By Paul Cigan, DNR Forest Health Specialist
Paul.Cigan@wisconsin.gov or 715-416-4920
Emerald ash borer (EAB) has been discovered in Bayfield County for the first time in both the city of Bayfield and Bayview township to the south. This marks the 63rd out of Wisconsin’s 72 counties to have an EAB discovery since its initial detection in 2008.

Figure 1: First known infested ash tree in Bayfield County with characteristic woodpecker damage (i.e., flecking).
Photo: Wisconsin DNR
Several white ash trees (Fig 1.) were observed in and around a roadside park in the city of Bayfield, and larval specimens were subsequently lab-confirmed. In Bayview, a black ash swamp had several infested black ash (Fig 2).
After introduction, EAB populations remain low for at least several years as most larvae in newly infested, healthy ash require two years to complete their life cycle. The abundance of healthy ash at each site suggests EAB populations have remained low since their introduction at least three years ago. However, EAB will kill ash more quickly as beetle numbers mount and more larvae transform from egg to adult in a single year. Unfortunately, many ash in the area are expected to die within four to seven years based on detection-to-impact timeframes observed from the Superior and Duluth area and research conducted in midwestern states. Continue reading “Emerald Ash Borer Found In Bayfield County”



Now available for download are the
When I returned to my hometown neighborhood in northeast Ohio this past August, I was delighted to rekindle my friendship with so many trees that I have known most of my life. There are, of course, the Norway maples and crabapples and blue spruces found in maintained spaces throughout eastern America. One also finds a fair number of sugar maples and Ohio buckeyes. But despite apparently living in a democracy, red oak is king of my neighborhood.


Do you have a tree inventory but have had a hard time keeping it current, or you’re interested in inventorying some trees of your own? The Wisconsin Department of Natural Resources (DNR) is funding several accounts for communities or organizations to edit data within the