No one knows how much wild ginseng is taken illegally from parks and refuges across the country. But in 1999, more than 30 tons of wild ginseng roots were harvested legally from the 19 states with federally approved programs for exporting the plant. In the southern Appalachians, collecting ginseng in the wild, known as "'sanging," is part of mountain culture-with or without permits. "It's long been a traditional, walk-in-the-woods, make a little extra Christmas money kind of thing," says Garrison. "For years, we could never get anyone to look at ginseng busts as anything but glorified flower-picking cases."

Then, within a 10-day period in 1993, surveillance teams in the Great Smokies arrested two different groups of ginseng poachers, each of which were leaving the park with 13 pounds of ginseng root-the equivalent of about 8,000 plants. "That sent a shock wave through us," recalls Garrison. In response, Corbin began devising ginseng markers in the basement of his home, in a joint state-federal effort to transfer animal-marking technologies to plants. From tiny metallic strips written in Navajo (Corbin once was a missionary to western Navajo communities), the markers have evolved into the permanent dyes now used on thousands of wild ginseng plants in all corners of the Great Smokies.

The new marking efforts have allowed enforcement officials to rein in demand for park-pilfered ginseng. As legitimate dealers learn of the program and refuse to accept marked roots, poachers are being forced out of the park. And it's also allowed for the return of confiscated roots to their native lands. According to Janet Rock, a Great Smokies botanist, more than 7,000 marked plants have been seized and replanted.

Still, there's plenty of need for old-fashioned "man surveillance," as Great Smokies special agent John Mattox puts it. Rangers watch for the telltale signs of poachers in the woods. Local "'sang" hunters most often dress in subdued-colored clothing and wind up with soiled pants' knees-"no bright Yuppie jackets for them," Mattox says. They also tend to slip out of the woods one-by-one, decoying rangers away from the poacher tapped to carry the group's roots out en masse. Other plant poachers have posed as wildflower photographers. Once Garrison saw a car driven by a woman with a small child, leaving the park just a few minutes after sunrise. "I said to myself, 'That can't be right'," he recalls. He returned at the end of the day and arrested the woman's husband and father as she picked them up after a day of illegal ginseng harvesting.

Nearly 80 ginseng poachers have been convicted since the marking program began. Punishments have ranged from 60 days in jail and $2,500 in fines to "a slap on the wrist," says Garrison. Few doubt that poachers will continue to slip into the remote hollows, with a sharp stick and eyes searching for the five-leaved manroot. Corbin and his colleagues know they haven't devised a silver bullet out of orange dye and silicon. "These poachers are not dumb," says Corbin. "We have to stay in front of them, which means we'll have to reinvent the wheel in a few years." And he grins like a man with a few tricks still up his sleeve.