LANSING, W.Va. - Zeus has been growing in Mill Creek canyon for four centuries.
The massive hemlock tree stood watch as white explorers moved in, replacing the land's native inhabitants.
Zeus was there as the descendants of those explorers formed a new country, and looked on as the sons of those descendants ripped the new country apart.
The old tree, named by Adventures on the Gorge when the company set up its zip line course in 2008, has seen generations of fishermen, hunters and hikers.
Some have patted his trunk, and some have climbed his branches. Some, undoubtedly, didn't even notice the silent giant.
But Zeus might not see his 500th birthday.
There's another hemlock standing near the old sentinel. On a recent day, that tree looked like it had just received a light snowfall, except it was late April and the weather was a comfortable 70 degrees.
Almost every limb is covered with tiny white dots. They are hemlock woolly adelgid, pests that live and lay eggs in waxy coverings between a hemlock's needles.
"They feed on the starches within the hemlock tree, that the tree needs to grow and thrive," said Andrea Brandon, Central Appalachian program coordinator for The Nature Conservancy.
"It'll essentially suck the juice out of it."
Under ideal conditions, trees can live up to a decade after they've been infested.
"It can live another six to 10 years, if it's in a healthy stand and there aren't any additional stressors," Brandon said.
But ideal conditions rarely exist. If the tree encounters any other stressors, like unseasonable weather or a lack of water, death is expedited.
"If they get hit by a drought, it puts them over the edge," Bartgis said.
In the late '90s, the Mountain State saw a mild winter followed by a really hot, dry summer. Hemlocks in the Eastern Panhandle, already infested with woolly adelgid, became drought-stressed and died. Shenandoah Mountain was hit particularly hard.
"It killed over 90 percent of the hemlock trees," Bartgis said.
The hemlock woolly adelgid came to Appalachia from southern Japan over half a century ago.
Bartgis said Asia's climate is very similar to that of the United States. The woods of eastern China are filled with maple trees, oaks, pines, hemlocks and dogwood trees, just like West Virginia. It even has rhododendrons.
"You walk through their forests and they're amazingly like this," Bartgis said. "Except there are monkeys in the trees."
That makes it easy for pests like the woolly adelgid to survive the transcontinental trip, catching a ride with goods shipped from the Far East to the East Coast.
Adelgid are good hitchhikers, traveling on the wind, animal backs, bird feathers, people's clothes and tractor-trailers. The pests reproduce asexually, so it takes only one healthy bug to start an infestation.
Hemlock woolly adelgid were first spotted in the United States in 1951, in Richmond, Va., but didn't arrive in West Virginia until 1992, when arborists found them in trees in Grant and Pendleton counties.
Since then, the bug has slowly moved westward. The adelgid is only now reaching trees in West Virginia's western counties.
Bud Frantz, manager of Treetops Canopy Tour, said it was difficult to spot woolly adelgid on the Adventures on the Gorge property about four years ago.
"In a few years, it exploded," he said.
Brandon and Rodney Bartgis, state director for The Nature Conservancy's West Virginia chapter, are worried about the recent mild winter. They said temperatures were much too warm to hurt the woolly adelgid population, and the state appears to be moving into a warm, dry spring with possible drought-like conditions.
"What could be happening is the development of the perfect storm," Brandon said.
Trees in trouble
It's easy to gauge the health of a hemlock: You stand at its base and look up. If you see lots of blue sky as you peer through the canopy, the tree is not very healthy.
"Fern," the first hemlock on Adventures on the Gorge's Treetops Canopy Tour, is not very healthy. In some places, the tree offers an almost unobstructed view of the sky. Some of its branches are almost completely barren of needles.
"If we get a warm summer, that tree's going to be in trouble," Bartgis said.