American Chestnut: Tree of Hope

American Chestnut: Tree of Hope. . , The American Chestnut Before 1900 , Prior to the 1900's, American chestnut (Castanea dentata) was the dominant hardwood in much of the eastern deciduous forest. In early summer, chestnut trees in flower made Appalachian ridgetops appear snow-capped. A large chestnut could reach over 100 feet tall and up to 10 feet in diameter., Chestnuts were a staple food for bears, turkeys, deer, and other animals. Local residents harvested the plentiful, dependable nuts for their own consumption and as a cash crop. The wood was light, strong, easy to work, and rot resistant; It was used for everything from fences, cabins, and railroad ties to furniture and musical instruments., The Chestnut Blight , Introduction of the chestnut blight prior to 1900 was an ecological disaster. Accidentally imported on blight resistant Asian chestnuts, this fungus (Cryphonectria parasitica) spread rapidly throughout the American chestnut's range. By the 1950's, billions of chestnuts had died up and down the east coast., Chestnut blight infects and quickly kills above ground tissue, but not the root system often survives. New stems then sprout from these roots. Once stems reach a couple inches in diameter, however, they, too, become infected and die. This results in shrubby growth seen in the photo at left., Restoring the American Chestnut , The American Chestnut Foundation (TACF) is coordinating a long-term breeding program designed to introduce blight resistance into the American chestnut. Genes for blight resistance were introduced into American chestnuts, which are resistant to the blight., Hybrid trees were then backcrossed to pure American chestnuts at least four times in order to restore most of the American chestnut genome and result in a tree that looks like and performs like the native American trees. Each generation, hybrid trees are inoculated with the blight, and only those that do well (and likely carry resistance genes) are used in the backcrossing program. This requires several generations, and therefore, many years., Test Trees on Mill Mountain , In October 2010, Mill Mountain Garden Club, in collaboration with the City of Roanoke, The American Chestnut Foundation, and The Garden Club of America, planted 5 hybrid chestnuts., These trees are part of a network testing locally adapted strains of American chestnut. Similar efforts are under way up and down the east coast in hopes of breeding an American chestnut that can thrive in the face of this deadly fungus.