Emerald Ash Borer Discovered in Sac County
Ash tree-killing insect confirmed in rural Schaller
DES MOINES, Iowa (Aug. 6, 2020) – The exotic emerald ash borer (EAB) has been detected in Sac County for the first time. EAB larvae were removed from underneath the bark of a tree in rural Schaller.
The destructive wood-boring pest kills ash trees by tunneling under the bark in an area that restricts the flow of water and nutrients. Infested trees typically die within two to four years.
Ash trees infested with EAB might exhibit canopy thinning, woodpecker damage, water sprouts from the trunk or main branches, serpentine (“S”-shaped) galleries under the bark, vertical bark splitting, and 1/8 inch D-shaped exit holes.
“The Sac County find came after a tree service contacted the Department,” said Mike Kintner, Iowa Department of Agriculture and Land Stewardship EAB and gypsy moth coordinator. “We are hopeful Iowans and people in the tree industry will be vigilant and report signs of EAB in new areas.”
The State of Iowa continues to track the movement of EAB on a county-by-county basis. Before a county can be officially recognized as infested, an EAB must be collected and verified by USDA entomologists. Iowa counties confirmed with this invasive pest now total 74 since the first detection in 2010.
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 soil moisture is critical for the effectiveness of any systemic insecticide movement in a tree. More details pertaining to treatment are available in Iowa State University Extension and Outreach publication PM2084, Emerald Ash Borer Management Options: https://store.extension.iastate.edu/product/13114. To find a certified applicator in your area, download PM3074, Finding a Certified Pesticide Applicator for Emerald Ash Borer Treatment, and follow the steps: https://store.extension.iastate.edu/product/14442.
The larval stage of the insect can unknowingly be transported in wood products such as firewood. The public can help limit the spread of EAB by using locally-sourced firewood where they are going to burn it. A federal quarantine prohibits the movement of firewood and ash material out of Iowa into non-quarantined areas of other states.
To learn more about EAB and other pests that are threatening Iowa’s tree population, please visit www.IowaTreePests.com.
For more information contact any of the following members of the Iowa EAB Team: