"My goal and Jimbo's goal is for that thing to start producing chestnuts before me and him have to cross over the great divide."
75-year-old Rex Mann and 83-year-old Jimbo Sneed are spending their twilight years spreading the gospel of the American Chestnut tree, in hopes of restoring it to its former glory.
Back in the early 20th Century - A blight wiped out some four billion trees- stretching from Maine to Georgia.
REX MANN, RETIRED FORESTER:
"I grew up listening to chestnut stories. My dad loved the tree as did Jimbo, and he understood what it meant to the way of life of these people in the mountains had. And when we lost that tree, that way of life died with the tree. It passed away."
And they want to bring it back.
So, they helped arrange an agreement between scientists and the Eastern Band of Cherokee Indians in North Carolina to allow for the eventual planting of genetically engineered American chestnut trees on tribal land…
REX MANN, RETIRED FORESTER:
"….When a tribal member talks about this, they have credibility. And that's our - that's what we need is for the rest of the country to understand, this is a serious problem here of what we've done to our land. But there's a way to fix it. And these folks should be in the forefront of that - to help bring it back."
SNEED, CHEROKEE ELDER:
"We're always taking from the earth and never putting anything in. And, today, this gives me strength - or hope - to put in instead of take from."
For Mann - a retired forester and self-proclaimed "chestnut evangelist"- and Sneed, an elder member of the Eastern Band of Cherokee Indians, they see the union of science and nature as the key to a blight-resistant, chestnut tree revival…
Some scientists believe genetic-alteration could not only bring back the chestnut tree, but also protect other endangered trees.
Jared Westbrook is director of science at the American Chestnut Foundation.
"There is a number of species where invasive insects and pathogens have been imported into this country. The trees are not resistant. And so, you know, all the tools that we're using: the breeding, the biotechnology, the genomics, it could be used as a kind of a model for these other tree species."
Even with a signed agreement no modified tree can go into tribal soil until the U.S. government signs off on it.
Not everyone is on board with introducing genetically-altered plants into the wild.
BJ McManama of the Indigenious Environmental Network is outraged.
"The hubris of these people saying that they know what's going to happen, that this is going to be good. No, it isn't.... We don't need to be messing around with the building blocks of life and changing things that we really don't have any...We don't know what we're doing."
And others like Dana Perls of Friends of the Earth, say the modifications don't address a major contributing factor in the chestnut tree's original disappearance.
"The chestnut tree went extinct not just because of fungal blight, but also because it was over logged. There was so much logging, plus the fungal blight. What are we doing to address the root causes?"
For Sneed and Mann - they're looking for science to save the day. The two have already planted hybrid American chestnut trees in Sneed's yard.