Oak wilt, a dreaded fungal disease that wipes out red oaks and can devastate forest systems, has been discovered at the planned Turtle Cove Nature Preserve on Arbutus Lake. The Grand Traverse Regional Land Conservancy (GTRLC) aims to buy the 120-acre property at the end of the year and is working to remove nearly 400 trees in the coming weeks – a move staff say is “heartbreaking” but necessary to stop the disease from spreading.

GTRLC has nearly reached its fundraising goal of $2,473,007 to buy the planned preserve property from owners Casey and Dana Cowell. The conservancy has raised $2,002,772, or 81 percent of the needed funds – and hopes to raise the remaining $470,235 by December. The Turtle Cove Nature Preserve along Arbutus Lake will offer three-quarters of a mile of undeveloped water frontage, emergent marsh and bog habitats, mesic forest with open field, and habitat for nesting eagles, fish, reptiles, amphibians, and other species. A new parking area and two-mile scenic trail loop is planned for the property, which is neighbored by Pines Park and state land. With undeveloped shoreline on the decline, acquiring Turtle Cove “presents a relatively rare chance to safeguard unspoiled habitat,” according to GTRLC.

Unfortunately, the conservancy will first have to address a serious oak wilt infestation recently discovered on the property. While inventorying the site, GTRLC Land Stewardship Specialist Stephen Lagerquist says a conservancy botanist “had her heart ripped out of her chest because there was so much oak wilt on the property.” Oak wilt, which moves slowly on its own through root systems and can also travel by infected firewood or when spores are carried by insects from an infected tree to a freshly pruned or injured tree, kills healthy red oaks. “Once a red oak becomes infected with the oak wilt fungus, the tree will die, and there is no treatment to save the infected tree,” according to the Michigan Invasive Species Program.

Lagerquist notes that red oaks have root systems as big as their canopies and will root graft together, sharing water and nutrients. That also means they’ll share diseases like oak wilt. “A tree typically will show signs of the fungus by dropping leaves, then it browns up and dies off the next year,” Lagerquist says. “The tree will produce a spore pad that insects can take. That’s why we have to take out so many trees. It’s just not the trees that are already showing signs of infection at Turtle Cove, but all the trees within a certain distance of the infected trees, because they likely already have the fungus.” The Michigan Invasive Species Program highlights this risk, noting that if not addressed, “oak wilt will continue to spread, killing all red oaks in a neighborhood or a forest.”

That requires GTRLC taking the drastic step of removing up to 400 red oaks from Turtle Cove, with the permission and cooperation of the Cowells. “They have been great to work with and are proactively letting us do this on our potential property,” Lagerquist says. “We don’t own the property yet, but we’re in there doing management.” GTRLC is working with a tree expert to calculate the necessary boundary lines around the infected trees, cut trenches to separate and protect the root sytems of the remaining trees, and remove the flagged trees in the coming weeks. Trees already showing signs of infestation must be chipped up and destroyed so the oak wilt can’t spread elsewhere. Those being removed as a precaution because of root grafting can be repurposed as timber, helping offset project costs. With that offset included, Lagerquist estimates the total undertaking will cost approximately $20,000.

Lagerquist says the tree removal is “heartbreaking,” acknowledging it’s going to have an impact on the preserve. But he points to a few potential silver linings. First, if GTRLC hadn’t been actively working to acquire the property, Lagerquist says he’s “not sure anybody would have noticed the oak wilt. It could have been a lot more devastating. We could have lost all of the trees there.”

Second, forest systems have a knack for adapting to impactful events. “The bright side is that taking out that many trees opens up the understory for ground species to pop up,” Lagerquist says. “It changes the habitat.” When a devastating wind storm ripped through northern Michigan in 2016, it took down numerous trees at Maple Bay, Lagerquist notes. Soon after, “young juvenile species exploded with understory growth. Opening the canopy changes the ecology, because of all the young species that come in.” Accordingly, Lagerquist says that while removing hundreds of trees is a “tragic loss, it’s not a deal killer for us protecting the property. My guess is it’ll bounce back quickly. It’ll look different, but it will vegetate out quickly. It’ll just be a lot of juvenile species.”

A final silver lining: The containment approach being deployed by GTRLC has a 98 percent effective rate, Lagerquist says. However, the infestation is a reminder of the broader danger that oak wilt – which can weaken white oaks in addition to killing red oaks – continues to pose to Michigan trees. “We will always have to monitor that property now,” Lagerquist says. “Unfortunately, oak wilt has been bad in northern Michigan the last several years.”

The Michigan Invasive Species Program advises homeowners to know the signs of oak wilt infestation – trees suddenly wilting from the top down and rapidly dropping leaves in the summer is a dead giveaway – and to report the disease using this interactive map and contacting the DNR at DNR-FRD-Forest-Health@michigan.gov or 517-930-4294. Never prune oak trees during the growing season (between April 15 and July 15) and don’t move firewood from one location to another, as oak wilt is spread by moving infected wood.

Pictured: Top right, the planned Turtle Cove Nature Preserve (photo credit: Noah Jurik); bottom right and left, leaves and tree infected with oak wilt (photo credit: Monique Sakalidis/MSU).