Black ash is an important component of northern hardwood forested wetlands, an ecological community throughout the Great Lakes region that occurs in three major landforms: headwater wetlands, which are small isolated wetlands surrounded by forested uplands, large wetland complexes that cover many acres, and drainways along intermittent and first-order streams. . The ash themselves have cultural significance to native communities and provide an economic resource to the region through timber. The wetlands that the ash are a part of help protect the water quality, regulate water quantity, and act as a sink for carbon. These wetlands are threatened by the spread of the invasive emerald ash borer (EAB), which is beginning to reach the areas where black ash is most prevalent on the landscape. The loss of ash in these wetlands will lead to ecological changes, many of of which will push the systems away from forested wetland cover.

Contiguous extent of Emerald Ash Borer and Importance Value of black ash throughout its range

The goal of this project is to determine the impact of EAB on black ash wetlands, but in order to say we’ve met that objective we have to break it down into many smaller directly answerable questions. These are wetlands, so the first obvious question is what will happen to the water levels when the ash succumbs to EAB? And what is the main source of water for these wetlands? This leads to the next question, if the water levels do change what will that mean for retaining a forest wetland? Will natural regeneration be enough to replace the lost ash or should wetlands be planted to promote species transition? If they are planted what species should be planted? What about the canopy trees that aren’t ash? And the understory? The herbaceous community? How will the increased light affect them. On top of all the things we can see we know that there will be more subtle changes that could shape the future of these wetlands, for instance how will nitrogen and carbon move through these altered systems? After these questions are answered it still leaves another big question, what does this mean at a bigger scale? Are these changes confined to black ash wetlands or will we see some of these changes transmitted down first-order streams as changes in water quality and stream discharge?