Minn., Wis. impose quarantine to fight spread of ash borer

Emerald ash borer
The emerald ash borer is responsible for millions of dollars of damage to ash trees in Michigan, and it's spreading to other states. The adult borer is a metallic, coppery-green color and one-third to one-half inch long.
Photo by David Cappaert of Michigan State University, courtesy of www.forestryimages.org

The Minnesota Department of Agriculture is imposing a quarantine on wood from ash trees in southeastern Minnesota, to try to control the spread of the emerald ash borer.

Officials now think that emerald ash borers have been in trees on the Wisconsin bank of the Mississippi River for as long as 10 years.

The Minnesota Department of Agriculture's director of Plant Protection, Geir Friisoe, told lawmakers that the beetles move about two miles per year.

Damage from ash borer
Emerald ash borers create "galleries" under the bark of ash trees, and the damage can eventually kill the tree.
Photo courtesy of Michigan Department of Agriculture

"We believe emerald ash borer is in Minnesota. We have not found it," said Friisoe. "The prudent thing to do is to make sure ... no ash wood moves out of Houston County to protect the rest of the state. We think that's the best course of action for Minnesota."

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Wisconsin agriculture officials have also imposed a quarantine on firewood and other wood products in the southwestern part of the state in hopes of containing the insect.

Agency officials said Wednesday they have banned the movement of firewood, ash timber, ash nursery stock, mulch and manufactured ash products out of Vernon and Crawford counties.

Ash borer larva sample
The Minnesota Department of Agriculture brought samples of the Emerald Ash Border larve and beetle to show lawmakers at the Capitol. Ag department officials believe these insects have likely established a presence in southeastern Minnesota and declared a quarntine on ash wood in Houston County, along the Mississippi River.
MPR Photo/Tim Nelson

Officials say there is little else they can do to stop the bugs, which hatch as larve under ash tree bark and feed on the trees. Infestations have wiped out large stands of ash trees in Michigan and Ohio.

(The Associated Press contributed to this report)