Planting a Forest for the Future

The wetland forests in the headwaters of the North Pikes Creek watershed, like other northern Wisconsin forests, are facing the dual challenges of a warming climate and an imminent infestation of an invasive insect – the emerald ash borer. The Friends of the North Pikes Creek Wetlands (Friends), a conservation organization and owner of property in the headwaters of North Pikes Creek, is proactively addressing these challenges to ensure that their forests remain healthy and continue to provide homes for the many wildlife species that depend on this wetland forest ecosystem.

Over a three-day weekend in May, fifty-three dedicated community volunteers gathered at Beaver Hollow to underplant 800 trees in the Friends’ black ash dominated wetland forest. Volunteers from several organizations – the Friends of the North Pikes Creek Wetlands, Superior Rivers Watershed Association, Trout Unlimited’s Great Lakes Program, and a Northland College Ecological Restoration class – came together to plant four tree varieties in the wetlands, in anticipation of the future loss of the black ash trees in this northern forest.

The emerald ash borer (EAB) is an invasive wood-boring beetle that kills 90% of the trees it infects. The larvae of the beetle bore into the vascular tissue under the tree’s bark, damaging its ability to transport moisture and nutrients from the soil to the leaves, resulting in the tree’s death. EAB was first identified by the WDNR in the local area in 2022.

The warming climate has accelerated the spread of this invasive insect. While a majority of the EAB larvae will die at temperatures of -30 degrees Fahrenheit, such temperatures are now rarely experienced in northern Wisconsin. Thus, far northern Wisconsin forests are not getting cold enough in the winter to slow or prevent the spread of the emerald ash borer.

Black ash trees are uniquely suited to growing in wetland forests. They function like giant straws and suck up water from the landscape – as much as 60 gallons per mature tree per day. If all the ash trees in the forest die from an EAB infestation, the wetlands will get wetter, and tree regeneration will be difficult, if not impossible.

The Friends are working proactively to prevent the loss of the forest canopy by underplanting their wetland forest before the ash trees are gone. Since American elm trees once grew in Northwest Wisconsin’s wetlands and drainages along with ash before they were killed by Dutch elm disease, the Friends are planting disease resistant varieties of elms in the wetlands. The group is also focusing on establishing alternative trees species that are expected to fare well in a warming climate.

This year, the Friends planted swamp white oak, bur oak, and hackberry trees that are native further south in Wisconsin. This planting mimics what will happen naturally as the climate warms. Trees normally migrate north in response to warmer temperatures, and the Friends are assisting that natural range migration.

The Friends’ forest underplanting project will continue for the next four years. Tree species planted in successive years will be based on the success of the previous years’ plantings. This years’ planting project was made possible by generous funding from the James E. Dutton Foundation, the C.D. Besadny Conservation Fund of the Natural Resources Foundation of Wisconsin, and the Fund for the Environment of the Duluth Superior Area Community Foundation.

As the project moves forward, the Friends will share what they have learned from these multiple plantings to assist other landowners with their forest management projects.

To learn more about the Friends of the North Pikes Creek Wetlands, please visit https://northpikescreek.org, or email inquiries to info@northpikescreek.org.

(Reprinted from “Bottom Line News and Views”, August 14, 2024.)