Beetle battle continues

By Kurt Hauglie

HOUGHTON – It’s likely the emerald ash borer beetle has been in the Calumet area since 2002, and since then it’s spread to southern Keweenaw County and at least to the area around the city of Houghton.

Since the ash tree-killing insect has continued to spread locally and in much of the Upper Peninsula, the Michigan Department of Agriculture and Rural Development has expanded a quarantine against moving wood to all of Alger, Chippewa, Delta, Houghton, Keweenaw, Luce, Mackinac and Schoolcraft counties. Only logs and timber certified as insect free can be moved out of those counties.

Andrew Storer, associate dean in the Michigan Technological University School of Forestry and Environmental Science, said previously the quarantine against moving wood was only in parts of counties where the EAB was known to be, but the spread of the insect is considered an infestation, which means greater efforts against its spread have to be made.

“We know it’s already on the south side of the (Portage Lake Lift Bridge),” he said.

The EAB has been found on the Michigan Technological University trails, on the Canal Road and even in trees around the parking lot of the U.J. Noblet Forestry Building where Storer has his office. To the north, it’s been found in southern Keweenaw County.

The presence of the emerald ash borer was first discovered in the Detroit area in 2002. It’s thought the Asian native was brought in wooden crates on ocean-going freighters, which docked in Detroit.

In the Upper Peninsula, the EAB was first discovered in 2005 at Brimley State Park near Sault Ste. Marie.

Much of the spread of the insect is due to the movement of firewood.

Since the EAB arrived in the United States, Storer said in Michigan and surrounding states, about 50 million ash trees have been killed by the beetle, which lays its eggs under the bark of the tree. The larvae of the insect eats the wood of the tree, causing its eventual death.

Storer said last summer crews with the Slow Ash Mortality project were examining the purple traps covered with an adhesive to catch the beetles placed in woodlots relatively far from roads.

“We’ve been looking at distances from the roads for trapping success,” he said.

The EAB prefers sunny areas, and many have been found in the open areas next to roads, which means the more deeply-placed traps may not work any better for catching the beetle.

“We suspect it will be no more effective than (those placed) next to the roads,” he said.

This coming summer, Storer said crews will be looking at the traps placed far from roads. They will also examine the effectiveness of the releases of three types of parasitic wasps, which lay their own eggs either on the EAB eggs or the larvae.

“We’d like to get a feel for the percentage of emerald ash borer being affected by this,” he said of the biological control project.

Crews will also be looking at long-term control plots to determine the effectiveness of various efforts to control the spread of the EAB.

In the Calumet area, Storer said the mortality rate for ash trees is 90 percent, and he expects that to continue.

“We’re going to have a lot of dead trees next summer,” he said.

Funding for the SLAM project comes from the United States Department of Agriculture Forest Service. It’s uncertain if Storer will get funded each year.

“Funding is not as easy to get as it was,” he said. “It’s up in the air as to what’s going to come through at this point.”