Dakota County prepares for spread of emerald ash borer

Dakota County is seeking advice on a new relationship – one that it wants no part of.

Unfortunately, it's with a pest that is in it for the long haul.

State workers found the dreaded emerald ash borer last month in Lebanon Hills Regional Park, located in Apple Valley and Eagan. It was the first sighting of the tree-destroying beetles in Dakota County, and officials said they are here to stay.

"It's definitely not something we can eradicate. We can only manage it," said Jessica Schaum, Apple Valley's natural resources coordinator. "It's a long-term relationship now that it's here."

Officials from the county, cities and state Department of Agriculture met recently to form a plan to deal with the bugs' impact. Officials are also talking with other affected counties, like Hennepin, about bug management.

Residents and government staff have a few months to prepare for the spread of the infestation. The bugs will not begin to fly from tree to tree until spring.

In the meantime, residents need to think about the trees on their property, Schaum said. If they have an ash tree that they love, she said, they should treat it with insecticide. Otherwise, people need to plan for the eventual removal of the ash and perhaps plant a different species of tree.

Cities around the metro have long anticipated that they would be hit by the ash borer.

Gregg Hove, a forester in Eagan, said the city has been checking trees since the insects were first found in Minnesota in 2009.

"This just heightened the alert a little bit," he said

Last year's freezing winter killed 60 to 70 percent of the emerald ash borers, University of Minnesota Entomology Professor Jeff Hahn said. The beetles start to die off at temperatures below -20 degrees, he said.

So while this winter may feel cold, Hahn said it will not keep ash borers at bay.

But it does make them easier to locate.

In the winter, when the trees are barren, it is easy to spot the insects, Schaum said. Woodpeckers find the green beetles before humans do.

So government staff can head to the woods with binoculars and hunt for holes in trees, she said. If there are tunnels in the wood, it's too late.

"Your tree is probably riddled with them," Schaum said.

Jessie Van Berkel • 952-746-3280