DES MOINES – Emerald Ash Borer (EAB) has been positively identified in a residential tree in the city of Creston — making this the fifth location where the invasive beetle has been found in Iowa.
EAB kills all ash tree species and is considered to be one of the most destructive tree pests ever seen in North America.
The current EAB infestation was found as a result of an arborist contacting state officials about a suspect ash tree. Investigation by the Iowa EAB team members revealed characteristic galleries and D-shaped exit holes in dead branches and a partial adult beetle was positively identified by federal identifiers.
EAB infestations had previously been discovered in Allamakee County in May 2010, Des Moines County in July 2013, Jefferson County in August 2013 and Cedar County in October 2013.
A quarantine covering 25 counties in eastern Iowa was issued on Nov. 1 intended to slow the accidental movement of EAB by humans. An additional quarantine in response to this new confirmed infestation is being developed. A quarantine restricts movement of hardwood firewood, ash logs, wood chips and ash tree nursery stock out of the quarantined counties.
Most EAB infestations in the United States have been started by people unknowingly moving infested firewood, nursery plants or sawmill logs. The adult beetle also can fly short distances, approximately 2 to 5 miles.
“Preventive treatments next spring — mid-April to mid-May 2014 — are available to protect healthy and valuable ash trees within 15 miles of the known infested area,” said ISU Extension and Outreach Entomologist Mark Shour.
The reason preventative treatments are applied in the spring, Shour said, is because in the winter months trees are basically dormant. The treatments — which are highly successful when applied correctly — should be used in the spring when the product can be distributed throughout the tree.
To learn more about EAB and other pests that are threatening Iowa’s tree population, visit www.IowaTreePests.com.