American chestnut trees once blanketed the east coast, with an estimated 4 billion trees spreading in dense canopies from Maine to Mississippi and Florida. These huge and ancient trees, up to 100 feet tall and 9 feet around, were awe-inspiring, the redwoods of the east coast, but with an extra perk — the nuts were edible. Chestnuts were roasted, ground into flour for cakes and bread, and stewed into puddings. The leaves of the trees were boiled down into medicinal treatments by Native Americans. The trees make appearances throughout American literature, like in Thoreau’s journal, where he considered his guilt over pelting them with rocks to shake the nuts loose while he lived in Walden woods, musing that the “old trees are our parents, and our parents’ parents, perchance.” Chestnut trees offered shade in town squares, were the wood of choice for pioneers’ log cabins, and were a mainstay of American woodcraft. In short, chestnuts were part of everyday American life. Until they weren’t.
Finding a mature American chestnut in the wild is so rare today that discoveries are reported in the national press. The trees are “technically extinct,” according to The American Chestnut Foundation. The blight that killed them off still lives in the wild and they rarely grow big enough to flower and seed, typically remaining saplings until they die. Essentially, the giant trees were reduced to shrubs by the 1950s.
The problem was a fungus imported from Asia that spread easily, attaching to animal fur and bird feathers. Spores were released in rainstorms and tracked to other trees through footsteps. The fungus infected trees through injuries to the bark as small as those created by insects. “It looks like a target filled full of small shot holes,” one Pennsylvania paper reported as the blight spread.
The first chestnut tree may have been infected as early as the 1890s, with blight first reported in 1904 when it was spotted on a tree in New York’s Botanical Garden. Panic over the blight was widespread by the 1910s. State commissions were formed. Farmers were implored to chop down trees with any signs of blight. “Woodman, burn that tree; spare not a single bough,” begged The Citizen, a paper from Honesdale, Pennsylvania, the heart of the chestnut tree’s range. Even the Boy Scouts pitched in to try and save the chestnuts, scouring forests for blighted trees as part of a multi-state effort to create an infection-free zone.
The combined powers of the public, scientists, and the governments weren’t enough to save the chestnuts. The loss was stunning, both financially and emotionally. “Efforts to stop the spread of this bark disease have been given up,” The Bismarck Daily Tribune resignedly reported in 1920. The paper estimated that the value of the trees was $400,000,000 as recently as a decade before.
The end of the trees marked the end of a “conspicuous and beautiful feature of the landscape in this country,” and the Daily Tribune predicted with incredulity that “schoolboys of the future who read the poem of the village blacksmith will ask, What is a chestnut tree?” (the allusion was to the first line of a Longfellow poem). The traumatic loss of the chestnut tree finally spurred federal laws to protect native plants from diseases they can’t resist.
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.