Researchers Hope to Bring Back American Chestnuts

2024-12-24

00:00 / 00:00
复读宝 RABC v8.0beta 复读机按钮使用说明
播放/暂停
停止
播放时:倒退3秒/复读时:回退AB段
播放时:快进3秒/复读时:前进AB段
拖动:改变速度/点击:恢复正常速度1.0
拖动改变复读暂停时间
点击:复读最近5秒/拖动:改变复读次数
设置A点
设置B点
取消复读并清除AB点
播放一行
停止播放
后退一行
前进一行
复读一行
复读多行
变速复读一行
变速复读多行
LRC
TXT
大字
小字
滚动
全页
1
  • "Chestnuts roasting on an open fire,Jack Frost nipping at your nose..."
  • 2
  • This classic song written by Bob Wells and Mel Tormé in 1944 has long brought to mind the image of Christmas for generations of Americans.
  • 3
  • At one time, the American Chestnut was among the most common and largest trees in the eastern United States.
  • 4
  • The wood was used to cover the walls of homes and schools.
  • 5
  • The leaves helped add nutrients to the soil.
  • 6
  • And men on street corners sold chestnuts cooked on open fire.
  • 7
  • However, 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.
  • 8
  • The American Chestnut Foundation (TACF) is a non-profit organization based in the eastern state of North Carolina.
  • 9
  • It has been working with researchers for over 30 years to bring the trees back to eastern U.S. forests.
  • 10
  • American chestnuts now exist mostly as huge root systems that grow into small trees.
  • 11
  • The fungus harms them when the small trees start to develop fully.
  • 12
  • East Asian varieties, like those that brought the fungus in the first place, are resistant to the fungus.
  • 13
  • Researchers have tried to save American chestnuts by cross-breeding, or mixing, them with one kind of Chinese chestnut that can fight off the fungus.
  • 14
  • Progress has been slow, however. The trees the researchers have grown could not resist the fungus well enough to become large and healthy trees.
  • 15
  • That is why scientists are now trying to combine two methods:
  • 16
  • cross-breeding and genetically modifying, or changing, the genes of American chestnut trees.
  • 17
  • They hope this will improve the tree's ability to resist attack from the fungus.
  • 18
  • But, progress was delayed by a recent mix-up involving two varieties of genetically modified American chestnuts.
  • 19
  • Scientists at the State University of New York (SUNY) had hoped to get approval for the new seed this year.
  • 20
  • A changing climate and warmer temperatures may also make restoring the chestnut difficult in some areas.
  • 21
  • A team at Virginia Tech University published a study this summer about this issue.
  • 22
  • 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.
  • 23
  • For now, researchers know their work might not be successful in their lifetimes.
  • 24
  • 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.
  • 25
  • Linda 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."
  • 28
  • I'm Andrew Smith.