Maine news, sports, weather from Portland Press Herald / Maine Sunday Telegram, Portland, Maine

July 26, 2012

Invasive emerald ash borer poses threat to Maine trees

The insect has spread into central Connecticut and is heading north.

By North Cairn ncairn@pressherald.com
Staff Writer

An insect that threatens Maine's ash trees has spread into central Connecticut, as it steadily makes its way toward northern New England.

The emerald ash borer, an invasive species of metallic-green beetle, kills in its larval stage by eating into the wood beneath the bark of ash trees and effectively girdling them, cutting off the flow of vital nutrients.

"It could be here," said Charlene Donahue, forest entomologist with the Maine Forest Service. "We don't feel we have much time at all."

Thought to have made its way into North America on wood-packing products from Asia, the highly destructive beetle was first discovered 10 years ago in the Midwest and has been moving inexorably east and somewhat south in the United States and into parts of Canada, decimating millions of ash trees in its path, said Maine state entomologist Dave Struble.

Officials believe the beetle spread in the states in firewood transported from state to state. It has jumped the Hudson River, appearing along the Massachusetts border and most recently near Prospect, Conn.

That means it now is doing its damage within a half-day's drive from Maine -- alarming because many summer day-trippers and campers come here from nearby New England states and, as part of their stays, enjoy campfires. Consequently, residents and visitors alike have been asked not to transport firewood over state lines.

Last summer, state forest service officials made random checks of cars coming into Maine to make sure no firewood slipped through, partly to monitor the pest but also to educate people. This year, traps and biological methods are being used to detect the beetles' arrival.

"Sooner or later, it's going to get here," Struble said. "It's certainly not a great big shock; it's disheartening, though. The whole situation concerns me a lot."

About 6.7 million cords of ash wood are harvested in Maine each year, with a value of about $140 million annually, said Kenneth Lautsen, biometrician for the Maine Forest Service.

Those statistics reflect that ash trees do not constitute "a big component of our forests here in Maine," he said, but their loss would have a significant impact on forests and on industries which use the tree's wood in products, including furniture, that require strength and flexibility.

And "it's not just industry" that would be hurt, Donahue said. Beyond these threats lies perhaps the most crucial consideration of all -- "the way everything works together in an ecosystem."

When the trees are debilitated or killed, there's a ripple effect: Birds which might nest in the branches must find other safe haven, and wildlife which might seek shelter or food there must look elsewhere.

Take away the ash, and you remove the essential biodiversity of the forest in which it once thrived. "If we only end up with red maple," Donahue said, "there won't be everything you need to support the ecosystem."

The fruit of the ash provides food for quail, wild turkey, grouse, finches, grosbeaks and other songbirds, while young twigs and leaves provide vegetation on which deer and moose browse, according to material from the University of Maine Cooperative Extension.

"If (ash) follows the same pattern as in the Midwest, we will lose most" of the state's ash trees, Struble said. The result "would not be an ecological desert," he said, "but completely losing anything slims down your biodiversity, your resiliency. We'd be biologically the poorer."

But the imminent risk to ash trees, which typically grow to 70 or 80 feet tall, represents more than a loss to industry or an ecological concern about diminishing diversity among all the life of the northern woods; it constitutes a cultural threat, too.

(Continued on page 2)

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