Sunday, October 10, 2010

Teak Wood

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Teak (Tectona), is a genus of tropical hardwood trees in the mint family, Lamiaceae.[1][2][3] native to south and southeast Asia, mainly India, Pakistan, Bangladesh, Burma and Thailand, and is commonly found as a component of monsoon forest vegetation. They are large trees, growing to 30–40 m (90-120 ft.) tall, deciduous in the dry season.

The word teak comes from the Malayalam/Tamil word 'Thekku

Systematics

Teak belongs to the family Lamiaceae (in older classifications in Verbenaceae). Sometimes it is included in the subfamily Prostantheroideae.[5] There are three species of Tectona:

* Tectona grandis (Common Teak) is by far the most important, with a wide distribution in Bangladesh, Thailand, China, India, and Pakistan.
* Tectona hamiltoniana (Dahat Teak) is a local endemic species confined to Burma, where it is endangered.
* Tectona philippinensis (Philippine Teak) is endemic to the Philippines, and is also endangered.


Teak is a yellowish brown timber with good grains and texture. It is used in the manufacture of outdoor furniture, boat decks, and other articles where weather resistance is desired. It is also used for cutting boards, indoor flooring, countertops and as a veneer for indoor furnishings.

Teak, though easily worked, can cause severe blunting on edged tools because of the presence of silica in the wood. Teak's natural oils make it useful in exposed locations, and is termite and pest resistant. Teak is durable even when not treated with oil or varnish. Timber cut from old teak trees was once believed to be more durable and harder than plantation grown teak. Studies have shown[6] Plantation Teak performs on par with old-growth teak in erosion rate, dimensional stability, warping, and surface checking, but is more susceptible to color change from UV exposure.

The vast majority of commercially harvested teak is grown on teak plantations found in Indonesia and controlled by Perum Perhutani (a state owned forest enterprise) trusted to manage the forest resources of Indonesia. The primary use of Teak harvested in Indonesia is in the production of outdoor teak furniture for export.

Teak consumption encompasses an array of environmental concerns, such as the disappearance of rare old-growth teak. However, its popularity has led to growth in sustainable Plantation Teak production throughout the seasonally dry tropics in forestry plantations. The Forest Stewardship Council offers certification of sustainably grown and harvested teak products. Propagation of teak via tissue culture for plantation purposes is commercially viable.

Much of the world's teak is exported by Indonesia and Myanmar. There is also a rapidly growing Plantation grown market in Central America (Costa Rica) and South America.

Hyblaea puera, an insect native to southeast Asia, is a teak pest whose caterpillar feeds on teak and other species of trees common in the region.

Teak is used extensively in India to make doors and window frames, furniture and columns and beams in old type houses. It is very resistant to termite attacks. Mature teak fetches a very good price. It is grown extensively by forest departments of different states in forest areas.

Leaves of the teak wood tree are used in making Pellakai gatti (jackfruit dumpling), where batter is poured into a teak leaf and is steamed.[citation needed] This type of usage is found in the coastal district of Udupi in the Tulunadu region in South India. The leaves are also used in gudeg, a dish of young jackfruit made in Central Java, Indonesia, and give the dish its dark brown color.

Teak is used as a food plant by the larvae of moths of the genus Endoclita including E. aroura, E. chalybeatus, E. damor, E. gmelina, E. malabaricus, E. sericeus and E. signifer and other Lepidoptera including Turnip Moth.

Teak is propagated mainly from seeds. Germination of the seeds involve pretreatment to remove dormancy arising from the thick pericarp. Pretreatment involves alternate wetting and drying of the seed. The seeds are soaked in water for 12 hours and then spread to dry in the sun for 12 hours. This is repeated for 10–14 days and then the seeds are sown in shallow germination beds of coarse peat covered by sand. The seeds then germinate after 15 to 30 days

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