American Chestnut
>> Friday, December 30, 2011
Description
Scientific Names: Castanea dentata
Common Names: American Sweet Chestnut, American Chestnut, Chestnut
Plant Type: Deciduous hardwood tree.
Height: it reached up to 30–45 m (100–150 ft) tall and 3 m (10 ft) in diameter.
Native Habitat: Mostly upland forests. Dry, gravelly or rocky, mostly acid soils. This species is virtually extinct in America due to chestnut blight.
Native Range: The original range ran in a broad irregular swath from upper New England south to Alabama and Mississippi, Eastern North America - Maine and Ontario to Michigan, Georgia and Arkansas.
Conservation Status: In the first half of the twentieth century, this magnificent tree was almost completely wiped out by Chestnut Blight (Cryphonectria parasitica). Accidentally brought from Asia to New York in the 1890, the disease that required only a few decades to spread throughout the tree native range. Only a few rare trees in that area still survive along with some old stumps sometimes send their roots to shoots. Almost all of the known healthy trees are isolated specimens were planted in western states and other areas not affected by the disease. But there's a good chance that the American Chestnut can be saved and even re-established in the old range. By working with genetic material from living trees, scientists hope that the disease-resistant strains to develop. In one approach, the hybrid offspring of a resistant Asian species repeatedly crossed with pure American species, and the Asian boom features gradually bred over several generations. It is thought that this process could ultimately lead to a 98% pure American form.
Cultivation: Prefers a good well-drained slightly acid loam but succeeds in dry soils and in warm sunny places. Once established, it is very drought tolerant. Very tolerant of highly acid, infertile dry sands. Averse to calcareous soils but succeeds on harder limestones. Although very hardy, this species really live in areas with hot summers. A tree at Kew in 1985 was 15 m long and prosperous. At one time widely cultivated in North America for its edible seeds, it is now virtually extinct in the wild due to chestnut blight. There are several named varieties. Trees may become resistant, some suck ring state in America to produce fruit. Suckers often reach 4-6 m high for the indulgence of fire blight, but rarely manage to produce fruit. An excellent soil-enriching understorey in pine forests. Flowers are produced on wood of the growth in the current year. Plants are fairly self-sterile. They hybridize freely with other members of this genus. Plants in this genus are notably resistant to honey fungus.
Related Species: Allegheny Chinkapin (Castanea pumila) is a small tree from the southeast. It produces similar but smaller nuts. The species has some resistance to the disease, but can still be affected.
Scientific Names: Castanea dentata
Common Names: American Sweet Chestnut, American Chestnut, Chestnut
Plant Type: Deciduous hardwood tree.
Height: it reached up to 30–45 m (100–150 ft) tall and 3 m (10 ft) in diameter.
Native Habitat: Mostly upland forests. Dry, gravelly or rocky, mostly acid soils. This species is virtually extinct in America due to chestnut blight.
Native Range: The original range ran in a broad irregular swath from upper New England south to Alabama and Mississippi, Eastern North America - Maine and Ontario to Michigan, Georgia and Arkansas.
Conservation Status: In the first half of the twentieth century, this magnificent tree was almost completely wiped out by Chestnut Blight (Cryphonectria parasitica). Accidentally brought from Asia to New York in the 1890, the disease that required only a few decades to spread throughout the tree native range. Only a few rare trees in that area still survive along with some old stumps sometimes send their roots to shoots. Almost all of the known healthy trees are isolated specimens were planted in western states and other areas not affected by the disease. But there's a good chance that the American Chestnut can be saved and even re-established in the old range. By working with genetic material from living trees, scientists hope that the disease-resistant strains to develop. In one approach, the hybrid offspring of a resistant Asian species repeatedly crossed with pure American species, and the Asian boom features gradually bred over several generations. It is thought that this process could ultimately lead to a 98% pure American form.
Cultivation: Prefers a good well-drained slightly acid loam but succeeds in dry soils and in warm sunny places. Once established, it is very drought tolerant. Very tolerant of highly acid, infertile dry sands. Averse to calcareous soils but succeeds on harder limestones. Although very hardy, this species really live in areas with hot summers. A tree at Kew in 1985 was 15 m long and prosperous. At one time widely cultivated in North America for its edible seeds, it is now virtually extinct in the wild due to chestnut blight. There are several named varieties. Trees may become resistant, some suck ring state in America to produce fruit. Suckers often reach 4-6 m high for the indulgence of fire blight, but rarely manage to produce fruit. An excellent soil-enriching understorey in pine forests. Flowers are produced on wood of the growth in the current year. Plants are fairly self-sterile. They hybridize freely with other members of this genus. Plants in this genus are notably resistant to honey fungus.
Related Species: Allegheny Chinkapin (Castanea pumila) is a small tree from the southeast. It produces similar but smaller nuts. The species has some resistance to the disease, but can still be affected.
Castanea dentata was once the most populous species in the eastern United States, possibly numbering in excess of four billion individual trees. Many of these were real giants, to 30-45 m (100-150 ft) high and 3 m (10 ft) in diameter. Pioneers often built their huts of the rot-resistant wood, and the plants were also very valuable for wildlife. Unlike most other mast-producing trees, but generally only large plants from two to four year intervals, the chestnut is a heavy annual bearer. The nutritious nuts were a pre-primary winter food for many birds and mammals, including turkeys, bears, deer, pigs and squirrels. The events in the first half of the twentieth century, this magnificent tree is almost completely wiped out by Chestnut Blight (Cryphonectria parasitica). Now there's a good chance that the American Chestnut can be saved and even re-established in the old range. By working with genetic material from living trees, scientists hope that the disease-resistant strains to develop. In one approach, the hybrid offspring of a resistant Asian species repeatedly crossed with pure American species, and the Asian boom features gradually bred over several generations. It is thought that this process could ultimately lead to a 98% pure American form.
There is also interest in the possibility of developing resistant strains of the few trees that still survive in the disease-affected area, but right now nobody knows if it is feasible. Another possible solution to the problem is a disease-resistance gene to be inserted directly into the DNA of the American tree. This could produce a nearly 100% pure American form. It is important to preserve as much of the natural species diversity as possible, and for this reason scientists want to eventually develop a number of resistant strains. To clear the way for future work in this direction, aims to collect and preserve genetic material from a large number of surviving trees.American Chestnut is a powerful fast-growing tree. It is also to adapt to different soils and climates, and established plants can withstand drought. But because of its size and relatively rough appearance and the possible thorny nest of nut shells, it might be best suited for a woodlot or semi-wild area. If a large crop of nuts is desired, a number of trees be planted to ensure good pollination. Trees begin to bear when only a few years old.
Uses
The nuts were once an important economic resource in the United States, are sold on the streets of towns and cities. Chestnut are edible raw or roasted, but most preferably roasted. Nuts of the American Sweet Chestnut are now sold in many stores instead. Seed can be consumed raw or cooked. Rather on the small side, but these are the sweetest seeds of any species in this genus. The seed contains about 7% fat, 11% protein. It can be dried, ground into powder and then be added to cereals when making bread, cakes etc. A delicious oil can be extracted from the seed by crushing the nuts, boiling them in water and then skimming off the oil as it comes to the surface. It can be used as a topping for various puddings. The roasted nut can be used as a coffee substitute and a chocolate substitute can also be made from it.
The wood is straight-grained, strong and easy to cut and split, and it lacks the radial end grain found on most other hardwoods. The tree was particularly valuable because the market grew at a faster rate than oaks. Are rich in tannins, the wood was highly resistant to decay and therefore used for various purposes, including furniture, split-rail fences, shingles, home construction, flooring, piers, plywood, paper pulp, and telephone poles. Tannins were extracted from the bark for tanning leather. Although the larger trees are no longer available for milling, there is much chestnut wood is reclaimed from historic barns to be converted into furniture and other items.
The wood is straight-grained, strong and easy to cut and split, and it lacks the radial end grain found on most other hardwoods. The tree was particularly valuable because the market grew at a faster rate than oaks. Are rich in tannins, the wood was highly resistant to decay and therefore used for various purposes, including furniture, split-rail fences, shingles, home construction, flooring, piers, plywood, paper pulp, and telephone poles. Tannins were extracted from the bark for tanning leather. Although the larger trees are no longer available for milling, there is much chestnut wood is reclaimed from historic barns to be converted into furniture and other items.
In medicine a warm water infusion of the leaves has been used to calm the respiratory nerves and promote expectoration. The infusion has also been used in the treatment of whooping cough but modern opinion is that the leaves are no more than a mild astringent.
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