The Minnesota Department of Agriculture (MDA) has confirmed emerald ash borer (EAB) in Brown County.

This is the 21st county in the state with EAB.

A tree care professional contacted the MDA after they noticed an ash tree with EAB symptoms at a private residence in the City of New Ulm. MDA staff were able to find live EAB larvae and collect a sample for federal identification.

“This is the third new county find in the past two months, with an EAB discovery in Nobles County the end of July and Steele County two weeks ago,” said Mark Abrahamson, director of MDA’s plant protection division. “However, these finds are not a coincidence. This is one of the best times of year to notice dying and stressed ash trees. Look for signs like dieback from the top of the tree, new shoots or growth at the lower trunk, bark splitting and extensive woodpecker damage, and report these symptoms to the MDA.”

Because this is the first time EAB has been identified in Brown County, the Minnesota Department of Agriculture will be enacting an emergency quarantine to limit the movement of firewood and ash material out of the county. This will reduce the risk of further spreading the tree-killing insect. Residents of Brown County are also invited to an open house being held Oct. 8. 

The open house will address the discovery of emerald ash borer in the county. Those attending the open house will have an opportunity to learn more about EAB and local options to deal with the insect and hear how residents can limit the spread of the bug. Experts will be available to answer questions. The open house is being held at the Brown County Law Enforcement Center in New Ulm from 6-8 p.m.

The public will also have an opportunity to provide input on the proposal to add Brown County to the state formal quarantine. The MDA will take comments on the proposed formal quarantine through Nov. 7, 2019, and proposes to adopt the quarantine Nov. 14, 2019. The quarantine limits the movement of ash trees and limbs and hardwood firewood out of the county.

The proposed quarantine language can be found at Comments can be made at the open house or by contacting Kimberly Thielen Cremers, Minnesota Department of Agriculture, 625 Robert Street North, St. Paul, MN 55155, via e-mail at or by FAX to (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 and is now found in 35 states.

EAB will have a major impact on Minnesota. The state has approximately one billion ash trees, the most of any state in the nation.

– Photo courtesy of the Minnesota Department of Agriculture Web site