Chestnut Blight

The American chestnut (Castanea dentata) was an iconic tree that is now functionally extinct. For a hundred years, researchers from multiple organizations have been working to restore this tree. A free online course – An Introduction to the American Chestnut – is now available. The course covers chestnut taxonomy, silvics, historical importance, ecology, and its demise. A second course in development will cover American chestnut restoration and management.

Sometimes reaching a height of more than 100 feet tall with trunk diameters often well over 10 feet, the American chestnut was the giant of the eastern U.S. forests. There were once billions of them and their range stretched from Georgia and Alabama to Michigan, but the majestic tree was gone before forest science existed to document its role in the ecosystem. Notes left by early foresters including Gifford Pinchot, the founder and first chief of the USDA Forest Service, suggest that its ecological role was as impressive as the tree's size. Mature American chestnuts have been virtually extinct for decades. The tree's demise started with something called ink disease in the early 1800s, which steadily killed chestnut in the southern portion of its range. The final blow happened at the turn of the 20th century when a disease called chestnut blight swept through Eastern forests. But, after decades of work breeding trees, The American Chestnut Foundation, a partner in the Forest Service's effort to restore the tree, is close to being able to make a blight-resistant American chestnut available.