Parasitic wasps engaged in fight against emerald ash borer in Ohio

In 2002, people began seeing sick and dying ash trees in the Windsor/Detroit area, and after some investigations by the U.S. Department of Agriculture (USDA) inspectors, the cause was determined to be from an invasive insect called the emerald ash borer (EAB).
This exotic pest was likely brought over in shipping pallets from China in the 1990s. Since then, it has decimated native ash tree species throughout North America. They were first seen in northwestern Ohio the following year.
After determining that no such native insect would effectively prey upon EABs, selected species of parasitoid wasps from their native ranges in China, Korea, and Russia were targeted by the USDA to test for liberation into North America. Thus far, four species have been approved with more expected to follow.