Tectona grandis (PROTA)

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Plant Resources of Tropical Africa
Introduction
List of species


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distribution in Africa (planted)
1, tree habit; 2, flower; 3, fruiting twig; 4, fruits enclosed by calyx; 5, fruit with opened calyx. Source: PROSEA
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wood in transverse section
wood in transverse section
wood in tangential section
wood in tangential section
wood in radial section
wood in radial section
transverse surface of wood

plantation in Togo

young trees

inflorescence

fruiting branches

fruiting branches

infructescence

fruit

obtained from Arnhemse Fijnhouthandel

boards obtained from Arnhemse Fijnhouthandel

wood (tangential surface)

Tectona grandis L.f.


Protologue: Suppl. pl.: 151 (1782).
Family: Verbenaceae (APG: Lamiaceae)
Chromosome number: 2n = 36

Vernacular names

  • Teak, Indian oak (En).
  • Teck (Fr).
  • Teca (Po).
  • Msaji (Sw).

Origin and geographic distribution

Teak originates from the tropical forests of southern and south-eastern Asia, between 9–26°N and 70–100°E, where it may form almost pure stands. Natural stands are found in Myanmar, India, Thailand and Laos; also in small areas of China and Cambodia. Teak is one of the most commonly planted species in the tropics, between 30°N and 23°S. In tropical Africa it was introduced mainly by the Germans, in Nigeria (1889), Tanzania (1898), Ghana (1905), Cameroon and Togo (1907–1912). From the plantations in Togo seed was introduced into neighbouring countries such as Côte d’Ivoire, where the first large plantations were established in 1929 in the savanna zone near Bouaké, and Benin and Senegal in 1933.

Uses

Teak has been a highly appeciated timber for centuries in its region of origin. Wooden sculptures, doors and coffins made of teak and over 1000 years old have been found in good condition in Indian and Persian temples. Under cover, teak is considered virtually imperishable. It is the preferred wood for naval construction, elements of boat hulls and bridges of boats because of its extreme resistance to decay and corrosive activity of water. It is suitable for a variety of uses: luxury cabinet-work, frames (doors and windows), furniture and joinery with solid wood, parquet flooring, staircases, carpentry, garden furniture, railway sleepers, bridges and other construction in contact with water or the ground, electricity and telephone poles, fence posts, railcars, barrels and vats for liquids, even corrosive ones, various utensils (except tool handles because the wood is brittle), turnery and sculpturing. Through slicing teak makes nicely figured veneer. It is also used as firewood. It is often planted by farmers around fields as living fence posts and to support barbed wire. It is also planted as an amenity tree in towns and along roads.

The leaves are used for packing food products in the markets. The root bark and young leaves yield a yellowish brown, red or yellow dye, which is used to colour paper and textiles (silk, cotton or wool), but which needs a mordant. The dye from the leaves prevents blackening of yam after cooking. The leaves have a reputation of being diuretic, depurative, stimulant, antidysenteric and vermifuge, and are used in traditional medicine to treat anaemia, asthenia, fever and malaria, amoebiasis, schistosomiasis and tuberculosis. An oil extracted from young shoots is said to be used as a treatment for scabies. The flowers are used against bilious affections, bronchitis and urinary complaints; they are diuretic, as are the seeds. The seed oil is applied as a hair tonic. The astringent bark is used to treat bronchitis. The sawdust is used for the production of active carbon.

Production and international trade

Although statistics are rather incomplete, it is estimated that teak plantations cover 5.7 million ha worldwide. In tropical Africa, the area under teak plantations is about 250,000 ha, the most important countries being Nigeria (70,000 ha), Côte d’Ivoire (60,000 ha), Benin (21,000 ha), Ghana (17,000 ha), Togo (16,000 ha), Sudan (14,000 ha), Tanzania (10,000 ha) and Senegal (2500 ha).

Currently, the world production of teak (about 2 million m³/year) covers 1% of the world demand for timber, and it is the timber most in demand. In Africa the largest exporter is Côte d’Ivoire with over 100,000 m³ of logs per year (127,000 m³ in 1998), followed at great distance by Ghana, Nigeria, Togo (1700 m³ during the first 4 months of 2004) and Cameroon (40 m³ of sawn wood in 2003). Large-diameter logs from natural forest in the region of origin may fetch very high prices (in 1998 logs for veneer production fetched US$ 1700–2000/m³ and sawn wood US$ 600–1300/m³), which makes teak the luxury wood par excellence. Timber originating from plantations fetches lower prices, but between 1996 and 1999 the price (FOB) in Côte d’Ivoire reached US$ 250/m³, after which it fell. A small part of the African production is exported to Europe, but the major part goes to India, which has equipment available that is adapted to logs of small dimensions as well as ample manpower. India is the largest importer of teak, but also the largest exporter of processed teak wood.

Properties

The heartwood is brown-yellow, darkening and developing a golden shine with age. It is sometimes beige and may show darker veins, and occasionally is completely brown-black due to regular exposure to bush fires, the latter condition generally not being appreciated by the wood-processing industry. It is distinctly demarcated from the whitish sapwood, which is (1–)2–6 cm wide. The grain is usually straight, texture rather coarse. Growth rings distinct. The wood is oily to the touch and has a characteristic smell of old leather when fresh.

Teak is a medium-weight wood. At 12% moisture content, the density is (480–)610–730(–850) kg/m³. The rates of shrinkage are low, from green to 12% moisture content 0.7–1.5% radial and 1.1–2.5% tangential, and from green to oven dry 1.8–3.7% radial and 3.2– 6.2% tangential. Apparently, the rates of shrinkage are not influenced by the growth rate of the tree. Teak dries very well but rather slowly. Boards of 1 cm thick take 15 days to air dry from 40% to 15% moisture content, boards of 2.5 cm thick 30 days and boards of 4 cm thick 50 days. Boards of 2.5 cm thick can be kiln dried from 40% to 10% moisture content in 5–6 days at a drying temperature of 60–80°C, and a corresponding relative humidity of 80% to 40%. Particular care is required in determining initial and final moisture contents, as large variations in drying rates occasionally occur. The wood is very liable to colour change, and high initial temperatures should be avoided. During kiln drying a condensate of butyric acid is formed, which may corrode metal kilns (unless made of aluminium or stainless steel). Teak has low movement values and a good form stability.

At 12% moisture content, the modulus of rupture is 81–196 N/mm², modulus of elasticity 7600–17,500 N/mm², compression parallel to grain 34–70 N/mm², compression perpendicular to grain 6–8 N/mm², shear 5–16 N/mm², cleavage 14–30 N/mm, Janka side hardness 3700–4890 N and Janka end hardness 4065–4760 N.

Teak is not difficult to work, but requires some effort, mainly because of the presence of silica (up to 1.5%). Stellite-tipped saws and tools tipped with tungsten carbide are indispensable for sawing and planing operations. The wood is difficult to chisel with a hollow square mortiser, but turns well. The nail- and screw-holding capacities are good, but pre-boring is recommended to avoid splitting. Gluing is only successful on freshly machined or newly sanded surfaces. The wood bending properties are moderate; there is a tendency to buckle, and the wood is only suitable for bends of moderate curvature. Painting, staining and polishing require freshly machined surfaces or a pretreatment with thinner. However, teak can be varnished and polished beautifully. It is easy to cut into smooth, tight veneer of uniform thickness at a temperature of 90–95°C. The veneer dries flat and split-free with low shrinkage. Owing to its beautiful figure, teak is in great demand as face veneer. The wood can be peeled, but slicing gives the most beautiful and varied veneer patterns.

Teak heartwood is rated as durable to very durable. Stake tests showed an average service life in contact with the ground of more than 10 years under tropical conditions and more than 25 years under temperate conditions. However, there are indications that the durability is significantly influenced by tree age. Teak is very durable under cover. The heartwood is resistant to termite and fungal attack, and resistant but not immune to marine borer attack. The sapwood is reported to be liable to attack by powder-post beetles (Lyctus sp.). The heartwood is difficult to treat with preservatives, but treatment is usually only needed for the sapwood.

The wood contains 38–47.5% cellulose, 30–33% lignin, 12.5–14.5% pentosan, 1.1–1.4% ash and 0.2–1.5% silica; the solubility is 4.6–10.7% in alcohol-benzene, 1.2% in cold water, 11.1% in hot water and 15.6–19.8% in a 1% NaOH solution. The fine dust produced in machining operations may cause irritation of the skin or bronchial asthma and rhinitis after inhalation; a well-functioning dust extractor fan is recommended. The substance responsible for the allergic reaction is probably the naphthoquinone desoxylapachol. Another naphthoquinone, lapachol, isolated from the roots was found to have an anti-ulcerogenic effect on experimentally induced gastric and duodenal ulcers in rats and guinea-pigs. Wood extracts showed potent leishmanicidal activity. The resistance of teak wood to termites and fungi is due to the presence of tectoquinone and other anthraquinones. The energy value of the wood is 21,350 kJ/kg. The seed kernel contains about 40% oil.

Adulterations and substitutes

The wood of several tree species indigenous to Africa is traded as ‘African teak’: Baikiaea plurijuga Harms (also called Zambezi teak or Rhodesian teak), Milicia excelsa (Welw.) C.C.Berg (iroko), Oldfieldia africana Benth. & Hook.f. (also called African oak) and Pericopsis elata (Harms) Meeuwen (afrormosia).

Description

Deciduous medium-sized to large tree up to 40(–50) m tall; bole generally straight and branchless for up to 20 m, up to 150(–200) cm in diameter, at base fluted or with low buttresses; bark longitudinally fissured and finely scaly, grey to brown; crown rounded, open; young branches tetragonal, rusty brown hairy. Leaves decussately opposite, simple and entire; stipules absent; petiole 2.5–5 cm long, hairy; blade broadly ovate to elliptical-ovate or obovate, 20–60(–100) cm × 15–35(–50) cm, cuneate at base, acuminate at apex, thinly leathery, glabrescent above, hairy and scabrous below, pinnately veined. Inflorescence consisting of cymes arranged in a large terminal panicle up to 70 cm long. Flowers bisexual, regular, 5–7-merous, small, 3–6 mm long; calyx shortly lobed, persistent; corolla with a short tube and longer, patent or reflexed lobes, white with pink on the lobes; stamens inserted at the base of the corolla tube; ovary superior, ovoid, 4-celled, style slender, stigma 2-lobed. Fruit a globose drupe 1–1.5 cm in diameter, densely hairy, usually 1–2-seeded, enclosed by the accrescent calyx. Seeds ovoid, c. 6 mm × 4 mm, without endosperm. Seedling with epigeal germination; cotyledons with a notched apex.

Other botanical information

Tectona comprises 4 species, all from tropical Asia; the position of the genus within the family seems rather isolated.

Anatomy

Wood-anatomical description (IAWA hardwood codes):

  • Growth rings: 1: growth ring boundaries distinct.
  • Vessels: (3: wood ring-porous); (4: wood semi-ring-porous); 13: simple perforation plates; 22: intervessel pits alternate; (23: shape of alternate pits polygonal); 25: intervessel pits small (4–7 μm); 26: intervessel pits medium (7–10 μm); 30: vessel-ray pits with distinct borders; similar to intervessel pits in size and shape throughout the ray cell; 42: mean tangential diameter of vessel lumina 100–200 μm; (43: mean tangential diameter of vessel lumina 200 μm); 47: 5–20 vessels per square millimetre; 56: tyloses common; 58: gums and other deposits in heartwood vessels.
  • Tracheids and fibres: 61: fibres with simple to minutely bordered pits; (65: septate fibres present); 66: non-septate fibres present; 69: fibres thin- to thick-walled.
  • Axial parenchyma: 79: axial parenchyma vasicentric; 89: axial parenchyma in marginal or in seemingly marginal bands; 92: four (3–4) cells per parenchyma strand; 93: eight (5–8) cells per parenchyma strand.
  • Rays: 97: ray width 1–3 cells; (98: larger rays commonly 4- to 10-seriate); 104: all ray cells procumbent; (106: body ray cells procumbent with one row of upright and/or square marginal cells); 115: 4–12 rays per mm.

(N.P. Mollel & P. Baas)

Growth and development

Teak is a strong light demander and a long-lived poineer that may be invasive. It is said to be sensitive to competition at the level of the crown and of the roots, but it can be associated with species having a deep root system. In deep soils teak develops a taproot, which makes it resistant to winds. In more shallow soils teak develops with age several very strong superficial roots, which are concentrated in the upper 50 cm of the soil and may extend up to 20 m from the stem, ensuring its stability. Its fibrous bark makes it resistant to fires, which are favoured by the thick layer of easily inflammable litter. Some claim that fires promote the growth of teak. Fires may break seed dormancy and favour germination. From a very young age teak sprouts abundantly after fire has passed or after felling, and the sprouts form undergrowth in thinned populations. It is possible to grow a forest from tree stumps, resulting from regrowth after final exploitation by clear cutting. The abundance of sprouts can be a problem when replanting with new improved planting material.

Teak is a deciduous species. Its phenology depends on the climatic zone in which it is planted. The sprouting of buds during the first rains precedes a period of fast apical growth (one month). Flowering takes place after the period of growth in height, followed two months later by the maximum increase in diameter of the trunk. In plantations, the first flowering occurs from the second or third year. As the inflorescences are terminal, they frequently cause forking of the trunk, which sometimes disappears when the tree grows. The height under the fork, representing the height of the exploitable trunk, depends thus in general on the earliness of first flowering. An inflorescence can have up to 1000 buds, but they will not all flower. The flowering of a single inflorescence is spread over 4–6 weeks, but each flower lasts for just one day. The amount of pollen released is highest when the stigma is receptive, around noon. Insects, especially bees, take care of pollination. The level of autogamy is very low. In Côte d’Ivoire full flowering takes place during the long rainy season (May–August (–September)). Only a small percentage of the flowers give fruits. The fruits attain their maximum size about 50 days after pollination and are mature between 115–195 days after pollination. The fruiting period is 3–4 months (September–December).

In good conditions and with good provenances, the initial growth is very fast and self-pruning good. Nevertheless, as teak is sensitive to competition, its growth can slow down quite rapidly in unthinned populations, and therefore the first thinnings have to be early. With good silviculture in the best class of fertility, a well-managed plantation in Côte d’Ivoire produces a volume of about 560 m³/ha of wood when 35 years old. In poor soils or in bad rainfall conditions, growth is slow, the trunk short and the branches thick, and the production can be less than 200 m³/ha after more than 60 years. In extreme conditions, teak can survive many years in the form of bushwood.

Quite often teak trees have a number of defects such as marked grooves that can reach quite high on the trunk and dents that can sometimes be very abundant, strongly reducing the yield of sawn wood. Low forks limit the volume of timber. Sudden exposure of trunks to light at the time of thinning may lead to the appearance of a large number of water sprouts, which damages the quality of the wood.

Ecology

Tropical climates are favourable for teak if the average minimum temperatures do not fall below 18°C, if there is a marked dry season of at least two months and if annual rainfall is 1000–2500 mm; the longer the dry season, the better teak tolerates high rainfall. Teak can tolerate a marked drought in alluvial plains when groundwater is accessible for the roots. Nevertheless it is a very adaptable species that can survive with rainfall as low as 500–600 mm/year or as high as 5000 mm/year. The rainfall pattern can have one or two rainy seasons per year. Teak can also grow in areas without a distinct dry season, but will then be more susceptible to diseases such as root rot, which explains the bad results obtained in Gabon. It is frost-sensitive, but tolerates very light freezing. It tolerates repeated passages of fire.

Teak can grow on many kinds of soils except those that are subject to prolonged or permanent waterlogging. Nevertheless, teak is a very demanding species, which, for optimum growth, requires a deep, well-drained soil with a high mineral content, especially in Ca, Mg and P. It prefers soils with a neutral or slightly acid pH. It develops badly on clay, on lateritic soils with low permeability and especially in hydromorphic areas. The best results are obtained on alluvial sandy loams or sandy loamy clays, that are deep and well-drained. Teak plantations can be found from sea-level up to 1200 m altitude.

Propagation and planting

Because of the spread of flowering and fruit ripening, it is recommended to collect the fruits from the ground in order to avoid harvesting immature seeds. The seeds show orthodox behaviour and can be kept at room temperature for 2–5 years. For longer storage, it is advisable to keep them in a cold room (4°C). The teak ‘seed’ is actually a fruit which can contain up to four ‘real’ seeds. There are 800–2000(–3500) fruits per kg. Usually there are one or two viable seeds per fruit, but some fruits are sterile. The germination of a single seed lot may start after about 10 days and stop several years later; the optimum germination rate is reached at 35–45 days. It is quite difficult to break the seed dormancy and so far no reliable technique has been developed. The usual method consists of soaking the seeds in water for two days, then drying them in the sun for a whole day, and repeating this for a period of 2–3 weeks. It has been shown that large seeds germinate better and faster than small ones and that seed stored for longer than one year shows a higher germination rate. In order to stimulate germination, the seeds should not be covered completely with soil or be shaded. The germination rates are approximately 20–35%. In Côte d’Ivoire, one kg of seeds generates an average of 600 plants.

The grafting of teak, mostly shield-budding and occasionally split-grafting, is quite easy and the rate of success is almost 100%. This technique is mainly used to establish clonal seed gardens, but the stock frequently sprouts and the ‘illicit’ shoots must be removed. Layering is possible, but hardly an option for the production of large numbers of plants. Teak can be propagated by cuttings and several tens of thousands of plants are produced this way every year in Côte d’Ivoire by Sodefor (Société de Développement des Forêts). Teak can also be propagated by in vitro culture, but this technique is apparently not yet used in Africa.

Young plants originating from seeds can be grown in a seedbed (50 m² of seedbed and 6000 seeds needed for one hectare plantation). Teak can easily be planted as stumps with a rate of success exceeding 90% even without rain for 10–15 days after planting. Stumps can be stored some weeks before planting by heeling them in a shady place or in moistened jute sacks. It is not really necessary to give the roots a mud bath before planting. In Asia special methods allow the stumps to be stored for several months before planting, which makes it possible to prepare them before the dry season and to plant them as soon as the first rains begin. The planting of stumps encourages fork formation. Plants derived from in vitro culture or cuttings are mostly grown in pots. The production in pots increases the risk of malformations of the root system without markedly improving the rate of success at planting. The trees have to be planted very densely: about 1500/ha, which corresponds to a 2.5 m × 2.5 m arrangement, so that they can grow straight in search of light. For clonal plantations, a planting distance of 4 m × 4 m (625 plants/ha) is recommended.

The young plants do not tolerate competition by herbs or being shaded for too long by a canopy, even if the canopy is not dense. Fertilizers at planting enable the trees to dominate the weedy vegetation rapidly. During the first year 3 weedings are recommended, 2 during the following year and a final one during the third year. Damage to the roots during weeding should be avoided because teak is very sensitive to root rot, of which the negative effects only become visible many years later. Teak lends itself very well to the taungya system and to intercropping, both of which reduce the establishment costs of plantations. Wider planting densities are then applied to permit intercropping, and thinning of the lower branches is done from the second or third year onwards.

Management

Some say that the growth rate has little influence on the physical properties of teak wood; others state that a diameter increment of 1.2 cm/year gives optimal wood quality, while an increment of less than 0.5 cm per year leads to inferior wood. Presently there is a tendency to reduce the turn-over period to less than 25 years, while traditionally teak is harvested at 35–80 years. Thinnings have to be done early, rigorously and frequently. In Côte d’Ivoire, a first thinning is recommended when the ground surface of trees reaches 13–14 m²/ha, and a second one when it reaches 15–16 m²/ha. The tentative silvicultural standard is 3–6 thinnings 3–12 years apart and complete felling at the age of 35–80 years depending on soil fertility and the desired final diameter of the tree. The final felling represents 80% of the income, wood of the first thinnings being of low value. In Côte d’Ivoire it is estimated that the internal return rate of a plantation under the best fertility and with a felling age of 35 years exceeds 10%; the return might even be 15% in the case of clonal plantations. Other countries present even more optimistic internal rates of return.

Although teak is tolerant of fire, fires of the ground cover must be avoided to preserve the long-term productivity of teak plantations, because they leave the soil bare and cause erosion.

Diseases and pests

Attacks by several fungi, some actually killing the plants, have been recorded. In Africa, teak plantations do not seem to face serious diseases apart from root rot, which may cause severe damage, especially in the south of Côte d’Ivoire and Benin, but also in Nigeria and Tanzania. The fungal parasites are Armillaria sp., Phellinus noxius, Phaeolus manihotis, Ganoderma spp. and Rigidoporus lignosus. The last one is potentially the most dangerous. Infestation of the root system causes open places in the plantation. In Benin infestation rates vary from 1% to approximately 60% of the trees. In Benin infestation by Botryodiplodia theobromae causes die-back in patches, as does infestation by Poria sp., whereas Corticium sp. kills young branches. Fungal attacks causing damping-off may occur in nurseries, although teak is less sensitive than many other species. In zones with high rainfall and a high water table, teak suffers from a gum-disease (‘water blister’), which affects the wood quality.

In its centre of origin, more than 180 insect species have been found on teak, but only some of them (defoliators and borers) cause serious damage. Trunk borers of the genus Apate (Bostrichidae), are reported on healthy teak. Loranthaceae parasites have been found on teak in many countries, sometimes severely reducing the growth of the trees. Pests are rare in nurseries; defoliating or leaf-eating caterpillars are sometimes present, as well as termites on the roots. Rodents may constitute some danger during the germination of the seeds; baits or traps can be used to reduce the risk.

Harvesting

Usually, several thinnings are carried out in a tree population and the final harvest is by clear cutting. Independently of the growth rate, the turn-over period determines the proportion of heartwood: at 13 years 35–55% of the wood is heartwood, at 21 years 55–65%, and at an age of over 50 years more than 80%; simultaneously, the value per m³ log increases proportionally. In spite of the present tendency to fell the trees after about 20–25 years, it seems better from a technological point of view to stick to an average turn-over period (about 40 years).

The seeds are collected from the ground, from which all litter and weedy vegetation is removed. Branches can be shaken to free the ripe fruits, but fruits are not picked from the tree to avoid the harvesting of immature seeds.

Yield

Under very good conditions in Nigeria, an exceptional production of 24 m³/ha/year has been reported. In Côte d’Ivoire yields of 10–16 m³/ha/year are recorded in the forest zone, 7–10 m³/ha/year in the transition zone and 5–7 m³/ha/year in the savanna zone. In Tanzania the best plantations are said to produce up to 14–17 m³/ha/year and in a provenance trial yields of 12.2–19.6 m³/ha/year were obtained at the age of 17 years.

In seed gardens, the production of seeds amounts to 2–4(–10) kg per tree, depending on the year.

Handling after harvest

Teak is a heavy wood when green, and is not buoyant; it is therefore transported by truck, ship or train. Before storing the seeds, the papery remainders of the calyx are removed by pounding and winnowing, then the seeds are sun-dried. The seeds are urticant and allergenic.

Genetic resources

In Asia the regression of natural teak forests has been very drastic and rapid; Thailand, one of the countries of origin of teak, started importing teak wood in the early 1980s despite the establishment of the first plantations in 1910. However, due to the fact that there are many plantations in the world and especially thanks to the trials put in place by FAO and Danida since 1969, comparing 75 provenances from 16 countries (region of origin and introductions), the genetic diversity of the species is not threatened. Molecular genetic analyses confirm that there are at least two major groups: the very diverse Indian group, which is subdivided into populations from the humid, the semi-dry and the dry zones, and the more homogeneous Thai group, including some populations planted in Indonesia and Africa.

Breeding

Selection of a good provenance is essential for the success of a plantation programme in a certain environment. Because of the large variability in planting material, several countries started breeding programmes during the 1960s, which have led to the creation of seed gardens in La Sangoué, Côte d’Ivoire (clones from plus trees selected from several provenances), in Gambari, Nigeria and in Kiroka, Tanzania. These countries possess also seed-producing populations obtained by mass selection in the finest plantations.

The genetic heritability of growth in diameter is low (h²=0.41), the heritability of the absence of fork formation is average (h²=0.63), the heritability of trunk straightness is high (h²=0.88) and the heritability of thin branches is very low. The heritabilities of earliness of flowering and profuse fruiting are very high. In Côte d’Ivoire plus trees are propagated by cuttings; they are selected on the basis of the late occurrence of forking, thin branches, natural lopping and cylindrical bole. Up to now, breeding programmes do not seem to have attached sufficient importance to the wood quality.

Prospects

Teak is one of the best timbers and existing plantations are unable to meet the demand. Its numerous applications, its easy propagation and its resistance to bush fires make this tree more and more appreciated by rural communities. Although its silviculture has been mastered, the technology is not sufficiently popularized to be able to optimize the quantity and quality of its production. Nevertheless, research on the silviculture of clones must be continued because shortening the turn-over period may reduce the timber quality and harm the timber’s good image. Teak has a great future ahead, but it is necessary to obtain a good match between planting material and plantation site.

Major references

  • Baillères, H. & Durand, P., 2000. Méthodes non destructives d’évaluation in situ de la qualité du bois de teck de plantation. Bois et Forêts des Tropiques 263: 17–29.
  • Bekker, C., Rance, W. & Monteuuis, O., 2004. Teak in Tanzania. 2. La Kilombera Valley Compagny. Bois et Forêts des Tropiques 279: 11–21.
  • Bonal, D. & Monteuuis, O., 1997. Ex vitro survival, rooting and initial development on in vitro rooted vs unrooted microshoots from juvenile and mature Tectona grandis genotypes. Silvae Genetica 46(5): 301–306.
  • Dupuy, B. & Verhaegen, D., 1993. Le teck de plantation Tectona grandis en Côte d’Ivoire. Bois et Forêts des Tropiques 235: 9–24.
  • Ganglo, J.C., 1999. Phytosociologie de la végétation naturelle de sous-bois, écologie et productivité des plantations de teck (Tectona grandis L.f.) du sud et du centre Bénin. PhD thesis sciences agronomiques, Université libre de Bruxelles, Belgium. 366 pp.
  • Ganglo, J.C., Lejoly, J. & Pipar, T., 1999. Le teck au Bénin: gestion et prospectives. Bois et Forêts des Tropiques 261: 17–27.
  • Madoffe, S.S. & Maghembe, J.A., 1988. Performance of teak (Tectona grandis L.f.) provenances seventeen years after planting at Longuza, Tanzania. Silvae Genetica 37: 175–178.
  • Maldonado, G. & Louppe, D., 1999. Plantations villageoises de teck en Côte d’Ivoire. Bois et Forêts des Tropiques 262: 19–30.
  • Phengklai, C., Smitinand, T., Kartasubrata, J., Laming, P.B., Lim, S.C. & Sosef, M.S.M., 1993. Tectona L.f. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors). Plant Resources of South-East Asia No 5(1). Timber trees: Major commercial timbers. Pudoc Scientific Publishers, Wageningen, Netherlands. pp. 448–454.
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Sources of illustration

  • Phengklai, C., Smitinand, T., Kartasubrata, J., Laming, P.B., Lim, S.C. & Sosef, M.S.M., 1993. Tectona L.f. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors). Plant Resources of South-East Asia No 5(1). Timber trees: Major commercial timbers. Pudoc Scientific Publishers, Wageningen, Netherlands. pp. 448–454.

Author(s)

  • D. Louppe, CIRAD, Département Environnements et Sociétés, Cirad es-dir, Campus international de Baillarguet, TA C-DIR / B (Bât. C, Bur. 113), 34398 Montpellier Cedex 5, France

Correct citation of this article

Louppe, D., 2005. Tectona grandis L.f. In: Louppe, D., Oteng-Amoako, A.A. & Brink, M. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. Accessed 22 December 2024.