Steve Bost will show you some Ozark chinquapin trees. “But I’d have to blindfold you before you get in the car,” he jokes.

Deep in the rolling southeast Missouri Ozarks, Bost gets out of his car at the end of a remote dirt road. Somewhere nearby, carefully hidden from the public, is the Ozark chinquapin tree, once a keystone Ozark forest species. Decimated by chestnut blight in the mid-1900s, any viable trees were thought to be long gone—that is, until Bost found a few healthy hangers-on in the 2000s. Now he’s trying to bring the tree back from the edge of blight in a non-traditional way. And he’s succeeding.

Bost wipes his face with spicebush leaves, a natural repellent for a