By Hannah Coyle

Goodhue County remains under an emerald ash borer quarantine more than a year after the tree-killing insect was identified in Red Wing in March 2017. Experts advise early detection and treatment measures to combat infestations.

"The biggest thing is being able to determine whether you have an ash tree," said Ryan Brick of Maier Tree & Lawn. "Preventative measures are the best measures."

Signs of emerald ash borer infestation in an ash tree include D-shaped holes the size of the tip of a pen, extensive woodpecker damage and splitting bark.

The city of Red Wing is in an area labeled generally infested, according to a Minnesota Department of Agriculture map. Colvill Park, Memorial Park and Barn Bluff have all been affected by the destructive beetle.

The quarantine for firewood and ash wood products was designed to slow the spread of emerald ash borer by reducing the flow of plant products from and throughout the Goodhue County area. The agriculture department advises purchasing only wood that is MDA certified as heat-treated to ensure it is free of pests.

Emerald ash borer was first identified in the U.S in 2002. Spreading through 33 states and three Canadian provinces, the insect has been spotted throughout much of southeastern Minnesota. The metallic green beetle likely traveled from Asia on cargo ships and airplanes.

Minnesota is estimated to have 1 billion ash trees.

For more information on emerald ash borer and treatment options, visit or the city of Red Wing's website at


Hannah Coyle, a 2018 Red Wing High School graduate, is a summer intern at the Red Wing Republican Eagle.