world news - 30.07.2007
Chinese Cousin Helps American Chestnut Tree Return
The American chestnut tree, nearly
wiped out by a blight that started more than 100 years ago, is beginning to
make a comeback thanks to its Chinese cousin. Until the beginning of the 2Oth century, American
chestnut trees dominated forests in the Eastern United States, making up one in
four trees found from Maine to Florida and west into the Ohio valley. But the majestic giants -— up to 100 feet (30.5
metres) tall and 5 feet (1.5 metre) in diameter -— were nearly exterminated by
an Asian fungus imported on plants. The fungus was discovered in New York City in 1904 and
quickly spread, killing some 3.5 billion of the trees by 1950. Government-paid workers in the Civilian Conservation
Corps during the Depression in the 1930s built cabins and lodges with the dead
trees at public campgrounds, many of which still stand today. Because it grows straight and is free of branches in
its lower half, the chestnut was favored for timber and was used for telegraph
poles, railroad ties, paneling, fine furniture and musical instruments. Millions of chestnut sprouts continually pop up from
the ground where the trees once stood, but the vast majority get killed by the
fungus before they can produce nuts. To bring the species back, scientists over several
generations bred the American chestnut with the blight-resistant Chinese
chestnut tree. Now, after 25 years of efforts, scientists at a breeding orchard
in Virginia and Penn State University are producing seeds and seedlings to
replant. The latest generation of hybrid trees have almost 95
percent of the American chestnut genes along with the blight-fighting power of
the Chinese chestnut. "In planting this tree, we are planting the hope
and making a commitment that this noble hardwood will be restored to the
American landscape and its vital ecological role in our nation's forests,"
Kempthorne said. Kempthorne said the government would work with the
coal mining industry to plant the trees on reclaimed mine sites in the
Appalachian Mountains, where the loosely packed soils allow them to take root
quickly. The hope is that nearby wildlife will then spread the
trees to neighboring forests. Because the chestnut grows rapidly, scientists say the
tree would help mitigate the effects of global warming by storing carbon dioxide
emissions that would normally heat the atmosphere.
US Interior Secretary Dirk Kempthorne planted a
blight-resistant chestnut tree outside the department's headquarters in
Washington on Thursday, pledging to help restore the tree to the American
landscape it once covered.
CHINESE HYBRID
See also:
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- — Wood products prices rise slightly
- — Finnish forest industry needs more domestic timber
- — Swedish forest industry invests in broadband
- — High hopes on cooperative to boost Japanese forest industry