Emerald ash borer spreads to 92nd Iowa county

A foreign beetle whose larvae kill ash trees was recently discovered in Kossuth County, one of the few counties in Iowa not previously infested, according to the Iowa Department of Agriculture and Land Stewardship.

The emerald ash borer was first detected in Eastern Iowa in 2010. Since then it has spread to a total of 92 of Iowa’s 99 counties.

The beetle is native to Asia and was found in the United States, in Michigan, in 2002. Its larvae eat the inner bark of ash trees and can kill them in two years. The beetles’ spread is accelerated by people transporting them over long distances, including by hauling infested firewood.

The detection in Kossuth is the eighth in a new Iowa county this year. The remaining counties without a detection — mostly in northwest Iowa — include: Emmet, Mitchell, Monona, Osceola, Palo Alto, Plymouth and Woodbury.

Indications of a tree infestation include fewer leaves, sprouts from the trunk or large branches, meandering tunnels under the bark, split bark, woodpecker damage and smallish D-shaped holes in the bark where the beetles emerge.

Those who suspect an infestation can report it to the state at (515) 725-1470.

This article first appeared in the Iowa Capital Dispatch.