Bringing firewood to campsites threatens state’s forests

Published: August 30, 2012

CLEMSON — Labor Day weekend is here and campers can escape to the woods, pitch tents, roast marshmallows — and destroy South Carolina's beautiful ash trees.

That's what can happen when they tote their own firewood into campsites.

"Bringing firewood into state parks and campsites from other places is a leading cause of importing invasive species into our forests," said Sherry Aultman of Clemson University’s department of plant industry. "It seems like such a simple, innocent thing, but it can be deadly to our native trees."

Firewood can harbor any number of nasty bugs, both under the bark and inside the wood itself.

Among the most sinister is the emerald ash borer, Agrilus planipennis, a green beetle native to parts of Asia.

The pest arrived in North America just over a decade ago, likely stowing away aboard a cargo ship in wooden packing crates. First identified in the upper Midwest, it spread rapidly to more than a dozen states and parts of Canada, devastating ash trees along the way.

The emerald ash borer already is one of the most destructive invasive species in the United States, according to the U.S. Department of Agriculture. As many as 100 million ash trees have been lost so far, and with no effective means to control the borer, infestation means certain death for ash forests.

Clemson University’s Regulatory Services division, which is charged with monitoring and, when possible, eradicating invasive plant and pest species in South Carolina, has set up traps in forests throughout the state to provide an early warning of the pest’s arrival.

The distinctive two-foot-long purple traps, which hang from tree limbs by a metal hook, include a natural plant oil scent to attract the beetles and are covered with a glue that will capture them. Purple was chosen because it's the color most likely to attract the bugs.

“The emerald ash borer has been discovered as far south as Virginia,” said Aultman, who coordinates Clemson’s Cooperative Agricultural Pest Survey (CAPS) program. “It’s not a matter of if, but when the ash borer gets here. We’re trying to be as alert as possible to slow their spread.”

Adult ash borers, which munch the tree's foliage, aren't a direct threat. But their progeny — voracious larvae about the size of a grain of rice — chow down on the inner bark of the tree, destroying its ability to distribute water and nutrients.

The object of their appetite, the ash tree, is prized for the quality of its wood. The hard, strong and shock-resistant ash wood is the star attraction of America's favorite pastime: More than half the wooden baseball bats in the United States come from ash, and the wood is widely used to make furniture and flooring.

“South Carolina is fortunate to have several different species of ash trees,” Aultman said. “They’re a beautiful tree and also a very useful one. We want to protect them as best we’re able.”

The best weapons, she said, are vigilance and caution.

“Firewood from other areas is a major contributor to the introduction of invasive pests. Even firewood that looks clean and healthy can have fungi or insects that could start a disastrous infestation,” Aultman said. “It’s simply not worth the risk. Take advantage of the firewood for sale at the parks themselves. You’ll save yourself a headache and potentially save a forest.”

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