Yang is a gregarious larval endoparasitoid native to China and has been introduced to the United States since 2007 for classical biological control of the invasive emerald ash borer, Agrilus planipennis
Fairmaire, an exotic beetle responsible for widespread ash mortality. Between 2007-2010, T. planipennisi
adults (3,311-4,597 females and ~1,500 males per site) were released into each of six forest sites in three counties (Ingham, Gratiot, and Shiawassee) of southern Michigan. By the fall of 2012, the proportion of sampled trees with one or more broods of T. planipennisi
increased to 92 and 83% in the parasitoid-release and control plots, respectively, from 33 and 4% in the Þrst year after parasitoid releases (2009 fall for Ingham county sites and 2010 for other sites). Similarly, the mean number of T. planipennisi
broods observed from sampled trees increased from less than one brood per tree in the first year after parasitoid releases to 2.46 (at control plots) to 3.08 (at release plots) broods by the fall of 2012. The rates of emerald ash borer larval parasitism by T. planipennisi
also increased from 1.2% in the first year after parasitoid releases to 21.2% in the parasitoid-release plots, and from 0.2 to 12.8% for the control plots by the fall of 2012. These results demonstrate that T. planipennisi
is established in southern Michigan and that its populations are increasing and expanding. This suggests that T. planipennisi
will likely play a critical role in suppressing emerald ash borer populations in Michigan.
natural enemy introduction
parasitoid release and establishment
Duan, Jian J.; Bauer, Leah S.; Abell, Kristopher J.; Lelito, Jonathan P.; Van Driesche, Roy. 2013. Establishment and abundance of Tetrastichus planipennisi (Hymenoptera: Eulophidae) in Michigan: potential for success in classical biocontrol of the invasive emerald ash borer (Coleoptera: Buprestidae). Journal of Economic Entomology. 106: 1145-1154.