The Minnesota D-N-R, Department of Agriculture, and U.S. Forest Service have expanded a biological control program to slow the spread of emerald ash borer (EAB). Since 2010, three species of non-stinging wasps have been released at 55 sites statewide. 

These wasps target E-A-B at different life stages and are safe for humans and the environment. This summer, over 5 thousand wasps were released across 200 acres in the Chippewa National Forest, totaling 84 hundred over two years. No new infestations have been reported in the forest. 

E-A-B, first found in Minnesota in 2009, kills ash trees by feeding under the bark. The state is home to an estimated 1 billion ash trees, with many more in urban areas.