Saving the ash trees


After killing millions of ash trees in five U.S. states and in parts of Canada since its first discovery in 2002 , the emerald ash borer has come to Minnesota. The Minnesota Department of Agriculture announced Monday that the beetle has infected 59 ash trees in St. Paul.

Now experts at the University of Minnesota are working to understand the emergence of the emerald ash borer in hopes to protect the some-1,400 ash trees on campus.

To do so, many have become First Detectors — or ash borer inspectors — through a series of training workshops .

The First Detector Program is part of the Minnesota Department of Agriculture , the Minnesota Department of Natural Resources and the University of Minnesota Extension , University entomologist Jeff Hahn said.

“When people think they may have the emerald ash borer, we can refer those people to the First Detectors and they can help them go through a series of questions to help determine whether they have it or not,” Hahn, who studies insects, said.

Dan Miller , integrated pest management specialist at the University-owned Landscape Minnesota Arboretum in Chaska, is a trained First Detector. He recently was sent out to check on a possibly infected tree.

“We went out on a call and we found out it was not the emerald ash borer, it was most likely one called the redheaded ash borer, which is a native borer,” he said. “That one was very close to the arboretum; it was only three miles away, so we were quite concerned.”

The arboretum has about 1,000 acres of trees, with about 130 ash trees Miller said.

On the University of Minnesota campus, there are approximately 10,000 trees, about 14 percent of which are ash trees, Grounds Superintendent Les Potts said.

Minnesota has approximately 867 million ash trees, according to the Minnesota Department of Agriculture.

“We really have a lot to lose, not only in our urban landscapes, but in our native forests,” Hahn said.

At this time, the ash trees at the arboretum and on campus are not being treated with insecticide .

“Right now, we’re in a wait-and-see mode,” Miller said.

The arboretum will be receiving traps from the Minnesota Department of Agriculture in the next two weeks, Miller said, which might be able to trap the emerging adult ash borers . Miller said he doesn’t believe it’s the right decision to inject the trees with insecticide until they know for sure that their trees are infected by the ash borers.

The problem experts are dealing with is how the ash borer got here, Hahn said. A native of China, Japan, Korea and Mongolia , the emerald ash borer can only fly about four miles a year, Miller said.

It is suspected that humans are part of the problem of spreading the insect.

“The message is, buy your firewood locally,” Hahn said.

It would have taken more than seven years for the ash borer to travel from Detroit , where it was first discovered in 2002, to Minnesota without the help of people traveling with their firewood, Hahn said.

Most research has been conducted in Ohio and Michigan. Until the University of Minnesota gets a grant, which Miller believes it will, the University is currently not conducting any research on the ash borer.

In St. Paul, the infected trees are being cut down at the end of Long Avenue , adjunct associate professor in the Entomology department , Rob Venette said. Venette is also working on finding more infected trees by pulling bark looking for the beetles.

Hahn said the ash borer has a more deadly potential than another tree-killer, the Dutch elm disease .

“Right now there is no way to stop the emerald ash borer,” he said. “We can maybe slow it down, but it’s really unlikely that we can eradicate it.”