TRAVERSE CITY — Once a beech tree’s smooth gray bark is marked by minuscule, cotton-like scale insects, it’s likely marked for death.
The insects gnaw away at the bark and open it to Beech Bark Disease by making it vulnerable to a certain kind of fungus that forms a canker, or wound, in the tree.
The National Park Service hopes to get a step ahead of widespread infection and create both a more aggressive tree take-down policy and restoration policy at northern Michigan’s signature national park.
“We want to make sure we keep the public safe and we have tools in our toolbox to take the actions we need to take quickly and decisively,” said Kevin Skerl, the Chief of Natural Resources at Sleeping Bear Dunes National Lakeshore.
The lakeshore’s beeches are not alone. Its ash trees are infected by the emerald ash borer, a beetle that chomps on the sensitive layer underneath the tree’s bark, disrupts the flow of nutrients in the tree, and eventually kills it. And the park’s oak trees, while currently healthy, could soon fall victim to oak wilt, a fungal disease that’s been reported in Benzie County.
The National Park Service seeks public input on a new Hazard Tree Management Plan. Park neighbors and concerned citizens can submit their suggestions and input online until Feb. 15.
Beech and ash trees are both integral parts of the area’s forests.
“They’re high canopy trees that a lot of wildlife depend on,” said NPS biologist Ken Hiser, who came to Sleeping Bear Dunes six months ago to work on the new plan. “(The diseases) are going to change things in ways you might not notice, but there’s a big change.”
The new plan is still in its exploratory phase and will need to pass an environmental assessment and several other hurdles before it can be implemented. Skerl said the plan would prioritize only certain areas for removal, such as campgrounds and heavily trafficked trails.
Emerald ash borer is already rampant in the park, but there only are early signs of beech bark disease, and no reports yet of oak wilt.
Still, Skerl expects it’s only a matter of time until the disease reaches the National Park. He said it’s important to be able to take down infected trees before they’re completely dead.
“When a beech tree is being attacked by beech bark disease, it often becomes dangerous to cut down the tree at the time it’s exhibiting symptoms because it’s hollowed out from the inside,” Skerl said.
The NPS has already taken some steps to try to save the park’s trees, Hiser said.
About 300 ash trees have been injected with a pesticide to stop the deadly beetle. Park Service employees also released a certain type of wasp that’s harmless to humans but attacks emerald ash borer larvae.
Tree diseases aren’t new to the area, although all are non-native species, said Bill Cook, a Michigan State University Extension forester and wildlife biologist.
“We’ve been dealing with fatal exotic diseases and insects in forest systems for over a century, but the number of them occurring in North America has begun to accelerate as our trade with east Asia accelerates,” Cook said. “One hundred years ago, most of our pests came from Europe, but now eastern Asia is the source of most infestations.”
Diseases like oak wilt and Beech Bark Disease are older, while the emerald ash borer was first identified in 2002, Cook said.
“Emerald ash borer and beech bark disease will eliminate and suppress most of our ash and beech resources,” Cook said.