Tropical peat soils in South East Asia are mostly oligotrophic, and some are mesotrophic according to the classification by Coulter (1957). The sago palm is exploited as a staple and cash crop in Sarawak, Malaysia. It is a perennial starch crop of some economic importance in Sarawak, and has adapted well to peat swamp areas. However, it is said that sago palms growing in deep peat soils take a longer time to reach maturity than those in shallow and alluvial soils. The differnces in growth rates of sago palms related to the types of soils are discussed.
 The comparison of growth rates of the sago palm grown in deep and shallow peat soils was studied in Sungai Talau Peat Research Station, Dalat, Sarawak, Malaysia. Growth of sago palms in deep peat soils and shallow peat soils was measured in terms of several growth parameters, and growth rate data obtained in 1992, 1993, 1994 and 1995 were compared.
 There were considerable variations among sago palms in deep peat soil when the trunks emerged from the ground. It took 5-6 years after planting of suckers for the trunk to form. The frond emergence rate differed year by year, ranging from 17 in the initial 3 to 4 years to 19.2 after trunk formation to 12 in the following years. Based on the total number of fronds, the trunk formation periods to be 7-9 years, based on the total number of fronds, the entire maturation period of the sago palm in deep peat soil amounted to 12 to 15 years after planting, revealing that sago palms in deep peat soil have significantly shoter and fewer fronds than those in shallow peat soil. The canopy of sago palms in deep peat soil was not well developed. Therefore, growth of the sago palm in deep peat soil is slower than in shallow peat soil. To compensate for the inferiority of the sago palm in deep peat soil, further investigations are required such as finding new species which reach maturity more rapidly and have higher starch content.

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 It has recently become evident that plastics derived from petroleum have accumulated in the natural environment and seriously affected ecosystems. This has led to the desire for the development of degradable plastics. Sago palms are planted as a food resource in Southeast Asia because they have a lot of starch in their pith. Because of their component characteristics, they could be a good raw-material for biodegradable plastics. This paper describes an attempt at thermoplasticization of the sago palm with some chemical modification.
 A chemical component analysis was conducted with a view to utilizing the sago palm as a new woody resource. The components of sago palm were affected by soil characteristics. In particular, the starch contents varied with soil type and growth stage. Thermoplasticization of the sago palm was done by acetylation, which is an esterification method. Thermoplasticity after acetylation was evaluated by making sheets on an experimental basis by hot-pressing acetylated materials. Furthermore, the thermal behavior of these sheets was determined by thermogravimetry analysis (TG) and thermomechanical analysis (TMA). The sample with the lower starch content showed higher acetyl content. The sheets made by hot-pressing showed thermoplasticity at 180℃, and thermal softening point of the sheet made from sago growing in peat soil appeared at about 150℃. It was suggested that thermoplasticity of sago palm could be achieved by chemical modification. As a result, it was also suggested that biodegradable plastics could be produced from the sago palm.

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