Source: NATIONAL GEOGRAPHIC, 10/10/16

A handful of park rangers and conservationists are trying to protect the valuable and wild root from extinction. Not long after the sun first peeks over the hills, the chill air still thick with fog, Jim Corbin sets up shop out of the back of his cherry red pickup. The North Carolina Department of Agriculture agent holds court in the back of a grocery store parking lot several times a week in the small Appalachian town of Sylva.

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