Issue 11 - Science You Can Use!
How Can You Help?
by Livia Marqués
Although it may seem counterproductive to plant a tree knowing it will become infected and die, there are several reasons you might want to plant the pure American chestnut seedlings available now. The most significant reason is to preserve the diversity of native American chestnut genetic material. New plantings can help guarantee that the genetic background of living chestnuts will be conserved for a couple more generations.
The trees you plant could also be used for future breeding to support conservation efforts. With proper care, pure American chestnut seedlings can grow to 30 feet in height and be very productive before succumbing to blight. If you plant several trees, you can harvest crops of chestnuts which can further preserve the stock, give others an opportunity to plant and grow chestnuts, and provide a food source for wildlife.
Chestnuts grow well in slightly acidic soils—the same sort of conditions preferred by azaleas and blueberries. The nuts should be directly seeded in the spring, as soon as you can work the soil. Don’t plant the nuts deeper than about 1 inch in the ground and protect nuts and seedlings from rodents and deer.
Locating surviving American chestnut trees is another critical component of efforts to conserve the species. These native trees are the foundation for building a breeding stock to develop blight-resistant trees. The goal is to marry the best characteristics of the American and Asiatic chestnut species through backcrossing. It’s important to have genetic diversity in the American chestnut trees used in backcrossing, which takes at least 6 generations.
Although once a massive tree reaching over 80 feet tall, American chestnuts are now found mostly as stump sprouts, less than 20 feet tall. The native chestnut is most often confused with Chinese chestnut, chinkapin, and native hybrids.
For more information: Planting—chestnut.cas.psu.edu/Procedures/growing/planting.htm Purchasing—Pure American chestnut seeds and seedlings are available from The American Chestnut Foundation (TACF) as a member benefit. TACF also provides a list of other suppliers on its Web site at www.acf.org/seeds_seedlings.php. Identifying—(see the guide on the next page)The American Chestnut Foundation: www.acf.org/find_a_tree.php.