U.S. Deploys Wasps To Slow Outbreak of Emerald Ash Borers

The U.S. Department of Agriculture (USDA) is releasing hundreds of thousands of parasitic wasps in northern states in the hopes of blunting an outbreak of an alien insect, the emerald ash borer, that has killed an estimated 60 million ash trees nationwide. In a video produced by Michigan State University’s Knight Center for Environmental Journalism, USDA entomologist Deborah McCullough calls the emerald ash borer “the most destructive forest insect ever to invade North America.” The ash borer is believed to have entered the U.S. from China in the early 1990s, most likely in packing crates carrying goods to Detroit. The insect has since spread to a handful of states, killing at least 40 million ash trees in southern Michigan alone. McCullough said the economic damage from the outbreak could top $20 billion in the next 10 years. To combat the disease, the USDA is releasing parasitic wasps that lay eggs that kill the eggs, larvae, and pupae of the ash borers. The wasps are now being released in Michigan, Minnesota, Indiana, Illinois, and Ohio and will be released next year in Wisconsin, New York, Pennsylvania, and Tennessee.