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TEAK
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TEAK ,' the most valuable of all known timbers. For use in tropical countries it has no equal, and for certain purposes it is preferable to other See also:woods in temperate climates also. Its See also:price is higher than that cf any other See also:timber, except See also:mahogany.2 See also:Great efforts have been made to find substitutes, but no timber has been brought to See also:market in sufficient quantities combining the many valuable qualities which teak possesses. The first See also:good figure and description of the See also:tree was given by Rheede,3 the best See also:modern picture being that given by See also:Brandis.4 The younger See also:Linnaeus called it Tectona grandis. It is a large See also:deciduous tree, of the natural See also:order Verbenaceae, with a tall, straight but often buttressed See also:stem, a spreading See also:crown, and the branchiets four-sided with large quadrangular See also:pith. It is a native of the See also:Indian See also:peninsula, See also:Burma and See also:Siam, and is also found in the Philippine Islands, in See also:Java and else-where in the See also:Malay See also:Archipelago. In See also:India proper its See also:northern limit is 24° 40' on the See also:west See also:side of the Aravaili Hills, and in. the centre, near See also:Jhansi, in 25° 30' N. See also:lat. In Burma it extends ' The See also:Sanskrit name of teak is See also:saka, and it is certain that in India teak has been known and used largely for considerably more than 2000 years. In See also:Persia teak was used nearly 2000 years ago, and the See also:town of Siraf on the See also:Persian Gulf was entirely built of it. Saj is the name in Arabic and Persian; and in See also:Hindi, Mahratti and the other modern See also:languages derived from Sanskrit the tree is called sag, sagwan. In the See also:Dravidian languages the name is teka, and the Portuguese, adopting this, called it teke, teca, whence the See also:English name. 2 The See also:rate in the See also:London market since 186o has fluctuated between £10 and £2o per load of 5o cub. ft. 4 Hortus Malabaricus, vol. iv. tab. 27, 1683. 4 See also:Forest See also:Flora of See also:North-West and Central India, See also:Ill. t. 44. to near See also:Myitkyina, in lat. 25° 30'. In See also:Bengal or See also:Assam it is not indigenous, but plantations have been formed in Assam as far as the 27th parallel. In the See also:Punjab it is grown in gardens to the 32nd. Teak requires a dry tropical See also:climate, and the most important forests are found in those districts of India where, during the summer months, heavy rains are brought by the See also:south-west See also:monsoon, the See also:winter months being nearly rainless. In the interior of the Indian peninsula, where the mean See also:annual See also:rain-fall is less than 30 in., teak is more scarce, and it thrives best with a mean annual fall of more than 50 in. The mean annual temperature which suits it best lies between 750 and 81° Fahr. Near the See also:coast the tree is absent, and inland the most valuable forests are on See also:low hills up to 3000 ft. It grows on a great variety of soils, but there is one indispensable See also:condition—perfect drainage or a dry subsoil. On level ground, with deep alluvial See also:soil, teak does not always See also:form regularly shaped stems, probably because the subsoil drainage is imperfect.
During the dry See also:season the tree is leafless; in hot localities the leaves fall in See also:January, but in moist places the tree remains See also:green till See also: The small oily seeds are enclosed in a hard, bony, r–4-celled See also:nut, which is surrounded by a thick covering, consisting of a dense See also:felt of matted hairs. The See also:fruit thus formed is further enclosed in the enlarged membranous calyx, in See also:appearance like an irregularly plaited or crumpled See also:bladder. The tree seeds freely every See also:year, but its spread by means of self-sown seed is impeded by the forest fires of the dry season, which in India generally occur in March and April, after the seeds have ripened and have partly fallen. Of the seeds which See also:escape, See also:numbers are washed down the hills by the first heavy rains of the monsoon. These collect in the valleys, and it is here that See also:groups of seedlings and young trees are frequently found. A portion of the seed remains on the tree; this falls gradually after the rains have commenced, and thus escapes the fires of the hot season. The germination of the seed is slow and uncertain; a large amount of moisture is needed to saturate the spongy covering; many seeds do not germinate until the second or third year, and many do not germinate at all. Where the teak tree is associated with dense clumps of See also:bamboo, natural See also:reproduction is almost absent, except when the bamboo flowers and See also:dies, and even then, if the dry bamboos and the resultant bamboo seedlings are not burnt, such young teak as may germinate are likely to be smothered at once.
The bark of the stem is about See also:half an See also:inch thick, See also:grey or brownish grey, the sapwood white; the heartwood of the green tree has a -pleasant and strong aromatic fragrance and a beautiful See also:golden-yellow See also:colour, which on seasoning soon darkens into See also: The See also:principal value of teak timber for use in warm countries is its extraordinary durability. In India and in Burma beams of the wood in good preservation are often found in buildings several centuries old, and instances are known of teak beams having lasted more than a thousand years.' Being one of the most durable of Indian timbers, teak has always been used for buildings, particularly for temples, and in India it has been the See also:chief timber employed for See also:shipbuilding. When See also:iron commenced to be exte.:sively used for the last-named purpose, it was supposed that the demand for teak would decrease. This, however, was not the See also:case, for the wood was for long very largely used in shipbuilding. and though its employment in See also:war-vessels has diminished, it is still in very great demand for " liners " and similar See also:ships. It is also used for See also:furniture, for See also:door and window frames, for the construction of railway carriages, and for many other purposes. White ants eat the See also:sap-wood, but rarely attack the heartwood of teak. It is not, however, Teak (Tectona grandis). See also:proof against the borings of the See also:teredo, from whose attacks the teak piles of the wharves in the See also:Rangoon See also:river have to be protected by a sheathing of See also:metal. Once seasoned, teak timber does not split, crack, shrink, or alter its shape. In these qualities it is See also:superior to most timbers. In contact with iron, neither the iron nor the teak suffers, and in this respect it is far superior to See also:oak. It is not very hard, is easily worked, and takes a beautiful See also:polish. It has great See also:elasticity and strength, and is not very heavy. The See also:average See also:weight of perfectly seasoned wood fluctuates between 38 and 46 lb per cub. ft .2 Its weight, therefore, is a little less than that of English oak. Green teak timber, however, is heavier than See also:water, so that, ' In one of the See also:oldest buildings among the ruins of the old See also:city of See also:Vijayanagar, on the See also:banks of the See also:Tungabhadra in See also:southern India, the superstructure is supported by planks of teakwood r z in. thick. These planks were examined in 1881; they were in a good See also:state of preservation and showed the See also:peculiar structure of teak timber in a very marked manner. They had been in the See also:building for 500 years (Indian Forester, vii. 26o). In the See also:wall of a See also:palace of the Persian See also:kings near See also:Bagdad, which was pillaged in the 7th See also:century, two Americans found in 18i1 pieces of Indian teak which were perfectly See also:sound (See also:Ouseley, Travels in Various Countries of the East, ii. 28o, n. 67). In the old See also:cave temples of See also:Salsette and elsewhere in western India pieces of teak have been found in good preservation which must have been more than 2000 years old. 2 At 44.8 lb per cub. ft. a load of 50 cub. ft. weighs a ton (2240 lb), hence in the Burma ports a ton of teak timber is taken as See also:equivalent to a load of 50 cub. ft. unless thoroughly seasoned, the wood cannot be floated. In Burma, therefore, where the See also:rivers are used to See also:float the timber to the See also:sea-ports, the method of seasoning teak by girdling has been practised from See also:time immemorial. Girdling consists in making a deep circular cut through bark and sap into the heartwood, so as completely to sever communication between bark and sapwood above and below the cut. In teak, as in oak and other trees with well-marked heartwood, the circulation of the sap only takes See also:place in the sap-wood, and the girdled tree therefore dies after a few days if the operation has been effectually performed. But if even the smallest See also:band of sapwood is See also:left connecting the outer layers of wood above and below the See also:girdle, the tree is not killed, and often recovers completely. The girdled tree is allowed to stand one or two years, and longer if a very large-sized tree. Being exposed to the See also:wind and to the See also:action of the See also:sun, the timber of a girdled tree seasons more rapidly and more completely than that of a tree felled green. The teak produced in the presidencies of See also:Madras and Bombay and in the Central Provinces is as a See also:rule felled green, and even when dry it generally is a little heavier than the timber from Burma.' For a long time to come, the rivers of Burma and Siam will continue to afford the most convenient and most economical routes for the extraction of teak timber from those countries. Indeed, the forests drained by the Salwin and its feeders are not likely ever to be worked otherwise than on the See also:present See also:plan, under which the logs are floated singly over the rapids and are caught and rafted See also:lower down, at the kyodan or rope station, 70 See also:miles above See also:Moulmein. As already mentioned, teakwood contains an aromatic oil, which gives it a peculiarly pleasant See also:smell and an oily surface when fresh cut. To this oil may probably with See also:justice be ascribed its great durability. In Burma the oil is extracted from the timber on a small See also:scale, to be used for medicinal purposes, by filling an earthen pot, which is placed inverted upon another, with chips of wood, and putting See also:fire See also:round it, upon which the oil runs down into the lower See also:vessel. According to the colour and texture of the wood, several varieties of teak are distinguished in India, Burma and Java; in the timber See also:trade, however, these distinctions are of no importance. Teak, as well as other trees, when See also:standing isolated, forms side branches far down the stem, and the wood of such trees is more knotty and wavy, and generally heavier and darker-coloured than that of trees which have grown See also:close together in a dense forest. Apart from the manner in which the tree had grown up in the forest, soil, See also:elevation and climate have a great See also:influence upon the See also:grain and the See also:mechanical qualities of teak as of other timbers. Most of the larger logs brought to market have an irregular crack or hollow in the centre, which commences at the See also:butt and often runs up a long way. There is little doubt that this is generally due to the action of the fires, which scorch and often destroy the bark of young trees. Such See also:external injuries are See also:apt to induce decay in the wood. Moreover, most teak seedlings which come up naturally are cut down to the ground by the fires of the hot season; some are killed, but many sprout again during the rains, and this is generally repeated year after year, until a sapling is produced strong enough to outlive the fire. Such saplings have a very large pith, which dries up, causing a hollow in the See also:heart; or a piece of the old shoot killed by the fire is enclosed by the new wood, and this also is apt to give rise to a hollow. The leaves of the teak tree contain a red dye, which in See also:Malabar was formerly used to dye See also:silk and See also:cotton. Natives of Burma use the leaves as plates, to wrap up parcels, and for thatching. In its youth the tree grows with extreme rapidity. Two-year-old seedlings on good sod are 5 to 10 ft. high, and instances of more rapid growth are not uncommon. In the plantations which have been made since 1856 in Burma, the teak has on good soil attained an average height of 6o ft. in 15 years, with a girth, See also:breast high, of 19 in. This is between 16° and 18° N. lat., with a mean annual temperature of 78° F. and a rainfall of See also:loo in. In the Burma plantations it is estimated that the tree will, under favourable circumstances, attain a See also:diameter of 24 in. (girth 72 in.) at the age of 80. Timber of that See also:size is market-able, but the timber of the natural forests which is at present brought to market in Burma has grown much more slowly, the chief See also:reason being the annual forest fires, which harden and impoverish the soil. In the natural forests of Burma and India teak timber with a diameter of "24 in. is never less than 100 and often more than 200 years old. In future, the timber grown in plantations and in forests under See also:regular management may be expected to be much faster grown; and there is no ground for anticipating that rapidly grown timber will be less valuable than that of slow growth, which is at present brought to market. Like the other trees of the dry deciduous forest, teak does not attain any extraordinary size. The trees are not generally more than 10o to 150 ft. high, even under the most favourable circumstances, and stems more than too ft. to the first See also:branch are not often found. Exceptionally tall trees were measured in 1861 in the Gwaythay forest in See also:Pegu, east of the Sitang river, on See also:gneiss. i It has been erroneously stated that the tree in Burma is tapped for its oil before See also:felling- The stems had 106 to 114 ft. to the first branch, with a girth, at 6 ft. off the ground, from 7 to 16 ft. Larger girths, up to 25 ft., are not uncommon. The teak tree does not usually form pure forests. It is associated with bamboos and with a great variety of other trees, which have little market value, and, as a rule, thrives best in such See also:company. Hence in the plantations established in Burma the See also:object has been to raise forests of teak mixed with bamboos and other trees. Most of the teak timber produced in India is used in the See also:country. The produce of the forests of See also:Travancore, See also:Cochin, the Madras See also:presidency, See also:Coorg, See also:Mysore, Bombay, See also:Berar and the Central Provinces is all so consumed. Formerly there was a considerable export from the ports of the western coast—Malabar, See also:Kanara, See also:Surat and See also:Broach—but the country at present requires all the teak which its forests can produce; indeed the demand is in excess of the See also:supply, and considerable quantities are imported from Burma to See also:Calcutta, Madras, Bombay and other Indian ports. Small quantities are still exported from the ports of the western coast to See also:Arabia and the coast of See also:Africa. The chief export is from Burma, principally from Rangoon and Moulmein. Of the other teak-producing countries, Java exports a little; there have also been exports from See also:Saigon; and since 1882 See also:Bangkok has sent considerable quantities to See also:Europe. But the Burma coast is the chief source of supply at present. Rangoon was for a long time an important place for shipbuilding, teak being the chief timber used: between 1786 and 1825 III See also:European vessels were built at Rangoon, aggregating 35,00o tons. At the same time timber was exported, and, when the country was taken by the See also:British in 1852, teak was the chief See also:article of export. Moulmein became British territory at the close of the first Burmese war in 1826. At that time the place was a large fishing See also:village, and it was mainly through the export of teak timber and the shipbuilding trade that it attained its present importance. From 1829 to 1841 upwards of 50,000 loads of teak timber were exported, and, in addition, 68 vessels were built during that See also:period, aggregating 15,680 tons, and estimated to have required for their construction 24,000 loads of teak timber. The forests from which Moulmein first derived its supplies are situated on the Attaran river, a feeder of the Salwin. In 1836, however, timber began to come down from more distant forests, and in 1841 one-See also:fourth only of the supply was brought from the Attaran forests. The increase in the export of timber from the Burma ports was slow at first, but has gone on rapidly since Rangoon became a British See also:port. Since that time the timber brought to the Burma ports has come from the following See also:sources:—(I) from the forests in the British coast provinces, Pegu and See also:Tenasserim; (2) from the forests in the former See also:kingdom of Burma, floated to Rangoon down the Sitang and See also:Irrawaddy rivers; (3) from the forests in the Shan states formerly tributary to Burma, from the Karenni country, and from western Siam, whence it is floated to Moulmein by the Salwin river. The following table shows the figures of the imports and exports of British India for the years 1901–2 to 1905–6: Imports. Exports. Cub. Tons. Value Rs. Cub. Tons. Value Rs. 1901—2.... 17,842 13,03,968 60,671 71,53,855 1902–3 .... 32,081 24,96,317 57,500 68,67,8.79 1903–4.... 34,588 30,55,695 73,913 91,45,605 1904–5.... 46,915 42,46,190 46,912 60,05,383 1905–6.... 71,676 62,17,331 52,768 70,41,660 1906–7.... 61,696 60,71,557 44,202 61,48,291 Average.. 44,133 38,98,483 55,994 70,60,445 _ £259,899 = £470,696 Nearly the whole of the imports came from Siam, and of the ex-ports four-fifths were from Burma. The See also:balance of the imports consisted of timber from Java, that of the exports of supplies sent from See also:peninsular ports. 'Two-thirds of .the exports went to the See also:United Kingdom, the other chief markets being ordinarily See also:Germany, See also:Ceylon and See also:Australia. The See also:recent great increase in the See also:general teakwood trade is evidenced by the fact that the imports increased in six years from 17,842 tons to 61,696 tons. But it is noticeable that, whereas in 1901–2 the timber exported very largely exceeded the imports, in 1905–6 and 1906–7 the imports were larger than the exports, See also:evidence of the great increase in Indian demand for teak timber; and, in all See also:probability, of the steady regular outturn of the Indian forests, in comparison with increased imports from Siam, where the forests are not, like those in Burma, under regular working plan, designed to give a permanent annual yield and avoid any danger of exhaustion of the forests. In British India, including Burma, a large portion of the teak-producing tracts have since 1856 been placed under conservancy management with the object of preventing overcutting and maintaining a permanent and gradually increasing supply. This is the object of the working plans referred to The See also:area of teak forest available in India and Burma is considerable, and every endeavour is made to conserve it and increase its See also:production. Similar See also:measures have been taken in Siam under the See also:advice of See also:officers borrowed from British India; and in the teak-producing native states in the peninsula the See also:necessity for careful management is now well under-stood. The teak plantations in Java had come into bearing by 1908 and it was expected that the teak areas in the Philippine Islands would be similarly See also:developed. (D. BR.; J. S. Additional information and CommentsThere are no comments yet for this article.
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