The tree-killing emerald ash borer has been confirmed in a residential tree in Eddyville and in trees in the public right-of-way in Waverly, state officials reported Wednesday.
Those infestations, confirmed Feb. 12, are the seventh and eighth documented in Iowa.
The occurrence is becoming so commonplace that state officials announced it in a press release rather than in the telephone news conferences called to disclose earlier discoveries.
“I think we will continue to find it at a more rapid pace,” State Forester Paul Tauke said Wednesday.
“We have not found it yet in northwest Iowa, but in the rest of the state the dots are going to start filling in” between the documented infestations,” Tauke said.
Until last year only one Iowa infestation had been confirmed — in the state’s far northeast corner in 2010.
Four were confirmed last year — in Des Moines, Jefferson, Cedar and Union counties – and already this year infestations have been confirmed in Black Hawk, Wapello and Bremer counties.
The infestation in Eddyville was found by a citizen who reported suspect ash trees to a Department of Natural Resources regional forester. In Waverly an arborist hired by the city to do a tree inventory discovered larvae in declining ash trees along two city streets. In both cases federal officials positively identified the larvae as EAB.
“I wouldn’t be surprised if more infestations are found in Iowa before we shake the final snowfall from our boots and trees leaf out this spring,” said Robin Pruisner, state entomologist with the Iowa Department of Agriculture and Land Stewardship
When ash trees are leafless in the winter, the presence of ash borers is most often detected by flecking and drilling by woodpeckers in the trunk and upper branches, Prusiner said.
When the trees begin to leaf out this spring, officials will look for thinned canopies and green shoots sprouting near the base of the trunk, she said.
In most cases, Tauke said, the infestations have been present for at least four years. “It’s not that it is spreading rapidly. We’re finding it because more people know what to look for and more people are looking for it,” he said.
A statewide quarantine restricting the movement of hardwood firewood, ash logs, wood chips and ash tree nursery stock out of Iowa into non-quarantined areas of other states was issued on Feb. 4.
Officials caution Iowans not to transport firewood across county or state lines, since the movement of firewood throughout Iowa or to other states poses the greatest threat to quickly spread EAB even further.
Iowa has an estimated 52 million rural ash trees and 3.1 million ash trees in urban areas.