Cocos nucifera L, the coconut palm, is an agricultural crop widely spread throughout the tropics. It has been cultivated by man for 4000 years. The main produce is copra, the dried kernel of the nut. Converted into oil, it becomes the base for a wide range of products, from cooking oil to soap and shoe polish.
Traditionally, coconut palms were found around hamlets in the tropics, in rather small stands to provide the villagers with basics such as:
At the end of the last century, coconut palms were planted in larger plantations, especially in the Pacific and on the Philippines, Ceylon, East Africa and the Caribbean, for large-scale copra production. Presently, more than 10 million ha are worldwide under coconut palms. According to stem height, tall and dwarf varieties are distinguished. 45 tall and 18 dwarf varieties are known. All older plantations are planted with tall varieties. Once these palms are 50 – 60 years old the copra yield declines rapidly. When the plantation-grown palms reached this age in the 1960s, replanting programmes were developed and the question of economic removal and disposal of old palms arose.
Removal was necessary in order to make space for new plantations. If the material was left to rot, the rhinoceros beetle (Oryctes rhinoceros) would start to breed in the decaying material and attack the young seedlings. Subsequently, various coconut-growing countries started to investigate the economic disposal or use of the stem. The research activities started were partly funded and backed by the governments of New Zealand and the Philippines, as well as by the FAO (Food and Agriculture Organization of the United Nations). In Zamboanga, Philip-pines, a research station was established and the utilization of the coconut palm stem as a timber resource was assessed and proven.
Properties of the palm stem
Although inappropriate, the term “coconut wood” has been established for the material of the coconut palm stem, and will therefore be used in this handbook as well. Unlike “conventional” trees, palms, like many other monocotyledons, have vascular fibre bundles (red-brown spots on a cross-section) scattered in a yellowish parenchymatic ground tissue. These bundles contain the water and nutrient transport system (xylem vessels and phloem) as well as thick-walled fibres giving the stem its strength, and paratracheal parenchymatic cells. The ground parenchyma has mainly a storage function and contains starch among other things. The anatomical features result in a rather non-homogenous distribution of physical properties both over cross-section and height, and thus in a very non-homogenous raw material. Principally, the density decreases towards the centre of the stem, and over stem height. Figure 1 gives a qualitative impression of the density distribution over the stem from five 80-year-old Philippine palms, Photo 1 shows its distribution (dark = high density) over a cross section.
Sources FAO Report, Assessed on 21 February 2016
Traditionally, coconut palms were found around hamlets in the tropics, in rather small stands to provide the villagers with basics such as:
- vegetable fat (from copra)
- roofing material (leaves)
- ropes and strings (coir from the husks)
- beverage (coconut juice)
- alcoholic drink (from the inflorescence - tuba or toddy)
- fuel (from the husks and nuts)
- timber (from the stem).
Removal was necessary in order to make space for new plantations. If the material was left to rot, the rhinoceros beetle (Oryctes rhinoceros) would start to breed in the decaying material and attack the young seedlings. Subsequently, various coconut-growing countries started to investigate the economic disposal or use of the stem. The research activities started were partly funded and backed by the governments of New Zealand and the Philippines, as well as by the FAO (Food and Agriculture Organization of the United Nations). In Zamboanga, Philip-pines, a research station was established and the utilization of the coconut palm stem as a timber resource was assessed and proven.
Properties of the palm stem
Although inappropriate, the term “coconut wood” has been established for the material of the coconut palm stem, and will therefore be used in this handbook as well. Unlike “conventional” trees, palms, like many other monocotyledons, have vascular fibre bundles (red-brown spots on a cross-section) scattered in a yellowish parenchymatic ground tissue. These bundles contain the water and nutrient transport system (xylem vessels and phloem) as well as thick-walled fibres giving the stem its strength, and paratracheal parenchymatic cells. The ground parenchyma has mainly a storage function and contains starch among other things. The anatomical features result in a rather non-homogenous distribution of physical properties both over cross-section and height, and thus in a very non-homogenous raw material. Principally, the density decreases towards the centre of the stem, and over stem height. Figure 1 gives a qualitative impression of the density distribution over the stem from five 80-year-old Philippine palms, Photo 1 shows its distribution (dark = high density) over a cross section.
Fig. 1: Schematic density distribution in mature coconut palm stem
Source: Killmann, 1983
Sources FAO Report, Assessed on 21 February 2016
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