The American chestnut tree, once a pillar of forests across the eastern United States, is struggling to survive.
In the early part of the 20th century, a fungus discovered after Japanese chestnut species were planted in New York City spread across the continent, decimating the American chestnut tree in less than three decades.
Now the American Chestnut Foundation is working to resurrect the species.
Their mission: finding a way to fight the blight by combining crossbreeding with genetic modification.