Minnesota Tree-Planting Push Aims to Buffer Insect Invasion

The declining Golden-winged Warbler is among many songbirds that could be affected in the Great Lakes region by advancing Emerald Ash Borer infestations. Photo by Lynda Goff

The declining Golden-winged Warbler is among many songbirds that could be affected in the Great Lakes region by advancing Emerald Ash Borer infestations. Photo by Lynda Goff

In spring 2020, American Bird Conservancy (ABC), along with public and tribal lands partners within the Lake Superior Basin in Minnesota, launched a project to conduct enrichment planting in Black-Ash-dominated forest stands to increase habitat resilience for the anticipated impact of the region's advancing Emerald Ash Borer (EAB) infestation.

Black Ash forests, a common forest type in the Great Lakes region, provide breeding and migratory stopover habitat for a wide range of native birds, such as the Golden-winged Warbler, Ovenbird, Red-eyed Vireo, Veery, Northern Waterthrush, and Northern Parula. Minnesota's Black Ash forests also provide nesting locations for Great Blue Herons, and edge habitat used by foraging Ruffed Grouse. These forests are vulnerable to impacts from the Emerald Ash Borer (EAB), an introduced invasive insect that destroys ash trees.

“Minnesota has about 1 million acres of pure Black Ash forests. These trees grow in nearly pure stands with very little presence of other tree species,” says Kevin Sheppard, ABC's Golden-winged Warbler Private Lands Coordinator. “ABC is in a unique position to help partners plan projects, secure funding, and maintain these unique forest types due to our professional forestry presence in the region. This is slightly experimental work and our hope is that we can build on this opportunity and expand the project in the future.”

Across the landscape, wet, lowland Black Ash forests play an important role in regulating groundwater. Black Ash trees are uniquely suited to moist conditions and retain excess water. It is expected that EAB will be devastating to these forests, particularly in northern Minnesota and Wisconsin, where Black Ash are common.

This infestation is most likely inevitable, as EAB has spread widely throughout the region and is making its way north. When it hits, the anticipated die-off of ash trees will likely result in conversion of these sites to wet lake-sedge and shrubby swamps, spelling the end of forest cover in these locations.

To prevent this, ABC has initiated experimental inter-planting of replacement tree species among Black Ash stands. ABC will treat 100 acres on five to six sites, planting approximately 400-1,000 trees per acre, depending upon the plant community composition at each site. ABC will plant hardwood trees that are scientifically shown to produce the best survival rates, with the aim of increasing habitat resilience to EAB invasion. These will be trees that, like the Black Ash, can survive wet conditions, but they will be resistant to EAB impacts. By planting young trees now, ABC and partners aim to preserve the value of these forests for birds and other wildlife.

This work is based on research done on the Chippewa National Forest, where foresters have installed plots that simulate EAB infestation conditions.

This project is funded by a Great Lakes Restoration Initiative grant through the U.S. Department of Agriculture, Forest Service, and the U.S. Environmental Protection Agency (EPA). 

 Our efforts are also benefiting from the partnership of the Minnesota Department of Natural Resources, the Carlton County (MN) Land Department, and the Fond du Lac Band of Lake Superior Chippewa. ABC is grateful to all of our funders and partners, who are helping make these bird conservation results possible.


Media Contact: Jordan Rutter, Director of Public Relations, 202-888-7472 | jerutter@abcbirds.org | @JERutter
Expert Contact: Kevin Sheppard, Golden-winged Warbler Private Lands Coordinator | ksheppard@abcbirds.org

American Bird Conservancy is a nonprofit organization dedicated to conserving birds and their habitats throughout the Americas. With an emphasis on achieving results and working in partnership, we take on the greatest problems facing birds today, innovating and building on rapid advancements in science to halt extinctions, protect habitats, eliminate threats, and build capacity for bird conservation. Find us on abcbirds.org, Facebook, Instagram, and Twitter (@ABCbirds).