RALEIGH, N.C. (AP) — A years-long battle to save hemlocks in the Appalachian Mountains from a tree-killing pest has some new weapons: duct tape, a helicopter, explosives and a fresh arsenal of chemicals.
U.S. Forest Service personnel are working this week in the Joyce Kilmer Memorial Forest to eliminate some of the casualties of the struggle with an invasive insect called the woolly adelgid. About 150 dead hemlocks — some of them centuries old — threaten to tumble onto a popular trail frequented by about 35,000 visitors each year.
Steve Lohr, the district ranger who oversees hundreds of thousands of acres of national forest in the region, said duct-taping explosives to the trees appears to be the safest way to knock them over. It's an uncommon technique but carries the added benefit of leaving a jagged stump as opposed to a clean cut.
"Since it's in wilderness, we want it to look as natural as possible," Lohr said.
Meanwhile, officials are redoubling their efforts to save what's left of the decimated hemlock population. For years, massive numbers of hemlocks have been killed off by the speck-sized adelgid, a bug thought to have come from Asia a century ago that seeks nutrients inside the trees.
The aphid-like insects are thought to have arrived on ornamental plants imported from Japan in the 1920s. They showed up in urban landscaping in Virginia in the 1950s and spread through the wild in ensuing years to parts of the Northeast, the Carolinas and Tennessee.
Wood-boring insects, adelgids inject toxic saliva while sucking sap from a hemlock. Needles on infested branches go from a deep, rich green to a sickly green-gray, then dry up and fall off. Most new branch buds die.
The devastation brings great change to the wilderness. Hemlocks provide crucial shade along stream banks, halt soil erosion, give shelter to songbirds and cover for fish.
Lohr said officials will use a helicopter this year to travel over the forest canopy in search of hemlocks that are alive and haven't yet been identified. It's a search made easier in the colder months when the evergreens stand out among other trees that have lost their foliage for the year.
Crews will treat the surviving trees with chemicals, providing them a temporary lifeline until scientists can find a long-term solution for dealing with the adelgid. The most promising option is identifying and deploying beetles that prey on the bug.
"Is it bleak? Probably," Lohr said. "Do we have hope? Yes, absolutely."