Infestation of the invasive dry-wood termite, Incisitermes minor (Hagen) was first reported in Japan in 1976 at a residential house in Tokyo. Since then, records of I.minor have steadily increased, and more than half of the prefectures in Japan are listed as infested areas at present. The integrated management of I.minor consists of two phases: the individual technological phase and the regional phase. Recent research efforts have been overcoming the technological issues, and the regional systematization of management system will be the next target. The development of novel preventive/remedial strategies against I.minor may have a positive effect on the wood preservation industry in Japan.

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Early in the 1950s, slash pine (Pinus elliottii) was introduced into Japan as an exotic species for plantation. Growth characteristics of slash pine planted in Japan were studied and it was reported that slash pine had superior growth rate and resistance to diseases as compared to domestic pine species. However, few studies examined the characteristics of annual ring formation and the variations of wood properties of slash pine grown in Japan. In this study, we examined annual ring formation and wood properties of 46-year-old slash pine grown in southern Kyushu, Japan. Based on obtained results, we evaluated the usability of slash pine as an exotic species for plantation in Japan. In slash pine, cell division during latewood formation was more active than in sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa). Furthermore, it was assumed that the characteristics of annual ring formation produced higher basic density in spite of superior growth rate. Basic density and mechanical properties in bending of slash pine grown in southern Kyushu were the same as those of slash pine grown in North America. In slash pine with faster growth rate, it was shown from the radial variation of microfibril angle of the S₂ layer in the cell wall of latewood tracheids and latewood tracheid length that the transition from juvenile to mature wood occurred at an earlier ring number and there was less variation in mature wood. From the obtained results, it was assumed that slash pine plantations could produce wood with superior mechanical properties more efficiently than sugi plantations in Japan, because of the faster growth rate and few negative effects of the faster growth rate on wood properties.

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Much driftwood appears on rivers, dams, and at the coast after natural disasters such as heavy rain and typhoons. Driftwood is usually considered a nuisance because of decreasing capacity of dams and disturbance of sea routes. Therefore, it is gathered and disposed of as industrial wastes. However, they are natural bioresources and have a potential for utilization as wood products. In this study, the properties of driftwood salvaged from dams and the sea were evaluated by an elementary analysis using SEM-EDXA method. The results showed that inorganic substances in driftwood from dams were distributed on the end surface of logs and the circumference of driftwood. This means that it is difficult for inorganic substances to move inside of driftwood without a fracture pathway. On the other hand, chlorine in logs immersed in seawater was distributed throughout the sapwood after eight weeks. In heartwood, the distribution of chlorine spread gradually for four weeks and didn't change after that.

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The decay durability of the sapwood and heartwood of sugi (Cryptomeria japonica), hinoki (Chamaecyparis obtusa), akamatsu (Pinus densiflora) and konara (Quercus serrata), and the sapwood of buna (Fagus crenata) grown in Shimane Prefecture was examined according to the JIS (JIS Z 2101 (1994)) using the brown-rot fungus, Fomitopsis palustris, and the white-rot fungus, Trametes versicolor. In addition, wood samples of these species, square pillar-shaped, were provided to measure the propagation velocity of ultrasonic waves and to test the partial compression strength after decay treatments with F. palustris and T.versicolor. After decay treatment of the wood samples, values of 3.2% to 12.9% mass loss were recorded for the sapwood of all species and the heartwood of akamatsu when testing with F. palustris. The propagation velocities of ultrasonic waves along with the thickness directions for decayed-wood samples decreased most in the vicinity of the cross section directly contacting the culture medium during the decay test. Further, the partial compression strengths of σ_e5% and σ_e10% (at 5% and 10% deformations of the sample thickness, respectively) for the decayed-wood samples also decreased. The ratios of σ_e5% and σ_e10% to the control were 0.36 to 0.85 in the test with F.palustris. For the decayed-wood samples, statistically significant (P < 0.01) negative correlations were recognized between the decrease of propagation velocity of ultrasonic waves and the remaining strength of σ_e5%.

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The aim was to investigate the extent of reduction of ammonia emissions from poultry manure by utilizing cedar bark, which occurs plentifully from timber trimming facilities and has an ability to adsorb ammonia. In a laboratory scale study, cedar bark meal was contacted with an ammonia concentration of 620ppm in Tedlar bags for 5minutes. The result showed that the bark reduced ammonia by 99.5%. This study compiled data on ammonia above poultry manure covered with cedar saw dust or cedar bark during a period of 3 weeks. The results indicated that both types of covering agents achieved significant reductions in ammonia concentrations. The adsorption of ammonia was 11mg·g^-1 and 33mg·g^-1 for saw dust and bark respectively. Water-soluble nitrogen, ionic nitrogen, and organic nitrogen accounted for 22%, 23% and 47%, respectively, of increased nitrogen in the bark during composting. It suggested that the increase in ionic nitrogen was due to the higher cation exchange capacity. The increase in organic nitrogen may be attributed to covalent bonds. The results showed that the reduction in the emission of ammonia appears to be caused by the bark cover acting as an inexpensive and simple deodorizer.

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