In this paper, I have introduced the current status and outlook for the field of tree ring analysis research in Japan, including dendrochronology, dendroclimatology and environmentology. There was a time when the application of dendrochronology techniques, which are commonly used in research of tree ring analysis, was considered difficult due to the warm climate and high volume of precipitation in Japan. In recent years, there have been growing expectations for the application of these techniques, such as proposals for new concepts of dating in the area of archaeological age determination. In order to establish tree ring analysis research in Japan, it is essential that we investigate standardization functions applied to eliminating trend variations occurring with age from the tree ring time series, and functions applied to the calculation of minute variations resulting from environmental factors. In conjunction with this, the following examples have been proposed as potential projects for the future.
1)Comparative study of proposed functions. 2)Construction of a cross-check system for dated samples obtained with these techniques. 3)Verification of the contribution ratio of environmental factors contributing to auxetic growth. 4)Construction of a database for accumulating information related to tree ring disk samples, measurement data and living-tree sites.

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Intra-forest variations of wood properties (radial growth, basic density, green moisture content, heartwood color, tracheid length, dynamic Young's modulus and mechanical properties) and the difference between those of seedling forests and cutting cultivars of Hinoki (Chamaecyparis obtusa Endl.) were examined, using 60 trees of 3 seedling forests and 40 trees of 2 cutting cultivars of Nangohi. The results are as follows :
1)Intra-forest variations of radial growth of Nangohi were less than those of seedling forests.
2)Intra-forest variations of basic density at breast height, green moisture content of sapwood, tracheid length and mechanical properties of cutting cultivars were significantly less than those of seedling forests, and green moisture content of heartwood, heartwood color and dynamic Young's modulus of logs were a little less.
3)Heartwood color and tracheid length at breast height, and axial variation pattern of dynamic Young's modulus of logs differed significantly between seedling forests and cutting cultivars of Nangohi.
Thus, intra-forest variations of wood properties of cutting cultivars were significantly less than those of seedlings.

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The adsorption of six kinds of organic liquid onto dry and preswollen adsorbents, i.e., wood pulp, holocellulose and wood meal, from their dilute benzene solutions were studied as the first step of clarifying the affinity of some organic liquids for the three main constituents of wood.
The results obtained were as follows : ethanol and DMSO showed stronger affinity for dry lignin than dry cellulose or hemicellulose. Comparison of adsorption onto dry and preswollen samples, suggested that less energy is necessary for adsorption of the liquids onto dry lignin than onto dry cellulose or hemicellulose by cutting their hydrogen bonds. Liquids having relatively small molar volume such as methanol can create new adsorption sites in cellulose and hemicellulose as well as lignin without so much energy, and can then approach the sites.

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Four kinds of shear tests, i.e., JIS block, full-scale block, three-point bending and five-point bending, were conducted to predict the shear strength of the difficult to perform bending method from the shear strength of the easily performed block shear method. The results were as follows. The proportion of shear failure or combined shear and bending failure was very low in all species, especially in Japanese cedar, in the three-point bending method. In the five-point bending method, the rate of shear failure or combined shear and bending failure was just a little higher compared with the three-point bending method. In both Douglas fir and Hem-Fir, shear strength was about 40% higher for the lower limit in the five-point bending method than in the three-point bending method. The relational expression, which was calculated from the block shear and bending methods, agreed relatively well with the experimental value. The block shear method can therefore be used as a substitute for the more arduous bending method to predict shear strength. Also, as an example of estimation of shear strength by nondestructive tests, failure loads and failure modes in the three-point bending method were estimated by the equation calculated in this study and parameters of nondestructive measurement, and compared with measured values.

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This research dealt with the shearing strength properties of mortar exterior walls with wooden lath which are used for conventional wooden house. The information is needed because mortar walls detach easily from their wooden frames in severe earthquake. First we analyzed displacement and resistance to applied stresses and moments on each staple nail joint between mortar and lath. Then, in order to verify the analytical results, we performed wall racking tests on lath mortar exterior walls and examined their ductility, strength and fracture behavior.
As a result, it was proved that the proposed analysis method based on the information of joint behavior is adequate to estimate the deformation and resistance properties of the mortar exterior walls. It was also clarified that the exterior finishing materials contribute remarkably to the improvement of horizontal shear resistance of the wall, and its composition affects the strength of the wall and the damage level.

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Racking tests were conducted to clarify experimentally the structural performance of wooden frames sheathed with 9 mm-thick plywood and frames with braces 45 mm×90 mm in cross section. In the plywood sheathed frames the only failure observed of the frames was by withdrawal of nails used for installation of the plywood. On the other hand, in the braced frames many sorts of failure were observed including brace buckling. The envelopes observed on load and shear deformation angle curves showed that the braced frames had lower values than the plywood sheathed frames for stiffness, maximum load, shear deformation angle at the maximum load, the load at eighty percent of the maximum load and deformation angle corresponding to it. The multipliers calculated from the test results were 2.84 and 1.91 for the plywood sheathed frame and the braced frame, respectively. The reference shear strengths for the plywood sheathed frame and the braced frame were determined by the load at the yield point and the load derived from the structural characteristic factor, respectively. The equivalent viscose damping factors were 0.139 and 0.104 for the plywood sheathed frame and the braced frame, respectively. The ratio of tensile to compressive force in the brace was 0.719.

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Using strains of Tricholoma giganteum collected in Okinawa prefecture, the nutritional requirements for mycelial growth of T. giganteum, the most suitable sawdust medium for cultivation, and the fruit-body yield were investigated.
The results showed that the mycelial growth of T. giganteum was superior on the Hennerberg medium of synthetic liquid medium, and the GCMY(glucose, casamino acid, malt extract, and yeast extract) medium of natural liquid medium. The optimum pH value and the temperature for mycelial growth were 5.0 and 30°C, respectively. Soluble starch and mannose were the most effective carbon source for the mycelial growth and the most effective nitrogen source was potassium nitrate. On sawdust media supplemented with wheat bran, Hannoki (Alnus japonica (Thunb.) Steud.) had superior growth, whereas Mokutachibana (Ardisia sieboldii Miq.) had inferior growth. Among the 5 strains tested, the TG-12 strain had the highest fruit-body yield .

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