When the woolly adelgid come and a white cloud of tiny insects descends on the forest, the eastern hemlock dies.
It’s been like this since the insect was discovered in Virginia in 1951, where it is suspected to have arrived to the East Coast inside packing material. The sap-sucking aphid-like pest spread north first, but by the early 2000s, eastern hemlocks in the southern Appalachians were being decimated by the insect native to East Asia. By some estimates, 90 percent of the tree species’ range has been affected.
Researchers here are hatching a plan to stop the woolly adelgid. A 1-acre plot of forest is the site of a budding insectary, a farm in the trees of the predator beetle Laricobius nigrinus that has been shown in some cases to kill the adelgid.
“There’s no question a lot of hemlock have already died, a lot will still die,” said Bud Mayfield, a research entomologist at the Forest Service’s Southern Research Station and leader of the project. “I think the things we’re doing here could help with restoring hemlock in the southern Appalachians and protecting them in places still uninfested.” read more >>