Wasps go urban in tree pest war - Minneapolis-St. Paul, MN

Wasps go urban in tree pest war | StarTribune.com

A new type of wasp is about to arrive in the Twin Cities. But it won't sting you. In fact, it's here to help.

Several thousand Chinese wasps will be released at five locations in Minneapolis and St. Paul the week of June 6 in hopes that they'll help stop the spread of the emerald ash borer, an insect threatening about a half million trees in the Twin Cities and nearly 1 billion statewide.

The wasps, some smaller than 1/8 inch, have long kept the emerald ash borer in check in China, where both are native. But they're only beginning to be used in the U.S., where the emerald ash borer wasn't even identified until 2002, after it had already killed millions of trees in Michigan, Ohio and Ontario. Their use has been approved by the U.S. Department of Agriculture.