Biodegradable plastics were applied for the effective use of sago starch-extraction residue, which has so far been treated as waste. Sago starch-extraction residue and palm oil were reacted for esterification in the presence of an acid catalyst at 160°C and 2 hours. Unreacted oil was removed to make the ester by mixing ethanol and hexane (9:1), and esterified plastics were thus obtained. Thermoplasticity of plastics, which was characterized as plastics, was added to the original (untreated) sago starch-extraction residue by esterification. Biodegradable plastics made from sago starch-extraction residue and palm oil (P-SP) were evaluated on the basis of their esterification degree according to their saponification, thermal softening point, and tensile strength. When the acid catalyst concentration increased from 0 to 1 mol l^-1 HCl, the esterification degree of P-SP tended to increase gradually. The esterification degree of P-SP, which was producing by using 1 mol l^-1 acid catalyst concentration, was 3.23 mmol g^-1. The thermal softening points of P-SP (1 mol l^-1 HCl) and the untreated sago starch-extraction residue were almost 220 and 260°C, respectively. In particular, the thermal softening point decreased down to 40°C by esterification in this study. The tensile strength value of P-SP, which ranged from 2.59 to 5.86 MPa, showed a lower value than those of commercial biodegradable plastics. It is concluded that the tensile strength of P-SP must be necessary to improve before P-SP can be used to make plant seedling pots. P-SP will be a useful biodegradable plastic for use in the manufacture of plant seedling pots in tropical areas, where sago palm and oil palm grow well.

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 On Tebing Tinggi Island, Riau, Indonesia, sago starch is no longer commonly used as a staple food; it is more common as an ingredient in cake-making. Following the traditional method of extracting the starch, the pith of two debarked logs, each ca.1 m long, was grated with a large grater. The pith was then spread on a platform covered with a nylon mesh sieve near a small river or pond and extracted by trampling it with watering. This study was conducted to clarify the starch extraction efficiency of the traditional method compared to chemical extraction. The percentage of starch extracted from the pith averaged 70.5%, which indicates that the logs were harvested at a suitable stage. The amount of starch extracted from the two logs using the traditional method averaged 32.3 kg, which was 48.0% of the chemically analyzed yield of 67.1 kg. The percentage of starch in the extracted residue was 55.7% on a dry weight basis, while the starch content of the extracted residue from the two logs averaged 35.1 kg or 52.1% of the chemically determined starch yield. Scanning electron microscope observations showed that no starch granules were present outside of the parenchyma cells of the pith after extraction, but numerous starch granules remained inside the parenchyma cells because the cell walls were still intact. On Tebing Tinggi Island, the efficiency of starch extraction from sago palm using the traditional method was about 50%. The low efficiency was attributed to incomplete grating of the pitch.

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 Rural farmers in Maluku, Eastern Indonesia, depend heavily on sago palm. They are also involved in sifting cultivation, whose main crops are vegetatively propagated crops such as taro, sweet potato, and banana, as supplementary foods. Moluccan indigenous agriculture, as referred to in this paper, consists of sago palm cultivation and vegeculture or “sago-based vegeculture.
 The objective of this paper is to examine the effect of sago-based vegeculture on the local forest landscape by analyzing the productivity of sago groves and the size of cultivated land devoted to vegeculture in Maluku.
 Based on field research carried out in a mountain village of central Seram Island, the following research findings were obtained. (1) The productivity of sago groves in the village was estimated to be 353.6-530.4 × 10 ⁴kcal ha ^-1 year^-1. This figure, which is 6 to 17 times that for upland rice fields in Kalimantan, suggests that the demand for agricultural land for sago palm is relatively small. (2) Against the background of the high dependency of the region on sago starch (the energy gained from sago starch was more than 70% of the total energy derived from staple foods), the size of cultivated land devoted to vegeculture is only 0.22ha per household; this figure is quite small in comparison to 1.4-1.8ha per household, which is the average size of millet and upland rice fields in Asia.
 The research findings reported above indicate that sago-based vegeculture, to some extent, contributes toward the preservation of natural forest of Maluku. Sago-based vegeculture appears to have effect on the local patterns of forest resources, such as the hunting of Cuscus (an arboreal marsupial inhabiting the primary forest and mature secondary forests).

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