DES MOINES, Iowa – The emerald ash borer (EAB) has been confirmed in four more Iowa counties.

The Iowa Department of Agriculture and Land Stewardship says the pest from Asia was found in samples collected in Buchanan, Hamilton, Hardin, and Pottawattamie counties. The destructive insect was first detected in the state in 2010 and has now been found in 61 counties.

“June is typically the time of year we receive a surge in phone calls about poorly looking ash trees. We urge people to continue to report suspicious symptoms in counties that are not yet known to be infested,” said Mike Kintner, Iowa Department of Agriculture and Land Stewardship EAB and gypsy moth coordinator. “People can really help minimize the spread of this pest by not giving it a ride in infested firewood between counties or from home to campsite.”

EAB larvae kill ash trees by tunneling under the bark and feeding on the part of the tree that moves nutrients up and down the trunk. Infected trees usually die within two to four years.

State officials say the time for preventive treatments to the soil and bark has passed, but injections to the trunk can be done through the end of August to protect ash trees within 15 miles of a known infestation.