Emerald Ash Borer

posted in Leisure Services on August 15, 2018

August 8, 2018 Emerald Ash Borer News Release

A destructive pest of ash trees was confirmed in Bremer County in Waverly in 2014. The emerald ash borer, an exotic pest from Asia, was first found in Iowa in 2010 and has now been detected in 61 Iowa 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.”

Since the dispersal of this beetle by natural flight is limited to only short distances, people serve as the mode of transportation involving longer distances. Beneath the bark in the larval stage, EAB can unknowingly be transported in firewood. Numerous other insects and diseases also can hitchhike in firewood. Iowans are encouraged to use locally sourced firewood, burning it in the same county where it was purchased.

Adult beetles begin to emerge from May to June and can be found throughout the summer months. The metallic-green beetle is slender and approximately 1/2 inch long. After emerging from a tree, the beetle leaves behind a telltale D-shaped exit hole approximately 1/8 inch in diameter.  

EAB-infested ash trees can include branch dieback in the upper crown, water sprouts along the trunk and main branches, vertical bark splits, D-shaped emergence holes, S-shaped tunneling under loose bark, as well as woodpecker damage. 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. Starved trees usually die within two to four years.

The City of Waverly as been systematically removing infested ash trees on public property along City streets, parks, and public spaces for the past 4 years. This year, the emphasis is on the Northwest part of the City where 104 ash trees have been identified.

If an ash tree is being treated chemically to prolong the life of the tree, then the Leisure Services Department is requiring a notice sent to City Hall by mail or email that the address is treating the ash tree and requests that the tree be taken off the list to be removed.

Ash trees on private property are the responsibility of the property owner and are encouraged to be removed sooner than later before the tree dies and becomes a hazard to property and person.  Currently, there are no programs to reduce the costs to the property owner of removing ash trees on private property. 

The State of Iowa continues to track the movement of EAB on a county-by-county basis.

At this calendar date, the treatment window for soil-applied preventive treatment measures (soil injection, soil drench or granular application) and basal bark sprays has ended. Trunk injections can be done now through the end of August if a landowner is interested in protecting a valuable and healthy ash tree within 15 miles of a known infestation.

Good ground moisture is essential for systemic insecticide movement in a tree. Full details are available in Iowa State University Extension and Outreach publication PM2084, Emerald Ash Borer Management Options. To find a certified applicator in your area, download PM3074, Finding a Certified Pesticide Applicator for Emerald Ash Borer Treatment, and follow the steps.

To learn more about EAB and view maps of its distribution, please visit http://www.iowatreepests.com.

For more information, contact Bremer County ISU Extension or Waverly Leisure Services.

Submitted by: Tab Ray, LS Director, 352-6263

A high quality of life, friendly and progressive merchants, and a college town atmosphere; this is Waverly, Iowa.