forester on the staff, but the Great Smoky park does: Kristine Johnson. Kris Johnson is a slender woman in her fifties with a calm manner. Since 1990, she has been managing the park’s efforts to beat back exotic invaders. “We currently have about a thousand sites in the park where exotic plants have gotten in, and we’re dealing with ninety different species of invading organisms,” Johnson told me—everything from Japanese stiltgrass to princess trees and fire ants. “We knew that sooner or later we would have the woolly adelgid. People around here have a saying: ‘All the trouble comes from the North.’ But we were still surprised by how quickly it got here.”
The parasite may have been carried to North Carolina by people. In the summer of 2001, state nursery inspectors began finding infested hemlocks in nurseries in western North Carolina. The contaminated hemlocks had been imported into the state from areas where the bug was a problem. North Carolina inspectors ordered the nurseries to destroy their infested hemlocks. This was a money-losing deal for a business. “A speculation is that less-than-scrupulous nursery owners were unloading infested material on their customers,” Kris Johnson said.
Now that the insect had arrived in the Great Smokies, what weapons were available to combat it? And how many hemlocks would need to be defended? It was clear that large numbers of hemlocks grew in Great Smoky Mountains National Park, but it wasn’t immediately obvious, even to Kris Johnson, roughly how
Oil spray—the treatment that helps smaller trees in urban yards—wouldn’t work in wilderness areas, where hundreds of thousands of large hemlocks would need to be drenched every year. There were two other promising options, though. Scientists at the University of Tennessee, funded in part by a private group, Friends of the Smokies, started a small lab for breeding a kind of lady beetle native to Japan that eats woolly adelgids. It was hoped that the beetles, released into the wild, would eat lots of adelgids, cutting down their numbers and eventually getting their population reduced to the point where hemlocks could survive the infestation.
Rusty Rhea, of the Forest Service, pushed the beetle strategy forward, and researchers began releasing the beetles. The lady beetles were tiny—the size of a sesame seed—and they initially cost about two and half dollars each; a cup of them cost thousands of dollars. When they were released at test sites, they had no measurable effect. But in 2007 (after years of test releases), a test in Banner Elk, North Carolina, in which different species of adelgid-eating beetles had been released over several years, had promising results. One type of beetle, from the Pacific Northwest, got established at the site and was eating adelgids, and the hemlocks there were looking better. Even so, there remained questions about whether and how quickly such results could be achieved on a large scale —if enough beetles could be bred and released and would multiply fast enough to save the hemlock forests that were dying or were under immediate threat. The beetles might work in the long run, but by then it might be too late for most hemlocks.
There was also an insecticide treatment, a chemical called imidacloprid, which is made by Bayer. Imidacloprid had to be mixed with water and injected into the soil around the root system of a hemlock. The chemical slowly moved into the foliage. When the adelgids sucked it into their bodies, they died. Imidacloprid is an artificial kind of nicotine. (Tobacco plants produce nicotine as a natural insecticide.) The injections were labor- intensive, but there was no good alternative: if imidacloprid was sprayed from the air, it would wipe out beneficial insects and wouldn’t kill many adelgids—the insect’s woolly coat sheds water.
The chemical had some advantages: it didn’t migrate much through soil, so it would not be likely to spread widely into the environment, and it degraded quickly in sunlight. However, it was a toxic compound that could kill many grubs in the soil near the tree, as well as other insects feeding on the tree. It did not seem to affect vertebrates—frogs, salamanders, birds.
“I wouldn’t want to see chemical treatment be the only way to save hemlocks, but nothing else is ready right now,” Blozan said. “Either you get some invertebrate kill around the treatment site or you get an ecosystem collapse—that’s the choice.”
As soon as adelgids were found in the park, the Forest Service and Bayer began seeking Environmental Protection Agency permission to use the chemical in wild forests (it had already been approved for ornamental and landscape settings). The park treated ten old-growth hemlocks, as a test. Will Blozan’s company, Appalachian Arborists, was hired to climb the trees and take samples of the foliage, to see how the chemical was moving through the tree. It can take a year or two for the benefits to become noticeable; some trees die anyway. “After treatment, the hemlock can look completely dead, but sometimes it will come back, and in three years it’ll be vigorous,” Blozan said. The ones that lived would need to be retreated every few years. The hemlocks would be like AIDS patients: they would never be free of the disease, though some might survive indefinitely on drugs. “What you get is a forest on life support,” Blozan said. “But at least it can be kept alive while we hope for a cure.”
Getting funding to fight the insect in the Great Smoky Mountains park was a byzantine process. The National Park Service, Kristine Johnson’s employer, ran the park, but the Forest Service had responsibility for controlling pests in federal forests, including the national parks. The Forest Service is in the Department of Agriculture, while the National Park Service is in the Department of the Interior. Funding for insect control competes with other Forest Service needs, such as fighting forest fires. And the Forest Service appears to concentrate its pest-control efforts on trees that have commercial value—it had spent more than $100 million trying to get the emerald ash borer contained—and hemlocks aren’t worth money.
Great Smoky Mountains National Park is the most-visited national park in the United States. More than nine million people pass through the park and experience its sights each year—that’s more than twice the number of people who visit Grand Canyon National Park annually. Now the primeval rain-forest habitats of the Great Smoky national park were under grave threat. In 2003, Kristine Johnson asked for and got about $40,000 from the Forest Service to save the hemlocks in the Great Smoky Mountains park. In the next few years, the Forest Service spent about $15 million on research into ways to control the adelgid, but it spent very little to actually deploy the weapons that were available. By 2007, direct Forest Service funding for the park to fight the bugs was only $250,000 a year, with private donations increasing the total somewhat.
“The government is so damned slow,” Blozan said. “Very little was done in the first two to three years.”
Then, just as the insects appeared in the Great Smokies, Charles Taylor, a Republican North Carolina congressman who was the chairman of the appropriations subcommittee in charge of the national parks, began seeking $600 million from Congress to build a highway across Great Smoky Mountains National Park. The park was next to Congressman Taylor’s district. Because the terrain in the Great Smokies was so rugged, the road would need to include three bridges, each likely to be longer than the Brooklyn Bridge—pork spanning a wilderness. Congressman Taylor argued that local residents would need to use the road and that it would bring jobs to his district. Environmentalists called it “the road to nowhere.” The road went places in Congress, which appropriated $16 million to develop plans for it. This slug of funding tended to squeeze out other congressional appropriations for Great Smoky Mountains National Park. And none of the road money could be used for controlling the insects. In 1988, when Yellowstone National Park was devastated by forest fires, the federal government spent more than $100 million trying to put the fires out.
At any rate, the staff of Great Smoky Mountains National Park did what they could with the money they had. In 2003 and 2004, park employees treated hemlocks near public areas with imidacloprid—trees in campgrounds and along roads but not those deeper in the woods. The next year, the chemical was approved by the EPA for use in forests, and Kris Johnson and her colleagues designated special zones, called “hemlock conservation areas,” where every hemlock would be treated. Will Blozan’s company, Appalachian Arborists, won a contract and put a crew of five to work, while another crew, of eight, went to work under a park forester named Tom Remaley. The conservation areas totaled two square miles; Great Smoky park covers eight hundred square miles.
The biggest problem was carrying the water needed to mix with the chemical. The crews collected water from creeks in jugs, put the jugs in backpacks, and rhodo-wrestled their way up the mountainsides. A crew could treat between a hundred and four hundred hemlocks a day. At that pace, saving all the hemlocks in the national park was simply not possible. (Bayer later came up with a sort of a pill containing imidacloprid that could be tucked among the roots of a hemlock. The pill doesn’t require water. As this is being written, the pill is being tested. If it works, crews carrying backpacks full of pills might be able to treat thousands of hemlock trees a day.)
In no other park were officials making the kind of effort that Great Smoky officials were. “Many other parks are ‘monitoring the decline,’ as I would put it, while they’re implementing control in high-public-use areas,” Johnson said. “I could put a hundred people to work treating hemlocks.”
The woolly adelgid had not yet arrived in Cook Forest State Park, in northwestern Pennsylvania, which
