Work aims to revive chestnuts

Over 50 years, starting in 1904, 4 billion trees succumbed to blight.
SCRIPPS HOWARD
For decades it seemed the once-magnificent chestnut tree was doomed to assume its place among the sadly missing pieces of Americana. But scientific advances, and the diligence of those who hope to see it resurrected, have raised hope that the tree that once dominated the nation's landscape will make a triumphant return.
Chestnut trees were as plentiful in the Eastern United States as oaks and maples are today. About 25 percent of forested land, stretching from Maine to northern Georgia, was composed of chestnuts, and their grandeur was legendary -- Longfellow placed the village smithy under a spreading chestnut tree in one of his most famous poems.
They were a big, substantial tree, some surviving 400 years, often measuring more than 8 feet in diameter and reaching 120 feet into the sky, filled with nuts, long, thin green leaves and, starting around mid-June, tiny blooms.
"They're good for the soul," said chestnut expert Marshal Case.
Introduction of blight
But the tree known as the "redwood of the East" because of its resistance to rot and value as lumber -- at one time almost every barn in Virginia was built of chestnut -- is now an extremely rare treasure in a region where it was once abundant. Sometime in the late 1800s, a different variety of chestnut trees, perhaps from somewhere in Asia, was imported into the United States carrying blight. The affliction wasn't discovered until 1904, and it soon was determined that the American chestnut was not resistant to the disease.
Over the next 50 years, 4 billion chestnut trees, about 99.9 percent of the Eastern population, succumbed.
"There was no defense system and no time to build one," Case said.
The loss proved tragic on several levels. Residents of Appalachia lost a steady income from the lumber and the trees' nuts -- chestnuts at one time produced about 50 percent of the entire forest nut crop. Wildlife also suffered because that once-bountiful food supply all but disappeared.
Scientists' efforts
But now, more than 50 years after the tree bordered on extinction, an effort is under way to bring back the chestnut. Scientists are working to develop a blight-resistant strain in the rolling hills of southwestern Virginia, and there is hope that sometime toward the middle of the century the chestnut tree will come home.
"Our goal is to restore the American chestnut to the Eastern forest," said Case, the president and chief executive officer of the American Chestnut Foundation.
Accomplishing that ambitious objective is going to take time, Case acknowledged. The foundation is in the third year of what stands to be a 30-year project. But results thus far show promise and Case is optimistic that the venture ultimately will become the most successful nature restoration program in the nation's history.
"This data tell us that the American chestnut is such a fast-growing species that it should do well in future restoration programs," said Doug Jacobs, an assistant professor of forestry in the Hardwood Tree Improvement and Regeneration Center at Purdue University. "A lot of other species are much more sensitive, grow more slowly or just don't make it. But this tree tends to just explode out of the ground."
Resistance to fungus
The goal is to develop a tree that is resistant to the deadly fungus. Researchers hope to achieve that by taking nuts produced by the few remaining healthy trees scattered throughout their native region and cross-pollinating them with the nuts from blight-resistant chestnut trees brought from Asia. By crossing hybrids, Jacobs said, the breeding program is expected to produce trees that are, genetically speaking, 94 percent American chestnut and 6 percent Asian chestnut.
Most of the hybrid chestnuts -- about 20,000 -- can be found on two farms owned by the American Chestnut Foundation around Meadowview, Va. Another 20,000 are scattered throughout the Eastern United States on property controlled by the foundation's 13 state chapters.
Long process
"You have to go through a lot of trials," Case said. "We want to put out a product that works. Our plan right now is to achieve the early trials within the first 10 years. Then we'll plant some of the product that could have some of the nuts."
A lot of trial and error is involved, Case said. Potential trees often are killed in the process. But the foundation is looking for those that show the best resistance.
"Once a tree gets out there with a resistance capability, the fungus is going to make every effort to overcome that resistance," Case said. "So the more genes we have that can resist that fungus, the better chance we'll have trees survive in the forest."