sites in three counties: Cowan Park and Ramsey House in Knox County, Haven Hill and Miser Station in Blount County, and Lorino Park in Hamblen County. Beginning January 2015 after at least two years of releases, a study was initiated to monitor parasitoid establishment via pan trap collections. Pan traps (n = 10/site) consisted of small yellow plastic pans filled with diluted anti-freeze attached to selected trees within release sites. Traps were collected biweekly during colder months (January through March 2015, November 2015 through February 2016) and weekly in warmer months (April through October 2015). Results of pan trapping will be presented and discussed.