It is shown that the planting site has a strong effect on the growth, development and wood quality of teak plantations. The productivity of a plantation can be largely improved through the selection of a correct site for the plantation programme. It is noted that the teak distribution pattern in its natural range is of discontinuous or patchy type (Troup, 1921). Size, quality, density, and the form of teak trees varies from one location to another. There are several factors which control the distribution and growth pattern of the species. The major factors include the amount and distribution of rainfall and moisture, soil and light.
Rainfall and moisture
Teak grows naturally over a wide range of climatic condition, from the very dry (500 mm/year) to the very moist (up to 5,000 mm/year) (Seth and Khan, 1958; Kaosa-ard, 1981). Under very dry conditions, the tree is usually stunted and shrubby. Under very moist conditions, the tree is large and fluted and usually behaves like a semi-evergreen species; the wood quality is poor in terms of colour, texture and density. For the production of high quality wood with optimum growth, moisture conditions (as expressed by annual rainfall) should be between 1,200 and 2,500 mm with a marked dry season of 3-5 months (Kaosa-ard, 1981). The dry season refers to a period in which the cumulative rainfall is less than 50 mm per month (Keogh, 1987)
Teak grows best on deep, well-drained alluvial soils derived from limestone, schist, gneiss, shale (and some volcanic rocks, such as basalt. Conversely, the species performs very poorly, in terms of growth and stem form, on dry sandy soil, shallow soil (hard pan soil or lower water table soil), acidic soil (pH < 6.0) derived from laterite or peatbog, and on compacted or waterlogged soil ( Kaosa-ard, 1981; Bunyavejchewin, 1987; Srisuksai, 1991).
Teak soil is relatively fertile with high calcium (Ca), phosphorus (P), potassium (K), nitrogen (N) and organic matter (OM) contents ( Sahunalu, 1970; Kaosa-ard, 1981; Srisuksai, 1991). Several studies indicate that teak requires relatively large amounts of calcium for its growth and development, and teak has been named as a calcareous species ( Kaosa-ard, 1981; Tewari, 1992). The amount of calcium content in the soil is also used as an indicator of teak site quality. That is, the greater the proportion of teak to other associate species, the higher the calcium content in the forest soil (Bunyavejchewin, 1983, 1987).
Soil pH is another factor limiting the distribution and stand development of the species. Although the range of soil pH in teak forests is wide (5.0-8.0) (Kulkarni, 1951; Samapuddhi, 1963), the optimum pH range for better growth and quality is between 6.5-7.5 (Seth and Yadav, 1959; Kaosa-ard, 1981; Tewari 1992).
MORE INFORMATION //www.teak-teca.com/teak-photo-gallery/?album=1&gallery=1