The infestation of bagworm larvae on sago palm (Metroxylon sagu Rottb.) applied with two types of urea fertilizer (50 to 100 kg N ha^-1), common and slow-release, in an experimental field (6 rows of 5 plots running east to west: A, B, O, C, D, and E) in Leyte, Philippines, was investigated in 2008 and 2010. The bagworm was identified as Pteroma pendula Joannis and its related species based on the appearance and the venation of the fore and hind wing of the male adult. The sago palms infested by bagworm ranged from 64 to 100 % of all sago palms from the A to the E row in the experimental field in 2008. Application of urea fertilizer, both common and slow-release, resulted in increasing, although not significant, bagworm infestation. The percentage of infested sago leaves of the spiny sago palm to total leaves of the spiny sago palm was 89 %, which was different from those of non-spiny sago palm (83 %) in 2008. In 2010, the infested sago leaves were found in the spiny sago palms only. The spiny sago palms in the E1 plot (located on the western end of row E) had 6 and 5 infested living leaves, which was 38.5 to 40.0 % of all living leaves of the sago palms. A mono-culture plantation, with limited plant species, has the same kind of pest problem and requires risk management because of the scarcity of natural enemies and the outbreak of bagworm.

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 With the aim of identifying new uses of sago starch in cooking, this starch was used as an ingredient of YATSUHASHI, substituting for part of the required rice flour (JYOSHIN and SHIRATAMA). The potential usage of sago starch was further examined by researching its effect on the physical properties and sensory attributes YATSUHASHI dough heated up in a microwave.
 When compared to SHIRATAMA flour, JYOSHIN flour was more difficult to gelatinize and resulted in a firmer and stickier gel. As the amount of substituted sago starch was increased, a harder gel was created with both JYOSHIN flour and SHIRATAMA flour. On the other hand, in regards to viscosity, when 30 % of JYOSHIN flour and 50 % of SHIRATAMA flour were substituted with sago starch, the adhesiveness significantly increased. These results suggest that, if the combined amount of rice flour and sago starch is modified, and considering that adhesiveness and hardness are the desired outcome of rice flour products, a harder and stickier rice flour product could be created.
 In regards to sensory evaluation, when 50 % or 70 % of JYOSHIN flour was replaced with sago starch, differences in color, firmness, and elasticity were discovered, and a more favorable final product was achieved. The positive effects of using sago starch in YATSUHASHI are clearly shown by these results.

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