Researchers Hope to Bring Back American Chestnuts
2024-12-24
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1"Chestnuts roasting on an open fire,Jack Frost nipping at your nose..."
2This classic song written by Bob Wells and Mel Tormé in 1944 has long brought to mind the image of Christmas for generations of Americans.
3At one time, the American Chestnut was among the most common and largest trees in the eastern United States.
4The wood was used to cover the walls of homes and schools.
5The leaves helped add nutrients to the soil.
6And men on street corners sold chestnuts cooked on open fire.
7However, in the late 19th century, some East Asian varieties of chestnut trees brought to the U.S. carried a fungus that killed almost all American chestnuts.
8The American Chestnut Foundation (TACF) is a non-profit organization based in the eastern state of North Carolina.
9It has been working with researchers for over 30 years to bring the trees back to eastern U.S. forests.
10American chestnuts now exist mostly as huge root systems that grow into small trees.
11The fungus harms them when the small trees start to develop fully.
12East Asian varieties, like those that brought the fungus in the first place, are resistant to the fungus.
13Researchers have tried to save American chestnuts by cross-breeding, or mixing, them with one kind of Chinese chestnut that can fight off the fungus.
14Progress has been slow, however. The trees the researchers have grown could not resist the fungus well enough to become large and healthy trees.
15That is why scientists are now trying to combine two methods:
16cross-breeding and genetically modifying, or changing, the genes of American chestnut trees.
17They hope this will improve the tree's ability to resist attack from the fungus.
18But, progress was delayed by a recent mix-up involving two varieties of genetically modified American chestnuts.
19Scientists at the State University of New York (SUNY) had hoped to get approval for the new seed this year.
20A changing climate and warmer temperatures may also make restoring the chestnut difficult in some areas.
21A team at Virginia Tech University published a study this summer about this issue.
22They looked at projected future climates and then measured the shortest distance the trees would have to move to survive well in a new climate.
23For now, researchers know their work might not be successful in their lifetimes.
24The process has been slow. And two of the first chestnut restoration experts, Bill Powell and Chuck Maynard, both died in the past 13 months.
25Linda McGuigan helped support Powell's and Maynard's research for years at SUNY's College of Environmental Science and Forestry.
26"The project moves on, lives on. And we honor their memory," McGuigan said.
27"I want to do something good for the future, for my children."
28I'm Andrew Smith.
1"Chestnuts roasting on an open fire, 2Jack Frost nipping at your nose..." 3This classic song written by Bob Wells and Mel Tormé in 1944 has long brought to mind the image of Christmas for generations of Americans. 4At one time, the American Chestnut was among the most common and largest trees in the eastern United States. The wood was used to cover the walls of homes and schools. The leaves helped add nutrients to the soil. And men on street corners sold chestnuts cooked on open fire. 5However, in the late 19th century, some East Asian varieties of chestnut trees brought to the U.S. carried a fungus that killed almost all American chestnuts. 6Efforts to bring back the chestnut 7The American Chestnut Foundation (TACF) is a non-profit organization based in the eastern state of North Carolina. It has been working with researchers for over 30 years to bring the trees back to eastern U.S. forests. 8American chestnuts now exist mostly as huge root systems that grow into small trees. The fungus harms them when the small trees start to develop fully. East Asian varieties, like those that brought the fungus in the first place, are resistant to the fungus. 9Researchers have tried to save American chestnuts by cross-breeding, or mixing, them with one kind of Chinese chestnut that can fight off the fungus. Progress has been slow, however. The trees the researchers have grown could not resist the fungus well enough to become large and healthy trees. 10That is why scientists are now trying to combine two methods: cross-breeding and genetically modifying, or changing, the genes of American chestnut trees. They hope this will improve the tree's ability to resist attack from the fungus. 11But, progress was delayed by a recent mix-up involving two varieties of genetically modified American chestnuts. Scientists at the State University of New York (SUNY) had hoped to get approval for the new seed this year. 12Possible effects of climate change 13A changing climate and warmer temperatures may also make restoring the chestnut difficult in some areas. 14A team at Virginia Tech University published a study this summer about this issue. They looked at projected future climates and then measured the shortest distance the trees would have to move to survive well in a new climate. 15For now, researchers know their work might not be successful in their lifetimes. The process has been slow. And two of the first chestnut restoration experts, Bill Powell and Chuck Maynard, both died in the past 13 months. 16Linda McGuigan helped support Powell's and Maynard's research for years at SUNY's College of Environmental Science and Forestry. 17"The project moves on, lives on. And we honor their memory," McGuigan said. "I want to do something good for the future, for my children." 18I'm Andrew Smith. 19Marina Walling wrote this story for The Associated Press. Andrew Smith adapted it for VOA Learning English. _______________________________________________ 20Words in This Story 21variety -n. a kind or type of something 22fungus -n. a mushroom or other plant that has no flowers, leaves, or green coloring 23restoration -n. the bringing back of something to its former condition