Helicopter tree removal to help control oak wilt on Belle Isle; park access limited during removal

Contact: Heidi Frei, 517-284-6133
Agency: Natural Resources

March 9, 2017

example of oak wiltThe Michigan Department of Natural Resources, in conjunction with the Belle Isle Conservancy, has announced a helicopter will be used to transport felled logs out of a sensitive habitat area at Belle Isle Park. The work, expected to take place the week of March 12, is part of a four-phase management effort to control oak wilt and protect a rare flatwoods forest at the park. 

Oak wilt is a fungus that can spread from tree to tree through underground root connections, or grafts. It also can spread when diseased trees develop fungal mats. During the growing season, the sweet-smelling fungus attracts sap-feeding beetles that carry fungal spores to other wounded trees in much the same way that bees transport pollen.

In fall 2016, a survey was conducted that revealed that oak wilt may have killed as many as 112 trees in a rare flatwoods forest near the center of the island. The DNR quickly drafted a plan to contain and manage the disease in order to protect the historic forest and some of the state’s last remaining Shumard’s oaks. It was determined that oak wilt may have been present for many years.

In late December, crews completed the first of four management phases, which involved severing the roots between infected and healthy trees using a plow outfitted with a special cutting blade. The second phase, which began this week, will include cutting down and removing dead trees before fungal mats develop and allow the disease to spread. To prevent damage caused by heavy equipment, the helicopter will be used to transport felled logs to a staging area in the island for processing. This technique was determined to have the least impact to the surrounding flatwoods forest. 

Temporary closure of nature center, yacht club, some roads

The Belle Isle Conservancy has contracted with Vertical Flight Technologies for the helicopter service, estimated to take two days. During this time, all access to the forested end of the island, east of Vista Lane, will be closed. The closure will include roads, hiking trails, pathways and facilities and will affect day-use activities. The closure will be marked for visitors.

This project was funded in part with $194,000 from the Michigan Invasive Species Grant Program, through the state departments of Natural Resources, Environmental Quality, and Agriculture and Rural Development.

"When oak wilt was discovered on Belle Isle, DNR staff developed a plan for effective management and control of this damaging tree disease," said Heidi Frei, a natural resource steward for the DNR. "We will continue working with our partners to contain and eliminate this deadly tree fungus. Preserving Belle Isle's beautiful forest areas is a top priority, both for the natural landscapes of the island and for the visitors who enjoy them."

The DNR hosted two public informational meetings Feb. 23 at Belle Isle to share information on the department's oak wilt containment and tree protection efforts. 

Future control efforts

After the diseased wood has been removed from the island, two more management phases are planned. The third phase will take place this spring and will involve approximately 150 trees in or near areas of known oak wilt, including many of the island’s Shumard’s oaks, being injected with a fungistat that may prevent infection. The final phase will begin in late August and will include monitoring infected trees throughout the year. Early detection of future infestations will be critical for successful control.

What can you do?

It is likely that the oak wilt fungus came to Belle Isle on infected material like firewood. The DNR reminds travelers and state park visitors to leave wood at home and to instead buy and burn firewood at or near your destination – don’t bring it back home.

Information about oak wilt management in Belle Isle Park periodically will be updated on the DNR website at www.michigan.gov/protectmipark. For more information, contact Heidi Frei at 517-284-6133 or freih@michigan.gov.

The Michigan Department of Natural Resources is committed to the conservation, protection, management, use and enjoyment of the state’s natural and cultural resources for current and future generations. For more information, go to www.michigan.gov/dnr.

An accompanying photo is available below for download. It provides a close-up view of an oak wilt-infected tree in Michigan's northern Lower Peninsula and shows the type of damage some of the trees on Belle Isle are experiencing.