Ash trees in Jefferson County are getting some relief from harmful emerald ash borers, or EAB. The EAB is not native to North America, but was accidentally introduced from Asia, and natural enemies did not accompany them. Now the United States Department of Agriculture is stepping in to introduce those enemies to keep the EAB population in check.
The beneficial insects, two species of stingless wasps native to Asia, have already been released in 23 states where excess EAB have been detected, and Jefferson County is the first in Iowa to utilize the wasps. Both species are harmless to humans, but attack EAB eggs and larvae, preventing them from overtaking ash trees.
According to the USDA Forest Service, Iowa has around 55 million ash trees in both rural and urban areas. As they monitor the success or failure in Jefferson County, additional sites will be approved for similar releases.