Emerald Ash Borer Confirmed in Iowa County, Iowa

Iowa now has 35 infested counties after discovery at Lake Iowa Park

September 19, 2016, 9:00 am | Dustin Vande Hoef, Kevin Baskins, Laura Sternweis

Emerald Ash BorerDES MOINES, Iowa – Emerald ash borer, a very destructive, exotic insect pest of ash trees, has been confirmed in Iowa County. This finding brings the total to 35 counties in Iowa. On a national scene, EAB has been found in 28 states and has killed tens of millions of ash trees.

The recent Iowa discovery took place at Lake Iowa Park (Iowa County Conservation Board) after staff alerted the Iowa EAB Team of some ash trees showing signs and symptoms of EAB attack. Following further investigation, insect samples were collected and later positively identified as EAB by a federal identifier.  

“It would be pretty realistic to say that emerald ash borer did not make its way to Lake Iowa Park on its own, but by campers hauling in firewood,” said Mike Kintner, Iowa Department of Agriculture and Land Stewardship EAB and gypsy moth coordinator. “Southeast Iowa appears to be the area hit hardest in the state by EAB, so infested firewood movement from a nearby county could very well have been the contributing factor.”

The Iowa EAB Team strongly urges Iowans to use locally sourced firewood, burning it in the same county where it was purchased. Firewood is a vehicle for the movement of EAB; too many infestations in the United States have started by people unknowingly transporting infested firewood.  

The adult beetle is metallic green and only about one-half inch long and slender, making it difficult to recognize in the landscape. The larval stage of this wood-boring insect tunnels under the bark of ash trees, disrupting the flow of water and nutrients and ultimately causing the tree to die. EAB-infested ash trees display canopy dieback beginning at the top of the tree and progressing downwards, S-shaped feeding galleries under dead or splitting bark, D-shaped exit holes, water sprouts (along the trunk and main branches) and increased woodpecker activity to the bark.  

At this calendar date, the window for all preventive treatments has closed. If a landowner is interested in protecting a valuable and healthy ash tree within 15 miles of a known infestation, he or she should have landscape and tree service companies bid on work, review the bids this fall/winter and treat beginning spring 2017 (early April to mid-May).

The State of Iowa will continue to track the movement of EAB on a county-by-county basis. Before a county can be officially recognized as infested, EAB must be collected by a member of the Iowa EAB Team and verified by USDA entomologists.

To learn more about EAB and other pests that are threatening Iowa’s tree population, please visit www.IowaTreePests.com. Please contact any of the following members of the Iowa EAB Team for further information:

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