LINN COUNTY, Iowa - The Emerald Ash Borer now has another confirmed foothold in Iowa with a second infestation of the bugs discovered in an ash tree in Burlington. But forestry experts in east central Iowa aren't sure if a second infestation will change preparations for the pest in Linn County.
The tree-killing beetle was first discovered in Allamakee County in far northeastern Iowa in 2010. Biologists set traps and expected the pest to begin working its way westward into other parts of Iowa after finally crossing the Mississippi River. Other states in the Midwest saw infestations begin years ago. The beetle kills ash trees by burrowing under layers of the bark and killing the actively-growing parts of the tree.
Linn County remains at least 80 to 90 miles from the closest infected area to the northeast and now the southeast. But local foresters still expect the bug to threaten local ash trees before too many more years.
Dustin Hinrichs, field coordinator for Trees Forever, said there was some surprise the borer showed up for the second confirmed time 180 miles to the south in Burlington rather than somewhere closer to the original outbreak in Allamakee County. Hinrichs said those in Linn County who shrugged off the original concern about the borer after several years with no sightings may be thinking differently now.
"Now that we have two potential avenues for the insect to start
spreading, people should be a little more interested and start actively thinking about what they would do on their property," Hinrichs said.
In Marion, the city is setting aside funding to pay for removing ash trees as the borer works its way into the area. But Mike Carolan, Marion Parks Director, said aside from a few stressed ash trees, the city has not started to proactively remove large numbers of ash trees.
By contrast, Cedar Rapids began a policy more than two years ago of removing 400 to 500 susceptible ash trees every winter before the borer has a chance to strike. One Cedar Rapids manager says the city will likely continue that early removal and replacement policy but will probably not speed it up with the discovery of a second infestation.