Beech Tree Disease Spreads in EUP
By Paul Gingras

The last medium-sized beech tree in the South Manistique Lake State Forest Campground came crashing down at approximately 2 p.m. Monday, May 22, cut by Department of Natural Resources (DNR) foresters before they fell on their own, weakened by Beech Bark Disease (BBD).

The disease threatens to destroy 50 to 80 percent of the beech trees in Michigan, especially those in concentrated stands. The destruction begins with the infestation of American Beech Trees by a tiny insect called "beech scale," which enters the bark and feeds on sap. The resulting wounds allow a fungus to kill woody tissue. Over the course of several years, infected trees become fragile and break, an unfortunate phenomenon called "beech snap," which often occurs during wind storms.

To avoid beech snap at South Manistique Campground, state foresters worked 10 straight days to remove the majority of large and mediumsized beeches from the area. Their efforts allowed the popular camp site to reopen Friday morning, May 26, just in time for Memorial Day weekend.

Not every beech was removed. Young trees with smooth bark may be resistant to the disease, so saplings were left behind to regenerate the stand. Even some larger beech trees appear to be immune to BBD, according to Michigan State University (MSU) Extension. They are found growing, free of scale or fungal infection, in the midst of forests heavily infested with BBD.

But, for the most part, mature trees are particularly vulnerable, because their rough and damaged bark provides access to scale.

Homeowners with American Beech on their land should watch out for potential beech snap. Beech scale infestations are notable because the insects secrete a white, woolly substance on the tree bark.

Because the disease has appeared at other campgrounds, foresters believe it is being spread, in part, by campers transporting beech logs for use as firewood.

"The mobile life stage of the beech scale, known as crawlers, is in the fall," said Robert Heyd. "They are readily dispersed by birds and strong winds. Moving recently harvested wood from infested areas risks spreading beech scale to new areas at greaterthan expected rates."

Beech Bark Disease appeared in Michigan in 2000 and has since spread throughout most of the Eastern Upper Peninsula, which is at the western edge of its range, said Pat Hallfrisch, a state forest unit manager for the DNR,

The loss of Michigan's older American Beech population is likely to have a negative effect on some forms of wildlife and a positive effect on others.

Once beeches reach 40 years of age, they begin to produce large quantities of nuts that are eaten by more than 40 species of birds and mammals, including black bears, gray squirrels, chipmunks, turkeys, and deer.

On the other hand, the dead and dying trees create new habitats for invertebrates and nesting cavities for birds.

An example of such a beech tree is left at the campground because a pair of pileated woodpeckers is nesting in it. When their young are gone, that tree, too, will come down.

The disease originated in Europe and appeared in Nova Scotia in 1890 on ornamental beech trees. During the 1930s, beech scale and its associated fungus spread throughout eastern Canada and into areas of Via Firewood

Maine. By 1960, New England and New York had been affected. The disease continued to spread through Quebec, northern Pennsylvania, and northeastern West Virginia. Beech scale also persists in isolated areas of Ontario, Ohio, Tennessee, North Carolina, and Virginia, according to MSU Extension.

The disease is relatively new in Michigan, so many do not yet realize the implications of having it in the region, Mr. Heyd said. Education efforts are ongoing.

In 2004, he said, 2,000 acres of the Upper Peninsula affected by BBD were replanted with oak, hemlock, red pine, and white pine. The effort was assisted by the Wildlife Divisions Landowner Incentive Program.