In this Wednesday, Oct. 10, 2012 photo, Traylor Renfro examines an American chestnut seedling growing from a diseased stump on his property in Grassy Creek, N.C. The American chestnut tree, the "redwood of the East," once towered over everything in the forest from Georgia to Maine. It provided the raw materials that fueled the young nation's westward expansion, and inspired poets. Then a blight struck, and by the 1950s, this mightiest of trees was all but extinct - "gone down like a slaughtered army," in one naturalist's words. A 50-foot chestnut nearby has yet to show signs of the blight that has all but wiped out the species. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, tree geneticist Paul Sisco leads members of The American Chestnut Foundation on a hybrid orchard tour outside Asheville, N.C. All claims of a naturally resistant American are "baloney," said Sisco, a retired American Chestnut Foundation staff geneticist. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, members of The American Chestnut Foundation tour a hybrid orchard outside Asheville, N.C. The organization is using such orchards to develop a tree that is mostly American, but will resist the blight that has driven it to near extinction. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, a chestnut seedling sprouts in the shadow of an older tree in a test orchard outside Asheville, N.C. The American chestnut tree, the "redwood of the East," once towered over everything in the forest from Georgia to Maine. It provided the raw materials that fueled the young nation's westward expansion, and inspired poets. Then a blight struck, and by the 1950s, this mightiest of trees was all but extinct _ "gone down like a slaughtered army," in one naturalist's words. Now, after 30 years of breeding and crossbreeding, scientists have developed a potentially blight-resistant tree. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, members of The American Chestnut Foundation tour a hybrid orchard outside Asheville, N.C. The organization is using such orchards to develop a tree that is mostly American, but will resist the Cryphonectria parasitica fungus, that has driven it to near extinction. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, an orange-black canker erupts on a hybrid chestnut tree in a test orchard outside Asheville, N.C. Entering through wounds in the bark, the fungus threads its way through the straw-like vessels that carry water and nutrients from the ground to the tree's crown. As the tree responds to plug these holes, the blight works its way around the trunk "until it is completely girdled," William A. Murrill, the botanical garden's assistant curator, wrote in 1906. "The tree essentially commits suicide," said geoscientist Frederick Paillet, an emeritus professor at the University of Arkansas who has studied chestnuts for nearly a half century. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, geoscientist Fred Paillet, an emeritus professor at the University of Arkansas who has studied chestnuts for nearly a half century, listens to a speaker during the American Chestnut Summit in Asheville, N.C. After 30 years of breeding and crossbreeding, scientists have developed a potentially blight-resistant tree. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, University of Pennsylvania Professor Kim Steiner addresses an audience during the American Chestnut Summit in Asheville, N.C. "The restoration of American chestnut is a really impractical idea. Some people might say it's a nutty idea," Steiner acknowledged. But, he said, it is “a compelling idea..., a romantic idea..., an emotional idea. And that's where the motive comes from. That's where it has to come from to sustain this program." (AP Photo/Allen Breed)

This Wednesday, Oct. 10, 2012 photo shows an American chestnut tree on Traylor Renfro's mountaintop retreat in Grassy Creek, N.C. About 50 feet tall, the tree has yet to show signs of the blight that has all but wiped out the iconic American species. (AP Photo/Allen Breed)

In this Wednesday, Oct. 10, 2012 photo, Traylor Renfro holds two burs from an American chestnut tree, center, on his property in Grassy Creek, N.C. (AP Photo/Allen Breed)

In this Friday, Oct. 19, 2012 photo, Jim Hurst stands in a chestnut orchard planted on his hillside farm outside Asheville, N.C. The hybrid chestnuts on Hurst's property - some of which have grown to an impressive 20 feet in height - contain genetic material from three North Carolina "mother trees." Scattered among the "families," as a scientific control, are several offspring of a Chinese chestnut. (AP Photo/Allen Breed)

In this Wednesday, Oct. 10, 2012 photo, burs from an American chestnut tree litter the ground on Traylor Renfro's hillside retreat in Grassy Creek, N.C. Thoreau wrote lovingly of going "a-chestnutting" in the New England woods. In an 1857 journal entry contemplating the chestnut's spiny bur, he rhapsodized on the wonderful care with which nature "has secluded and defended these nuts, as if they were her most precious fruits, while diamonds are left to take care of themselves." (AP Photo/Allen Breed)

This circa 1910 image provided by the Forest History Society via the The American Chestnut Foundation, shows woodsmen with three huge American chestnut trees near what is now the Joyce Kilmer Memorial Forest outside the Great Smoky Mountains National Park in western North Carolina. The "redwood of the East," once towered over everything in the forest from Georgia to Maine. It provided the raw materials that fueled the young nation's westward expansion, and inspired poets. Then a blight struck, and by the 1950s, this mightiest of trees was all but extinct - "gone down like a slaughtered army," in one naturalist's words. (AP Photo/Forest History Society via the The American Chestnut Foundation)