The American chestnut was once a common and abundant tree species that occupied 200 million acres in the eastern hardwood forests of North America. The species had a cultural significance and was a keystone species, providing wildlife with food and habitat sources. Two non-native pathogens led to the chestnut's extirpation in the 20th century, but efforts are underway to conserve and restore this iconic tree.
The USDA Forest Service, The University of Tennessee, and other partners showcase their research on the American chestnut (Castanea dentata), a species that was extirpated by a non-native pathogen (Cryphonectria parasitica) that causes chestnut blight disease. Over 4,000 hybrid chestnuts that were bred for blight-resistance were planted on three national forests since 2009, and research is still ongoing.
Dr. Katie Greenberg at the AFOA Annual Meeting, 2016.
The eastern United States' mightiest tree, the oak, is in decline, possibly due to over-harvesting or climate change. Whatever the cause, scientists are trying to find ways to reverse this decline. Watch U.S. Forest Service researcher Tara Keyser and others use fire to give young oaks room to grow in the North Carolina mountains.
Six years ago the U.S. Forest Service planted 562 chestnut seedlings on this 1.5-acre plot in the Cherokee National Forest to test how hybrid chestnuts bred for blight resistance would fare in the wild. The project, which includes similar test plots in national forests in North Carolina and Virginia, is at the forefront of research aimed at restoring the once-mighty chestnut tree to the Appalachian forest.
The acorn is not only a symbol of fall, but the nuts are a baseline indicator of the current and future health of the forest ecosystem. U.S. Forest Service researchers studying acorns find a bounty of acorns indicates healthy trees and a plentiful food supply for the creatures that form the base of the forest food chain. Research Ecologist Katie Greenberg and Forestry Technician Jacquelyne Adams explain how the study of acorns can gauge the current and future health of the forest ecosystem.