Teak (Tectona), is a genus of tropical hardwood trees in the mint family, Lamiaceae, native to the south and southeast of Asia, and is commonly found as a component of monsoon forest vegetation. They are large trees, growing to 30-40 m tall, deciduous in the dry season.

The name teak comes from the Malayalam word Thekku.

Systematics

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

• Tectona grandis (Common Teak) is by far the most important, with a wide distribution in India and Indo-China.
• 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.

Cultivation and uses

The yellowish brown timber with good grains and texture from teak trunk is used in the manufacture of outdoor furniture, boat deck, and other articles where weather resistance is desired. It is also used for indoor flooring and as a veneer for indoor furnishings.

Teak, though easily worked, can cause severe blunting on edge tools because of the presence of silica in the wood. Teak's natural oil make it ideal for use in exposed locations and termite and pest proof, where it 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 shownplantation-grown teak performs on par with old-growth Teak in the following categories; Erosion Rate, Dimensional Stability, Warping, and Surface Checking.

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.

Teak consumption encompasses a different set of environmental concerns, such as the disappearance of rare old-growth teak. However, its popularity has led to growth in sustainable production throughout the seasonally dry tropics in forestry plantations. The Forest Stewardship Council offers certification of sustainably grown and harvested teak products. Experiments are ongoing to achieve vegetative propagation from one year old stem cuttings.

Popular in the 1950s and 1960s in a style often known as Danish modern, teak furniture has had a second boom in popularity. Teak is one of the most sought-after types of vintage furniture.

Leaves of teak wood tree are used in making Pellakai gatti (jackfruit dumpling), where batter is poured in a teak leaf and is steamed. This type of usage is found in coastal districts of Dakshina Kannada and Udupi in state of Karnataka in 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.

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..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.

Propagation

Teak is propagated mainly from seeds. Germination of the seeds involves 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.

Gallery of Tectona grandis (Common Teak)

Image:Teak (Tectona grandis) flowers in Anantgiri, AP W2 IMG 8807.jpg|Flowers at Ananthagiri Hills, in Rangareddy district of Andhra Pradesh, India.Image:Tree in new leaves (Tectona grandis) I IMG 8133.jpg|Tree in new leaves in Kolkata, West Bengal, India.Image:Tree (Tectona grandis) I IMG 6081.jpg|Tree in Kolkata, West Bengal, India.Image:Leaves I IMG 8820.jpg|Leaves in Kolkata, West Bengal, India.Image:Fruit (Tectona grandis) I IMG 3434.jpg|Fruit in Kolkata, West Bengal, India.Image:Falling Leaves (Tectona grandis) I IMG 3427.jpg|Falling Leaves in Kolkata, West Bengal, India.Image:Branches & falling leaves I IMG 6078.jpg|Branches & falling leaves in Kolkata, West Bengal, India.Image:Bark (Tectona grandis) I IMG 6079.jpg|Bark in Kolkata, West Bengal, India.Image:Teak Holz.JPG|Teak wood

References

1. Heywood, V.H., Brummitt, R.K., Culham, A. & Seberg, O. 2007: Flowering Plant Families of the World. Royal Botanic Gardens, Kew.
2. www.ratnasagar.co.in/language/71English_words_of_Indian_Origin.doc
3. Singh, G. Plant systematics: an integrated approach. Science Publishers, 2004
4. http://www.fpl.fs.fed.us/documnts/pdf2001/willi01d.pdf
5. Kadambi, K. (1972). Silviculture and management of Teak. Bulletin 24 School of Forestry Stephen F. Austin State University Nacogdoches, Texas
6. B. Robertson (2002) Growing Teak in the Top End of the NT. Agnote. No. G26 PDF