When botanists were grappling with the harsh realities of the arrival of the emerald ash borer to U.S. forests, most referenced the devastation that might come to ash trees in terms of another native tree, all but wiped out by blight. That tree was the American chestnut, Castanea dentata. Scientists now have reason to hope that the majestic trees, once widespread throughout North America but virtually eliminated by the Asiatic blight fungus Cryphonectria parasitica, formerly known as Endothia parasitica, might return blight resistant.
A nonprofit organization dedicated to restoring the American chestnut to its native eastern forests, The American Chestnut Foundation (TACF) has taken part in a painstaking effort that involved crossing the tall American chestnuts with the much shorter, blight-resistant Chinese chestnuts, planting them and waiting for the seedlings to grow — a time frame of 6 to 7 years. TACF crossed the two and then back-crossed for more than six generations. The first set of intercrossed progeny from the third backcross was planted in 2002. Progeny from the second intercross, considered the first line of blight-resistant American chestnuts, were later planted in Virginia, Tennessee and North Carolina.
Experts won’t know for certain if the trees are a success, or close to the original American chestnuts, for roughly 50 years, the time it takes for a chestnut tree to grow to 100 feet. But TACF is encouraged by their progress.
Historically, American chestnuts were the dominant tree, representing 25 to 50 percent of trees in Appalachian and eastern forests. They were fast-growing trees that grew to great dimensions, often 5 to 8 feet in diameter, earning them the nickname “redwoods of the East.”
Chestnut trees were extremely important to early settlers because they produced a crop of nuts, each and every year. It also was extremely valuable as a fast-growing tree that offered lumber that was relatively light, but with the strength of oak. The trees were prized because they yielded lumber that was used to build homes, as well as furniture, paneling, cabinetry, musical instruments and caskets. Chestnut lumber is still used today, though the material comes from fallen trees or reclaimed lumber. Typically damaged by insects, the affected lumber is sold in various grades as wormy chestnut for use in furniture, cabinetry, picture frames, flooring and more.
Castanea dentata of the Family Fagaceae
American chestnut, chestnut, wormy chestnut
The average height for American chestnut is 100 feet tall. The average weight is 30 pounds per cubic foot, with a specific gravity of 0.48.
Wormy chestnut has a low bending strength and a medium crushing strength.
The heartwood is durable; however, the sapwood is susceptible to attack by the powder post beetle and common furniture beetle.
Janka Hardness: 540 lbs
Crushing Strength: 5,320 lbs
Modulus of Rupture: 8,600 lbs