Gypsy moths moving closer to Roanoke

Leaf-eating pests are marching south and west toward Va. city

July 25, 2002|By Isak Howell | Isak Howell,ROANOKE TIMES

FINCASTLE, Va. - In the pitched battle raging on the Whitemans' land, Bob would wield the blowtorch and Sue the vacuum cleaner.

The couple spent much of last spring in a desperate fight against the gypsy moth caterpillars that had denuded the stately walnut trees at their Botetourt County home. Bob Whiteman took a blowtorch to the tree trunks, incinerating the pests, while Sue vacuumed scores of them off the eaves of their home.

"We were sick, actually," Sue Whiteman said. "It got to be a little stomach-wrenching when you got to that quantity of creepy, crawly, hairy caterpillars."

The Whitemans were among the latest victims of the leaf-devouring gypsy moth, one of the premier exotic pests of Eastern forests. Now it's on a comeback - last year was a banner year for gypsy moths in Virginia. The caterpillars defoliated more than 400,000 acres in Virginia, up from 71,000 acres in 2000.

This year, private landowners and public land managers are bracing for more widespread damage, but they hope to squelch the feast by spraying insecticides designed to kill only gypsy moths.

More hope this year

This year, the Whitemans have more hope. They were instrumental in getting Botetourt County started in the federal program that helps pay to spray private land for gypsy moths.

The non-native moths are marching south and west toward Roanoke every year. In their path, they leave naked trees, some of which don't survive the assault. Sue Whiteman estimates roughly half of the oak trees - the moths' preferred tree - on their 40 acres were killed by last year's infestation.

Statewide, 63,000 private acres, including 1,702 acres in Bath County, were sprayed in the federal program and 9,000 acres were sprayed in the George Washington and Jefferson National Forests and along the Blue Ridge Parkway recently.

Last year 34,000 acres were sprayed in the cost-share program, and in 2000, just 4,300 acres were sprayed. The numbers reflect a swelling population, possibly due in part to mild, dry winters that don't kill the moths and do hamper a fungus that has killed many of the moths in other years.

Native to Europe and Asia, the moth was brought to Massachusetts in 1879 when a French astronomer carried it over in search of a new strain of silk moth for commercial use. Major damage began 20 years later and didn't come in force to Virginia until about 1980. Now the caterpillars annually defoliate millions of acres from North Carolina to Canada and west to Wisconsin.

A fungus, also not native to America, was introduced in the early 1900s to control the moth. The fungus was largely responsible for keeping the moth's destruction in check for several years in the mid-1990s, but a new upswing has begun.

`Picked up big-time'

"It's picked up big-time just about everywhere, and I think that has to do with the mild winters we've had," said Dee Dee Sellers, a U.S. Forest Service entomologist.

Others hope the weather will allow the fungus to grow and eventually kill many of the caterpillars. Beyond faith in the fungus, damage control means using helicopters and airplanes to spray forest with one of several agents that kill the caterpillars. The one used on the Whitemans' land prevents the caterpillars from molting, killing them as they grow out of their skins.

There are programs to slow the rate of infestation in counties south and west of Roanoke. But with many caterpillars carried by the wind and egg masses hitching rides on vehicles, stopping the spread is nearly impossible.

That leaves the situation of a continuing, widening battle that descended on the Whitemans. The cost-share program allowed them to treat their land for about $12 an acre, with other costs reimbursed to Botetourt County by the federal government. It's voluntary, and some landowners vehemently oppose the spraying as earnestly as the Whitemans craved it. Some landowners, wary of insecticides as well as government intrusion, don't want their land sprayed.

Joyce Coiner, who coordinates the cost-share program in several counties, said her phone will ring off the hook as soon as landowners notice their naked trees and hordes of caterpillars. For them, it's too late to do anything this year except to sign up for spraying next year.

How many trees die depends on how stressed the trees already are. Tim Tigner, Virginia Department of Forestry forest health specialist, said the trees are already suffering from three years of drought, making each defoliation more likely to be deadly.

He sees the moth as another player in the expanding drama of invasive species, many of which were introduced by humans who only later realized the resulting damage.

"We're doing this to ourselves increasingly," Tigner said. "It's a no-win game."

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