Billions of American chestnut trees once shaped life in Appalachia, but a foreign fungus erased them in a matter of decades. Today, only sickly sprouts remain — ghosts of a vanished ecosystem. Sara Fern Fitzsimmons and The American Chestnut Foundation are racing to breed resistance and restore the tree’s ecological role. It’s slow, painstaking work — but it may hold the key to revival. CLICK FOR VIDEO