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teak, tall deciduous tree (Tectona grandis) of
the family Verbenaceae (verbena family), native to India and Malaysia but now
widely cultivated in other tropical areas. Teakwood is moderately hard, easily
worked, and extremely durable; beams said to be over 1,000 years old are still
functional. The wood contains an essential oil that resists the action of water
and prevents the rusting of iron. The heartwood is resistant to termites. Teak
is superior to all other woods for shipbuilding and is also used for furniture,
flooring, and general construction. Several other similar woods from unrelated
trees are sometimes also called teak. Teak (Tectona grandis) is
classified in the division Magnoliophyta,
class Magnoliopsida, order Famiales, family Verbenaceae. The Teak trees
buttresses ( roots that hold trees with shallow roots) can grow up to 20 feet
tall! Other trees buttresses don't grow that tall. The Teak tree has a fruit
called the Drupe. The Drupe has a hard shell on the outside a juicy middle and a
hard seed. A lot of animals in the canopy eat this fruit. The Teak tree is a
fast growing tree. It grows the easiest in red soil. Teak at about 12 days old
can grow up to 4" tall. Teak at 6 months is already 10 feet tall. Teak can
grow 10 feet taller when 1 year goes by. Teak can grow to 50 feet tall in 3
years!
When the Teak is fully grown it can grow up to 150 feet tall!
Natural distribution: Burma, India peninsula, west of Thailand and Indonesia in between 25 and 12 degrees north in latitude, and 104 and 73 degrees east in longitude. (1)
Artificial distribution: Introduced in Trinidad and Tobago in 1913, with seeds of Tenassarim in Burma. This original seed source was then distributed from Trinidad and Tobago to the majority of tropical countries, including Costa Rica (1)
Environmental requirements: For optimal growth teak need to be planted within an altitude range in between 0 - 600 meters above sea level, precipitation levels between 1,250 and 3,000 mellimeters, a median temperature of 25° - 28°C, and a definite dry season between 3 and 5 months. (1,2,4,5,7) This species is adaptable to a large variety of soils, well drained, fertile and deep; preferring a sandy loam or clay soil, with a neutral or acid ph level (1,7) The topography must be flat or undulated, with slopes inferior to 25% incline. If planted in an area with a steeper incline one must take special precaution in maintaining the undergrowth below the tree, to avoid erosion. (1,7) Will tolerate soils which are slightly rocky, requiring soils of medium to high fertility being susceptible to constant strong winds. (1,7)
Limiting factors: Poorly drained shallow soils or compacted heavy clay, without a specific dry period or in heights above 1000 meters above sea level. It is susceptible to competition with weeds, fire and ants (Atta. Sp.). Because of it's wide leaf it tends to provoke erosion of the soil in steep areas (above 35% incline) because of it's ability to hold large amounts of water and precipitation in it's foliage. (1,2,4,5,7)
Characteristic of the wood: It is fine and hard, contains silica, it's easy to work with dries and preserves well it's durable and has good dimensional stability. It's not corrosive and is resistant to termites, fungus and weather. It contains an oil which makes it resistant and protects it against the attack of various organisms. It is considered one of the most valuable woods in the world. (1,7)
Diseases and plagues: It is highly resistant to the attack of fungus and insects, not suffering from any particular one of importance. (1,3,7)
Establishment: Before the establishment of the plantation, the seeds are collected by experienced personnel, originating from selected trees chosen for their genotypical and fenotypical characteristics. In our plantations these seeds come from the region of Jicotte of Parrita. Once collected, the seeds are subjected to pregerminative treatments to accelerate and regulate their germination. Their subsequent transplantation is done in cultivated terraces, planted 20 x 20 cm. apart. The seedlings will grow for 4 to 8 months, or when the pant has at least 2 cm. in diameter. The plants are then trimmed to stumps of 10 cm. in height and 10 cm. of root and then planted.
The planting method used by our personnel is the triangular-shaped "Tresbolillo" or "Pata de Gallo". They are planted 3 meters apart, in order to obtain a density of 1111 trees per hectare. Before establishing the plantation, the terrain in prepared and cleared. Later, at three meter intervals, holes of 20 cm. deep by 20 cm. wide are dug, in which the trees are planted.
Maintenance: One month after planting, a manual clearing with machete is done one meter around each tree. Later, we fertilize with 60 grams of formula 10-30-10 or 12-24-12. During the first year, there must be two to three complete cleanings around the plantings. During the first two years the teak must be free of surrounding weeds in order to grow evenly. After the third year, cleaning is done once a year only, until such time as the crowns of the trees meet.
Management: When the plantation reaches a height of a least one meter, it is necessary to remove any suckers with a pruning shear (never machete) picking the best ones. The first pruning must be done before the trees reach a diameter of 10 cm. (2 years old on average). At this point the pruning will be half of the total height of the tree. It is done with a pruning saw (never machete). After this, there will be 2 more prunings, after thinning, at a maximum of half the total height of the tree pruning only those trees which will reach the final cutting cycle. (1,6,7)
As a complement to pruning, there is thinning. The object of this is to obtain a good quality of wood and to favor the development of the best trees. The first thinning of 50% must be done when the trees reach a median height of 8 meters, (between 3 and 5 years, depending on the quality of the site) at a time when the crowns of the trees tend to join together and there is very little undergrowth. The second intervention happens when the trees reach an average of 16 meters (between 8 to 10 years). At this point one needs to cut back 40% of the trees (Commercial thinning) in such a way to leave 300 trees per hectare for the final harvest. All these silviculture practices must be done under the supervision of a qualified forestry engineer with experience in the field. (1,2,4,6,7)
The final cut will depend on the behavior of the species in the chosen site, however on average one can expect to harvest the wood when it reaches an average of 35 cm. in diameter, with a height of approximately 20 meters.
