American Chestnuts once blanketed the east coast, with an estimated 4 billion trees stretching from the Canadian border to the swampy southeast. They were the prototypical American tree – and now they’re gone.

These huge and ancient trees, up to 100 feet tall and 9 feet around, were treasured.

Their uses were many. The nuts were edible – chestnuts were roasted, ground into flour, and stewed in puddings – and the leaves of the trees were used medicinally.

They made many appearances in American literature, and were the wood of choice in American log cabins. Chestnuts were a major part of American life – and then they were no more.

Mature American Chestnut Tree

Finding a mature American chestnut in the woods now is so rare that the trees are “technically extinct,” according to the American Chestnut Foundation.

The blight that killed them continues to do so, so they rarely live beyond saplings anymore.

The blight, first reported in 1904, grew from an accidentally imported Asian fungus. Americans rallied to try and save the trees, cutting down infected trees as soon as the blight was soon, but it wasn’t enough.

The traumatic loss of the chestnut tree finally spurred federal laws to protect native plants from diseases they can’t resist.

A dying chestnut tree, 1916.

Though the trees are long gone from the forest canopies of the east coast, efforts to find a cure for the blight continue. In fact, they haven’t stopped since the trees started dying. Some scientists are crossing American chestnuts with Chinese chestnut trees, which are resistant to the blight, and then backcrossing the hybrids with pure American trees.

Others are infecting trees with other viruses to kill the blight. Still more are taking a cutting edge approach and sequencing the DNA of the American chestnut and the fungus that causes blight, in part to guarantee that any trees reintroduced into the wild are truly blight resistant.

The century-long drive to save the chestnut tree isn’t just about nostalgia or a funny manifestation of American exceptionalism.

The American chestnut is distinct from other varieties for both its size and how quickly it grows, which is why it was historically such a valued source of wood. And given the starring role the nuts played in American cuisine until the trees died, they tasted pretty good, too.