Over the course of the 20th century, an estimated four billion [American chestnut trees], one-fourth of the hardwood trees growing in Appalachia, were killed by an Asian fungus accidentally imported in the late 19th century. It’s considered one of the worst environmental disasters to strike North America—and also a preview.
Emerald ash borer, sudden oak death, Dutch elm disease, oak wilt disease, walnut canker, hemlock woolly adelgid—in a globalizing world, many trees are facing pandemics of their own. And now climate change, with its catastrophic droughts, floods, and heat waves, is making it especially difficult to fight off attackers. Even Joshua trees, icons of the southwestern desert, are finding that the world is too warm.
All this has led some scientists to ask: Can we build better trees, ones that are more able to cope? And here again the American chestnut may soon set a precedent—this time on the path to resurrection. By tweaking its DNA, scientists say, they’ve created a blight-resistant tree that’s ready for a second act. If it works for the American chestnut, perhaps it can work for other similarly afflicted trees.
