Emerald ash borer detected in five more Iowa counties

The emerald ash borer has been detected in five more Iowa counties, putting the total number of impacted counties at 50, state officials announced Thursday.

The invasive species has been found in Benton, Buena Vista, Floyd, Howard and Warren County, meaning that now, more than half of Iowa counties are impacted, according to the Iowa Department of Agriculture and Land Stewardship. Experts say the pest, which destroys ash trees, is most frequently spread by the transport of infested firewood.

'Unfortunately, emerald ash borer is going to continue to trek on across Iowa,” said Mike Kintner, the state's emerald ash borer coordinator.

The discovery in Buena Vista County came as a surprise because of its location in northwestern Iowa, far removed from the widespread infestation in the southern and eastern regions of the state, he said.

The spread was likely due to the transport of emerald ash borer-infested firewood, Kintner said, which becomes more common with the start of camping season. The average person can't easily discern whether firewood is impacted, he said.

To prevent the beetle's spread, citizens should buy local firewood and avoid moving it outside the area, he said.

A federally enforced USDA quarantine prohibiting the transport of hardwood firewood and ash products outside of Iowa into non-quarantined states still is in effect, according to a state news release.

There are options for individuals who want to protect healthy ash trees, like insecticides, said Iowa State University Extension and Outreach Forester Jesse Randall. But people considering preventative treatment should have their trees inspected by a state expert to ensure they are good candidates, he said.

Additionally, some communities are opting to remove ash trees proactively, as trees weakened by beetles can become safety hazards, Kintner said.

Emerald ash borer, native to Asia, was first detected in the United States near Detroit in 2002. Randall said experts initially believed they could eliminate the threat but abandoned that hope long before the beetle was detected in Iowa in 2010.

Officials first found the beetle in Linn County in 2015 and Johnson County in 2016. Since Iowa trees weren't impacted until eight years after the first U.S. detection, state officials had time to educate and prepare citizens to deal with the destructive bug.

But despite this advance preparation, emerald ash borer continues to increase its range across the continent. Twenty-nine states and two Canadian provinces are battling infestations, according to the Emerald Ash Borer Information Network.

'It has pretty much covered the native range of ash trees,” Randall said.

Adult beetles are metallic green and 1/2-inch long. The larvae burrow through essential tree tissues beneath the bark, starving a tree and killing it in two to four years.

Anyone who suspects an infested tree in a county not known to have emerald ash borer is encouraged to contact the Iowa Emerald Ash Borer Team, which includes experts from the state agriculture department, Iowa Department of Natural Resources and Iowa State University Extension and Outreach.

To find a list of contact names and numbers, go to iowatreepests.com.

l Comments: (319) 368-8542; rilyn.eischens@thegazette.com