February 4, 2021

The Minnesota Department of Agriculture (MDA) has confirmed emerald ash borer (EAB) in Cottonwood County in southern Minnesota. This is the 26th county in the state with EAB.

MDA staff recently conducted a visual survey south of the city of Comfrey where the insect had been found last summer. A grouping of trees south of the county line in Selma Township had typical woodpecker damage indicating the presence of EAB. MDA staff were able to find live EAB larvae and collect samples for federal identification.

An ash tree with EAB may show several signs of infestation, including woodpecker holes and bark cracks. Woodpeckers like to feed on EAB larvae and woodpecker holes may indicate the presence of emerald ash borer. Also, EAB larvae tunneling under the bark can cause the bark to split open, revealing the larval galleries underneath.

Because this is the first time EAB has been identified in Cottonwood County, the Minnesota Department of Agriculture is enacting an emergency quarantine to limit the movement of firewood and ash material out of the county. The MDA issues quarantines for all counties known to have EAB to reduce the risk of further spreading the tree-killing insect.

Two virtual open houses for residents and tree care professionals in the county will be held on Wednesday, February 24. Experts from the MDA will give a brief presentation followed by a question-and-answer session.

Emerald Ash Borer Virtual Informational Meetings
Wednesday, February 24
10-11 a.m. or 6:30-7:30 p.m.
Register on the MDA website.

The public will also have an opportunity to provide input on the proposal to add Cottonwood County to the state formal quarantine. The MDA is taking comments on the proposed formal quarantine now through March 12 and recommends adopting the quarantine on March 15. The quarantine limits the movement of ash trees and limbs and hardwood firewood out of the county. The proposed quarantine language can be found on the MDA website.

Comments can be made during the virtual meeting or by contacting:

Kimberly Thielen Cremers
Minnesota Department of Agriculture
625 Robert Street North
St. Paul, MN 55155
Fax: 651-201-6108

Emerald ash borer larvae kill ash trees by tunneling under the bark and feeding on the part of the tree that moves nutrients up and down the trunk. The invasive insect was first discovered in Minnesota in 2009.

There is more EAB information on the MDA website.

Media Contact
Allen Sommerfeld, MDA Communications