Restoration of the American Chestnut
Posted: May 3, 2012
According to the PA-TACF, the American chestnut tree was once the dominant tree in our forests before it was eradicated from our landscape by a fungus. The American chestnut was one of the largest trees in the forests of eastern North America. Some individual trees grew to be 100 feet tall and 10 feet broad (diameter) in the trunk. It grew in most areas, especially on hillsides and ridges. It was also grown in towns and around homes because of its beauty. In Pennsylvania, many forests consisted of 25% American chestnut. The American chestnut has for centuries been prized for its fruit and its beautiful, decay-resistant wood. The American chestnut was a fast-growing, rot-resistant tree that was essential to the lumber industry, and produced a reliable crop of nuts for wildlife and humans.
An "imported" fungus disease was discovered in New York City in 1904, and within 50 years it had changed the appearance of our Eastern forests. The introduction and rapid spread of the blight fungus throughout the natural range of the American chestnut has killed almost all large American chestnut trees. The loss of the American chestnut left a huge gap in our forest ecosystem.
There are several efforts underway to restore the American chestnut involving traditional breeding methods, simple conservation strategies, methods that would reduce the virulence of the blight fungus, as well as modern gene-transformation techniques. The American Chestnut Foundation (TACF) is involved with each method, but focuses primarily on classical breeding techniques. Efforts to breed blight-resistance into American chestnut appear to be successful and attempts to study reintroduction to its original range have now begun. A promising procedure called backcross breeding was started in the 1980's by the American Chestnut Foundation to breed blight resistant American chestnut trees. The Pennsylvania Chapter is participating by breeding trees adaptable to the Mid-Atlantic Region.
According to the PA-TACF, there is a constant need for fresh American chestnut pollen and nuts to keep the restoration program supplied. The PA-TACF depends upon members and volunteers across the region to find identify and document the locations of both individual trees and groups of trees. Many American chestnut trees are found where there has been a clear-cut lumbering operation. The native chestnuts spring up from the stump sprouts because the blight does not seem to harm them. Old survivors are sought as well for their potential to hold some blight resistance.
There are many hybrid American chestnuts and the PA-TACF identification screening program helps to define those that are acceptable for the breeding program. Their screening includes an evaluation of the physical characteristics and a microscopic examination. If you’d like the PA-TACF to analyze a tree you have found, or you think it would be useful to the program, you can download a “Tree Locator Form” at their website or call their office at 814-863-7192 to request a form. More information about the PA-TACF restoration efforts and how you can become involved are available at their website: http://www.patacf.org/patacfhome.htm.
The Cumberland Woodland Owners Association (CWOA) is an organization of private forestland owners and others interested in forestry issues in south central Pennsylvania. The CWOA provides information and education and is a forum for the exchange of ideas about the methods and benefits of proper forest management. The association emphasizes the awareness and implementation of best forestry management practices to sustain the forest and meet each landowner's objectives including recreational, economic and forest conservation values. For more information about the Cumberland Woodland Owners Association and the May10th meeting, contact Fred Peabody at 717/776-3565 (email: firstname.lastname@example.org).
George Hurd is the Penn State Cooperative Extension Environmental/Resource Development Educator serving Adams County. Penn State Extension in Adams County is located at 670 Old Harrisburg Road, Suite 204, Gettysburg PA 17325-3404. Phone 334-6271 or e-mail AdamsExt@psu.edu.