ShareThisBy WADE RAWLINS
Tuesday, November 21, 2006
Forest insect researcher Robert Jetton stopped the van near a stand of eastern hemlocks in Dupont State Forest when he saw what he was seeking: tiny seed cones that could save the evergreens from extinction.
The slow-growing eastern hemlock, a pillar of Appalachian forests, grows 150 feet tall and lives 700 to 800 years. But a tiny exotic pest, the hemlock woolly adelgid, is devastating the trees. It has left forests of dead and dying evergreens from New Jersey to North Carolina. The gray trunks of lifeless hemlocks _ many of them centuries old _ stand like ghosts in the mountains.
Jetton, 32, and Andy Whittier, 31, work for CAMCORE, an international tree conservation program at N.C. State University. On a crisp mountain morning, they make an unlikely rescue team, bearing limb pruners and cloth sacks. They collect seed cones to transplant two threatened species to South America and save them from a rampant pest in this country. This fall, they have harvested cones from 36 eastern hemlocks in North Carolina, Virginia and Tennessee and 11 Carolina hemlocks, an extremely rare species, in South Carolina, Tennessee and Virginia. The cones should yield about 20,000 Carolina hemlock seeds and roughly 100,000 eastern hemlock seeds.
"We're really the Johnny Appleseeds of the world," said Bill Dvorak, director of CAMCORE, which was founded in 1980 to conserve threatened tree species in Central America and Mexico. The cooperative has expanded and now counts among its members timber companies in 15 countries that pay dues and receive technical assistance.
The work with Carolina and eastern hemlock species is CAMCORE's first effort to protect species in the United States, under a four-year, $395,000 contract with the U.S. Forest Service. "If we lost all the hemlocks here," Dvorak said, "we still would have pockets of these in other countries that we could replant."
The disappearance of the hemlock from Appalachian forests could have drastic effects on the ecosystem. Anyone who has camped by a creek in the Southern mountains has probably pitched a tent beneath hemlocks. Fishermen who have stood knee-deep in a fast-flowing trout stream have enjoyed the tree's deep shade, which keeps creeks cool and provides habitat for fish.
The adelgid, a tiny aphidlike insect that arrived on nursery plants imported from Asia, is present in 16 Eastern states. CAMCORE says it has infested hemlocks over 50 percent of their growing range. Infested trees typically die in about four years.
The pest, first confirmed in North Carolina in the mid-1990s, has spread into Great Smoky Mountains National Park, Joyce Kilmer Memorial Forest and Linville Gorge. Jetton said he has seen more evidence of dead trees in North Carolina in the past two years.
"The trees have started to decline so rapidly," said Jetton, hemlock program manager for CAMCORE and a doctoral student in entomology. "Our approach this year is to collect what we can (as) a hedge against the worst-case scenario."
Collecting cones is one of several Forest Service strategies to preserve the hemlocks. The agency is also cultivating and releasing species of beetles that eat the adelgid. But it will take several years to determine whether the beetles are slowing the adelgids' spread.
"Given the rate of decline we're experiencing in the Southeast, we want to make sure we have the potential to work with hemlocks later," said Rusty Rhea, an entomologist with the U.S. Forest Service in Asheville. "It's an insurance policy.
"Those are top-notch guys doing something hardly anybody in the world does."
Reach Wade Rawlins at 919-829-4528 or wrawlins(at)newsobserver.com.
