DES MOINES, Iowa – The Iowa Department of Agricultural and Land Stewardship says a destructive insect has been found for the first time in Cerro Gordo and Webster counties.

Emerald ash borer (EAB) larvae has been collected from trees in Mason City and Fort Dodge. EAB feeds under the bark of ash trees during its larval stage, which damages and eventually kills the trees by disrupting the transport of water and nutrients. Infested trees typically die within two to four years.

EAB has now been confirmed in 73 Iowa counties.

“Many areas of the state have, unfortunately, already suffered the consequences of this destructive pest, but we continue to focus on tracking emerald ash borer in counties where it has not yet been confirmed,” says Mike Kintner, Iowa Department of Agriculture and Land Stewardship EAB and gypsy moth coordinator. “Knowing the whereabouts of this pest helps with treatment recommendations in immediate and surrounding areas.”

It is too late in the year for treatments to the soil or basal bark sprays to kill the insects. State officials say 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.

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.

Anyone who suspects an infested ash tree in a new location is encouraged to contact one of the following:

• Iowa Department of Agriculture & Land Stewardship, State Entomologist Office: 515-725-1470
• Iowa State University Extension and Outreach, Entomology: 515-294-1101
• Iowa Department of Natural Resources: 515-725-8453