The number of high efficient forest machines has increased greatly in Japan in the 1990's. But it is pointed out that there are a lot of problems in the efficient operation of the machines. To clarify the actual condition and the problem of the use of high efficient forest machines, we sent out questionnaires on the use of high efficient forest machines to users (109 log production dealers) in the Kansai district in December, 1997 (response rate: 53%). 90 percent of users answered, "The machine can be used". But it was clarified that there were problems such as low spur road density in forest and lack of wood yard or working area for machines in forest, and that it was a big problem to secure the amount of log production to operate the machines efficiently. In order to use high efficient forest machines efficiently, it is necessary to change the log production system by individual forest owners' decision-making into that based on the regional logging plan.

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Forestry sector in Japan has been suffering from diminishing labor force and their aging. However in recent years, some enterprises were successfully acquiring young workers from both rural and urban areas. This paper introduced a case study of Ichinomiya Town Forestry Cooperative. At the beginning of 1980 s, in order to recruit the young forestry workers, this Cooperative introduced the 'Gengyo-Shokuin' Institution which was mainly characterized by both the monthly payment and a raise of the wage base system in a wage system. As a result, it has been known as one of the most advanced Cooperatives because of its successful pioneer countermeasure to deal with acquiring the forestry workers. But in these days, expense for salary of workers is getting larger from year to year, and it is suppressing the management conditions of the Cooperative. To solve this difficult problem, Ichinomiya Town Forestry Cooperative introduced the 'Shinrin-Gijutsuin' Institution for the new employment after 1993. The content of this institution is that in a wage system; for the first 5 years Cooperative adopted the monthly payment system; from 6th year, it-pays wages in the piecework payment system. Lastly, the author gave a brief summary about present situation of countermeasure for recruiting young forestry workers in this successful pioneer forestry sector.

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Lumber for musical instrument needs high quality for beautiful sound. This paper examines lumber for piano, because piano are mass-produced in Japan, and focus on the material for piano soundboards. In Japan, large-scale piano production was started after World War II. Especially, piano production has increased since 1960, stable lumber supply was necessary for piano companies. At that time, Yezo spruce (Picea jezoensis) was generally used for piano soundboards in Japan, but its resources and cut down quantity had been decreasing. In 1961 lumber import was liberalized, and piano companies had substituted Sitka spruce (Picea sitchensis) for Yezo spruce. Today, Sitka spruce is main material for piano soundboards because of stable supply. However Yezo spruce has been used and in recent years, use of European spruce and Chinese spruce has started. Piano companies use lumber of different grade for degree of piano production because they aim for wide users.

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At the Earth Summit in 1992, the United Nations Framework Convention on Climate Change (UNFCCC) was signed, and at the Third Conference of the Parties to the Framework Convention on Climate Change (COP3) held in Kyoto to follow up the Earth Summit, the Kyoto Protocol was adopted. A provision of the Protocol is to include the sources and removal of carbon dioxide by forests as a measure of the increase and decrease of greenhouse gasses. In this study, we traced the changes in the forest stock, and calculated the carbon flow in each sector of sawn timber, paper/pulp, and plywood. The calculation data for 1979 and 1991, which included the contents of the woody residues, was used. During this period, the forest stock was increased because of import of wood to compensate for the shortage of domestic wood products, and because of the conversion of broad-leaved forests to more productive coniferous forests. The carbon flow to the stock for building houses increased, while the amount of woody residues decreased in the sawn timber sector. In the plywood sector, the amount of woody residues also decreased because of declining domestic production. The amount of waste paper and paper dust increased together with consumption in the paper/pulp sector. Summing up the three sectors, the amount of total carbon flow increased in the forest sector from 1979 to 1991, the paper/pulp sector of which occupied about 80% of carbon emission.

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Rural-tourism is a type of regional promotion employed to make good use of the natural environment, agriculture, forestry and rural culture in mountain villages. In Kita village, rural-tourism is promoted by the village organization to protect thatched roofs. This study examined the village organization of Kita, and analyzed beneficial factors and effects of the village organization for regional promotion. Kita village is a reserve area designated by the Agency for Cultural Affairs. Thatched roofs are protected and many tourists visit this area. The village organization operates a tourist home, restaurant and a museum of folk customs, the construction of which was subsidized. The main factor that has allowed the village organization to succeed is a partnership between the local people and the readers. This regional operation was initially started with administrative guidance, but currently, the village organization acts voluntarily by regenerating the village character, community life and mutual aids. The village organization is self-governing. Consequently, changes in the village society resulted in effective regional promotion.

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MINAKATA Kumagusu (1867-1941) is known as a naturalist. His achievements in the field of biology, ethnology and so on are famous world-wide. Recently, his thoughts are attracting attention with the rising concern about environmental problems because he opposed the government's policy to abolish and amalgamate shrines, and led the movement to protect the shrines and shrine forests around 1910. At present, it is said that his movement was based on his unique point of view of uniting nature and human life because he used the word 'ecology', and his thoughts on environmental conservation had already achieved modern standards at that time. But his logic was only that the abolishment of 'shrines', would cause collapse of customs and traditions of local society, and that by cutting 'shrine forests', all creatures living there would be exterminated. Thus, in his thoughts 'shrine' and 'shrine forests' were separated. About the relationship of nature and human life, his logic was only a reflection of that of other persons of his time, and he just used the word 'ecology', which was being used abroad, in the sense of studying ecology, only as the grounds to protect shrine forests.

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National parks in U. S. A. are kept by USDI National Park Service and many people who take part in the volunteer activities every year. Volunteer activities are managed by the USDI National Park Service and many cooporative associations. The volunteers are doing activities making a choice among many kinds of activities. They are supported by USDI National Park Service with food,clothing,and shelter and securities for the activities. The volunteers are increasing year by year. However.the programs had to reduce of scale and decline of qualities by the infruence of budget cut in National Park System, under the Clinton Administration's reconstruction of finance. Under this situation the cooporative associations, supporting for national parks, have forced to be active in their association and extend of it to keep the programs. And thus, the cooporative associations has come to take more part of management of national parks. This paper made clear the progress of cooporative associations, and paid attention to relationships between the USDI National Park Service and the cooporative associations (NPO) supported by individual and enterprises, based on the survey materials about the volunteer in parks systems made by USDI National Park Service and the cooporative associations.

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The purpose of this study is to analyze the conscious structure of the amenity of a local forest park at Sinji town in Shimane prefecture using AHP (Analytic Hierarchy Process) method by a pair comparison questionnaire interview survey about the park visitors and park administers. The whole amenity of forest park is classified into 2 categories such as amenity from park forest itself and amenity from park facilities. The amenity from park forest itself is classified into 5 categories such as the sense of sight, the sense of taste, the sense of hearing, the sense of smell, the. sense of touch and the sense of taste. The amenity from park facilities are clasified into 4 categorilies; sports, accommodations, studying and observation. According to the results of the analysis for all samples, the ratio of the amenity from forest own was 73.6% and that from park facilities was 26.4%. The ratio of the amenity from five senses were as follows: sight 43.5%, taste 8.9%, smell 14.9%, touch 15.5% and taste 7.2%. These results can therefore furnish more effective information for the management or planning about the local forest parks.

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Recently, hay fever has been one of the problems widely discussed in the society. While Cryptomeria japonica is regarded as one of the causes of hay fever, it is an important tree species because it glows up fast, and is useful for timber. This report shows to what extent the public suffer from hay fever and what opinions they have about forest and Cryptomeria japonica management. The information for this research was obtained through questionnaires, and answers from one area were compared with those from another area in analysis. The ratio of hay fever patients was less than 20%. It is widely recognized that not only pollen of Cryptomeria japonica but also other factors are concerned with hay fever. In general the public are in favour of Cryptomeria japonica forest because of its important role in forestry, however, the majority of them want the present species replaced by another one with less pollen. It is our task for the future how we incorporate the public opinions in the forest management of Cryptomeria japonica, which is the cause of hay fever and an important species in forestry.

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As a trial of field-oriented studies for sustainable forest management, a forest monitoring project started in Hokkaido (Ishikari-Sorachi forest planning unit) and Kochi (Shimantogawa forest planning unit) from 1996 to 2005. It aims to search some suitable criteria and indicators for field level implementation in those excellent case studies of River-basin Forest Management System. This project is entrusted to two local governments under the sponsorship of Forestry Agency in cooperation with national forest institutes and regional forestry offices. At the first year, a basic design of this project was discussed. In the Montreal Process, seven criteria and 67 indicators in national level were already agreed. According to these indicators, we started to assemble and compile field level data. In this paper, a basic design and the guidelines are discussed in Kochi Prefecture or regional level.

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In 1996, actual conditions of log production were examined in Shimane Prefecture, Japan. There were 365 units of logging contractors and 245 units of them were in logging operation. Only 38 units of logging contractors were operating their own sawmills individually. The total volume of annual log production was 420,000m3, and hardwood and pine wood occupied by 79 % of all the log production and Japanese cedar and Japanese cypress woods by 21%. Log Production made by the forest owner's cooperatives amunted to only 7% of all in volume. The average log production of one unit of logging contractors was 1,714m^3 per year. One employee produced averagely 2.07m^3 per day. The total numbers of employees was 1,043 persons and 80% of them were of full-time employment. The employees who were below 40 years old were occupied by 11%, though those who were above 60 years old occupied by 42%. A larege number of employees held licences for logging operation machines such as chain-saw.

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The procedure of retrieving a suitable range of the yarding with tower yarder is discussed by using GIS for 290 subcompartments in the Prefectural forest of Kigima. The distribution maps of the forest resources, the slope, and the arrival distance was made by GIS in this stand respectively. The retrieved subcompartments for the yarding by tower yarder is a part of sugi (cryptomeria japonica), hinoki (chamaecyparis obtusa) and the mixed forest [128 subcompartments] referenced to in the tree species, and is a part of 33-55% [88 subcompartments] to the slope, and is a part of 0-150m [153 subcompartments] to the arrival distance. The result of retrieving subcompartments which satisfies three criteria became about 10% of the whole [31 subcompartments].

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We examined the way of estimating the thinning effect using the mesh method in conventional non-line thinning and line thinning to utilize the high-performance yarding machine. The effect of line thinning was a little less than non-line thinning. However, it found that the effect like a non-line thinning was gotten by cutting additional few neighbor trees around the thinning lines. The work efficiency is high, and line thinning has the merit that it is possible to use the line trace, when the next thinning and tending would be done.

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The plate type greening devices originally developed by Okayama Prefecture Forest Experiment Station (Nishiyama 1997) were applied in May and April 1995 on a gully site after the large-scale forest fire in August 1994 at Mt. Ouji in Tamano, southern part of Okayama Prefecture. Two study plots with 100m^2 in size were set up and examined conditions of vegetation recovery after the forest fire. Pteridium aquilinum on a slope facing the northeast grew better than on a slope facing the southeast. Both wild seedlings of Paulownia tomentosa, Alnus sieboldiana and Cytisus scoparius, and seedlings of Paulownia tomentosa, Prunus jamasakra and Castanea crenata on the plate type greening devices grew better than Pteridium aquilinum. These species had effect of controling development of Pteridium aquilinum. Survival rates of three species on the plate type greening devices after three growing periods were more than 60%. These results suggested that application of Paulownia tomentosa, Prunus jamasakura, Castanea crenata in addition to Alnus sieboldiana and Cytisus scoparius as established species for erosion control is effective for an early greening project at a site after a forest fire.

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Nitrogen cycling in seasonal tropical forest soil was studied. Several forms of carbon and nitrogen pools in soil were determined. Total C, N and C/N ratio ranged 45.5〜94.3ton ha^<-1>, 2.2〜5.8ton ha^<-1> and 17〜22 respectively. They were almost same as Japan. Extractable C and soil microbial biomass C (SMB-C) were smaller than in Japan. It is considered due to no organic materials accumulation on the forest floor. Extractable N, SMB-N and inorganic N ranged 60〜243 mg N kg^<-1>, 70.6〜391.8 mg N kg^<-1> and 8.1〜64.8 mg N kg^<-1>. All concentrations of C and N were highest in the surface soil and decreased sharply with depth. It coincided with the distributions of fine root. However, inorganic N occupied more than 51% of extractable N. It was suggested that there might be additional mechanisms for keeping N in the system other than plant uptake.

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We set study sites in two Siamese forests in order to investigate the chemical properties and nutrient accumulation in soil systems. One is established in Sakaerat, and another is in Kog Ma. Total carbon and nitrogen, soil pH in water and in KC1, exchangeable minerals and cation exchange capacity (CEC) were measured. Soil pH(H_2O) was ranging from 4.1 in forest floor of Sakaerat to 5.4 in deep soil of Kog Ma. Soil pH(KCl) was ranging from 3.6 to 4.5. The ΔpH were -0.4 to -0.6 in organic layer and -0.6 to -1.0 in mineral soil layer. Sakaerat soil contained less organic matter than Kog Ma soil. The sum of cations varied from 0.2 to 1.7 cmol(+)kg^<-1>. The CEC was low in Sakaerat and high in Kog Ma. Upper soil of Sakaerat had CEC of less than 10 cmol(+)kg^<-1>, but upper soil of Kog Ma had CEC of more than 20. Base saturation rate was about 10% in Sakaerat soil and 1 to 7% in Kog Ma soil.

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The spectroscopic properties of fluorescent substances in soil solutions, ground waters, spring and stream in a forest catchment were investigated by three dimensional excitation emission matrix spectroscopy. The fluorescent substances detected were suggested to be the substances similar to fulvic acid. The fluorescence characteristics of soil solutions were different among the location of slope or soil depth. Relative fluorescence intensities of soil solutions at middle slope decreased down through soil and the spectroscopic properties of those were different among each soil depth. The spectroscopic properties in ground waters at the unsaturated type wells were similar to those of soil solutions in the surface soil at upper and middle slopes. So, it was confirmed that ground waters at the unsaturated type wells occurred by movement of soil solution, temporal saturated lateral flow. The spectroscopic properties were different between ground waters at saturated type wells and soil solutions. For ground waters at saturated type wells, spring and stream, clear peak of fluorescent substances was not detected. The spectroscopic properties of water samples" in this catchment were classified into three categories. The categories may be corresponded with the spatial distribution of humic substances. It was showed that the three dimensional excitation emission matrix spectroscopy was useful for analysis of dissolved organic carbon in forest catchments.

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A methodological survey was carried out on the effect of nutrient media and incubation period on the structure and diversity of mycobiota on beech leaf litter. Sample leaves of beech (Fagus crenata Blume) used for isolation of fungi were collected in September 1997, at Ashiu Experimental Forest of Kyoto University. The leaf samples were incubated using both nutrient poor (_<LC>A) and nutrient rich (PDA) media. Fungi isolated from the samples were tested their growth rates on _<LC>A and PDA. Significantly larger numbers of species were obtained using _<LC>A than PDA. On PDA, fungi of higher growth rates were selectively isolated. Relationships between incubation periods and number of species were examined. Nearly 80 to 90% of species were isolated in five weeks of incubation. Therefore, it was concluded that the incubation of the nutrient poor medium (_<LC>A) for two months was useful for the description of mycobiota on beech leaf litter.

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Seasonal change in soil respiration rates, litter fall rates, fine root biomass and environmental factors were investigated at the upper, middle, and lower part of a slope which showed different site quality (different aboveground growth). At these plots in a 30 year-old Japanese cedar (Cryptomeria japonica) plantation, the soil respiration rates increased exponentially with increasing soil temperature, and this relation could be approximately expressed by the following equation: y=a exp(bx) (y: soil respiration rates, x: soil temperature, a, b: constant). The annual soil respiration rates from Sep. 1997 were estimated ll.5, 13.4, and 6.4 (tC/ha/yr) at the upper,middle, and lower plot, respectively. The root respiration rates were estimated by the differences between that in the trenched area where the roots were severed and in the control. The root respiration rates were 2.7, 2.0, 1.8 (tC/ha/yr), and the litter fall rates were 3.2, 3.9, 4.0 (t/ha/yr) at the upper, middle, and lower plot, respectively. Assuming that the storage of soil organic matter is in a steady state, soil respiration could be approximated by the sum of aboveground litter decomposion, belowground litter decomposion, and root respiration. Substitution of the values estimated above enables one to calculate the component ratios of the agents respiring in soil. These results indicate that, at the lower plot where soil moisture condition was preferable and less fine root biomass was found, aboveground litter decomposion and root respiration contributed more than at the other two plots.

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We have measured sulfate and nitrate (SO_4^<2->, NO_3^<->) concentration in precipitation, through fall, and stem flow at the Hinoki stands in Shikoku Research Center, Forestry and Forest Products Research Institute in Kochi City since April 1991. In this paper, we discussed the variations of annual loads of SO_4^<2-> and NO_3^<-> calculated from the concentration and the amount of precipitation, through fall, and stem flow from 1991 to 1997, to obtain the fundamental information on the effect of the acidic deposition to forest ecosystems. The annual SO_4^<2-> loads of precipitation, through fall, and stem flow were 2.63〜4.40, 3.13〜4.93, and 1.13〜1.70g m^<-2>, respectively. On the other hand, the annual NO_3^<-> loads of precipitation, through fall, and stem flow were 1.02〜1.94, 1.20〜2.08, and 0.16〜0.45g m^<-2>, respectively. These variations of annual loads were considered to be affected by the amount of annual precipitation, through fall and stem flow. Summation of the loads of through fall and stem flow, indicating the loads on forest soil, reached 4.26〜6.31g m^<-2> in SO_4^<2-> and 1.36〜2.85g m^<-2> in NO_3^<->, respectively. The SO_4^<2-> loads increased by the flow processes of rain water through the forest canopy, whereas the NO_3^<-> did not increase.

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The aim of this study is to organize the techniques for long term forest management and put the vanishing technique on record by examining the existing technique in Yoshino. We obtained by hearing the criteria of thinning tree selection and Mr. Tadakazu Arizuka's autobiography who is one of 'Yamamori' forester working at sugi and hinoki plantation at Sugitani in Higashiyoshino. As the results, it is clear that he found fun and something to work for and was responsible for his work. He learned about some of techniques by his leaders and he kept working for a long time. His criteria of thinning tree selection are; 1. 'To keep good tree formation. (He would like to keep forest high quality.) 2. To watch the tree canopy. (By doing so, he decides which tree is to be thinned.) 3. To cut the tree standing at the upper side of the hill. (Such trees will disturb the growth of ones standing at lower.)

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The characteristics of thinning tree selection applied by Mr. Tadakazu Arizuka was analyzed at Sugitani in Higashiyoshino. We selected some thinning trees setting for further long-term management. Before and after the selection, we measured the DBH of all individuals. In spite of applying the same criteria in selection of thinning trees, the way of thinning selection was different between older forests (about 50-120 years) and younger forests (about 17-45 years). The management system of Sugitani plots corresponded to the Yoshino's thinning selection methods in middle intensity. We compared the Yoshino thinning selection in middle intensity with that of. Wakayama by growth ring distribution. It was appeared that Yoshino thinning selection system was able to keep the width of ring growth constant.

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The number of trees remaining and the situation of damage occurring by brush cutting were examined in artificial forests of Fagas-crenata and Aesculs-turbina (9-year forests). The number of Fagas crenata and Aesculs turbinata , had decreased 30-50% during the 9-year period after planting. This was much higher than the 5% decrease in the number of Cryptomeria japonica and Chamaecyparis obtusa. The damage occurring in the forest of Fagas crenata and Aesculs turbinata was mostly caused by brush cutting, herbivoes, and insects. Brush cutting caused as much as 40-70% of the damage. The average plant height of the non-damaged trees of Fagas crenata (130cm) and Aesculs turbinata (180cm) was much higher than that of the damaged trees, which were 40 and 70cm in height respectively. Most of the damaged trees were covered by shrubs and herbs (100cm in height). The trees showed death of the main axis or damage by herbivores followed by regrowth.

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An ordination of 12 isolated broad-leaved evergeen forests in the southern part of Kyoto Prefecture was made using a correspondence analysis (CA) based on data on presence/absence of 163 vascular plants. These data were obtained by a vegetation analysis using the belt transect method. Three environmental factors regarded as being related to forest isolation were considered: forest area, ratio of perimeter of the forest to perimeter of the circle having the same area, and distance from the Mt. Kasuga, Nara Prefecture, whose forest is a large-scale primary forest and so might be a seed source. It is discussed in this paper how much these factors account for the results of the CA. The site score of the first axis of the CA showed a statistically significant correlation with forest area. This correlation showed a possibility that the species component of forests studied might have been influenced by the forest area. The site score of the second axis showed a discrete distribution. Though the score of the second axis showed a statistically significant correlation with the distance form Mt. Kasuga, it might be reflected the change of species component with location, rather than the distance from the seed source. This is because the species components of studied forests were quite different from that of the Mt. Kasuga area.

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The size structure of 11 year-old Liquidambar formosana dense plantations were studied and their standing biomass were estimated. Initial stand densities were 10,000 and 40,000 trees per hectare, respectively. The average values of diameter at ground level and height estimates as well as basal area were, 7.4cm, 9.3m and 45.2 m^2/ha in lower density stand, and 4.4cm, 8.4m and 66.7 m^2/ha in higher density stand. The less dense stand had higher canopy layer position but there was no clear difference in canopy layer depth between stands. The standing biomass of each organ, i.e. stem, branch and leaf estimated with using allometric relationships was 45.3, 3.1 and 2.3 (ton/ha) for 10,000 trees/ha stand, and 61.9, 3.6 and 2.8 for 40,000 trees/ha stand, respectively. The mortality was low in both stands so that 96 % of planted trees were survived after 11 years. The density effect was abserved in tree sizes, however, natural thinning did not take place yet.

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The seed fall of 8 tree species in 12 broad-leaved tree seed collection forest stands was surveyed using a seed trap from 1992 to 1998. In some years Fagus crenata, Quercus crispula, Zelkova serrata, Prunus grayana, Castanea crenata and Juglans sieboldiana hardly produced seeds. The former four species showed alternate bearing. The seed fall per m^2 for a good crop year was about 150-300, 100, 500-3000, 750, 30-60 and 10-20, respectively. Aesculus turbinata and Prunus jamasakura produced seed similarly in all years surveyed with a mean seed fall of 880 and 40, respectively. There was a negative correlation between the mean seed weight and the maximum seed fall in the 12 stands. This indicated that the number of seed per crown area had an upper limit regardless of the species.

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Trichoderma sp was detected as a dominant species in contaminated culture of Lyophyllum shimeji buried in the soil of forest floor. Propagation of microorganisms was inhibited in the soil baked more than 400℃. The baked soil was used for burying and surrounding the colonized substrate of L. shimeji to facilitate to form mycorrhiza. It was revealed that this method was effective in protection of the inoculum against microbial contamination in the soil and showed the same effectiveness as a method using a fungicide, 'benomil'.

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To find out the best substrate for growing fruit-bodies of Hatakeshimeji mushroom, Lyophyllum decastes, the formulation of ingredients was investigatied using sawdust from Sugi, Cryptpmeria japonica, piled outdoor with occasional watering, Kanumatsuchi for gardening soil, corncob meal, malt feed and wheat-bran. 1. As additional quantity of Kanumatuchi increased, pH of the substrate rose up and the period for mycerlial colonization shortened and the yield of nomal-shaped fruitbodies increased. 2. As additional quantity of wheat-bran increased, the period for mycelial colonization was lengthened and the yield of normal-shaped fruit-bodies deceased. 3. The mixture of 5L of Sugi saw-dust, 1L of wheat-bran, 2L of Kanumatsuti, 1.5L of malt feed and 2L of corncob meal was the best formula as substrate for growing fruit-bodies in this study. 4. Sugi saw-dust piled outdoor for three months retarded mycelial run because of inhibitors remained in the saw-dust and caused growing of abnormal fruit-bodies.

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Crossbreeding and tissue culture of cherry tree were studied. Adventitious buds of a protected variety of cherry tree called Sikizakura'from Katuyama City were cultured for 60 days. After a small callus formed on the leaves and stems, leaf segments were suspension cultured in lmL MS liquid medium to try to regenerate the plants. The medium was augmented with one of the following combinations: NAA and IBA, IAA and IBA, IAA and BA, 2,4-D and BA, or 2,4-D and IBA. The cultures were maintained in the dark at 24℃. Very little callus formed under a wide range of hormone conditions. Adventitious root developed from callus with a high concentration of NAA, but the leaf segments withered with the other combinations.The calluses were also suspension cultured in MS liquid medium with different light conditions, and concentrations of medium and sugar for 60 days, without effect. A different species of cherry tree, Gyoiko・(Prunus lannesiana cv. ascendens) from Tessei City, was examined. Leaf segments were cultured on MS agar medium with 100uM NAA. In this case, a large callus formed on the leaf cross-section and adventitious roots developed after 7 days. A small callus was formed when a third cherry, Daigozakura・(Prunus pendula form, ascendens) from Ochiai City, was cultured, but it withered. No adventitious buds developed in any case.

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Effects of two support materials (agar and Florialite) and two carbon sources (CO_2 and sucrose) were examined on the rooting of the shoot cultures of Hinoki (Chamaecyparis obtusa) and Kunugi (Quercus acutissima). Rooting rate of Hinoki (C. obtusa) on the agar was larger than that on the Florialite, however, it was reversed for Kunugi (Q. acutissima). Root quantities shown by root length per shoot of Hinoki (C. obtusa) or dry weight of root of Kunugi (Q. acutissima) on the Florialite were smaller than those on the agar. However, growth rates of Hinoki (C. obtusa) and Kunugi (Q. acutissima) were better on the Florialite. Rooting rates and root quantities were promoted by addition of sucrose (2% cone). Hinoki (C. obtusa) could grow autotrophically under CO2 enrichment. Effect of CO_2 enrichment on the growth of Kunugi (Q. acutissima) was smaller under low illuminance.

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In order to define whether larvae of the Japanese pine sawyer are responsive to photoperiod in their pupal chambers in pine bolts, beetle infested bolts were debarked to remove larvae remaining under bark and maintained at 25℃, LD0:24, LD10:14 and LD16:8 for five months from 20 November or 22 December, 1997. For those bolts kept at 25℃ from 20 November, emergence rates of the beetle differed with photoperiod, with 51.7, 26.7 and 95.8% emergence, respectively. A possible response to photoperiod by larvae in pupal chambers was thus indicated. For those bolts kept at 25℃ from 22 December, emergence rates were 100% for all photoperiods since diapause termination was well advanced due to exposure to both short day length and low temperature during the extra month. As wiltet pines in the field were assessed in this study, the propotion of empty pupal chambers in which larvae were parasitised or predated on was 78.9%, these chambers being occupied by Sclerodermus nipponicus (Bethylidae), cocoons of solitary parasitic wasps and larvae of the predatory beetle Trogossita japonica (Trogossitidae). To clarify responsibility for photoperiod more definitely, more precise experiments in the laboratory where parasitoids and predators are removed are considered necessary.

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In order to understand the latent photoperiodic period of post-diapause development of larvae of the Japanese pine sawyer, mature larvae in their pupal chambers were collected from bolts which had been placed in outodoor or indoor cages on 21 Nov. 1997 and then kept in glass bottles at 25-C under defferent photoperiods, i.e., at LD10:14, LD13:11, LD14:10, LD15:9 and LD16:8. For larvae collected from outdoor cages, the proportion pupating within three months were 14.3, 58.3, 65.4, 91.7 and 89.7%, respectively, and the latent period was thought to be around LD13:11 but it had a wide range. For larvae collected from indoor cages, the proportion pupating were 11.8, 12.0, 47.6, 76.2 and 82.6%, respectively, and the latent period was longer by one hour. Since higher temperatures and a longer light phase in the indoor cages before larval collection may have caused a lower degree of diapause termination, the propotion of larvae pupating was lower for larvae collected from indoor cages. Duration from the start of warming to pupation tended to be shorter as the light phase became longer.

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Predation of Trogossita japonica Reitter (Coleoptera: Trogossitidae) on the Japanese pine sawyer, Monochamus alternatus Hope (Coleoptera: Cerambycidae), the vector of pine wilt disease, was investigated by release of adults of both species into cages containing pine bolts. In an experiment held in 1996, both species were released simultaneously for two weeks in July. After the release period, most cerambycid beetles released with the predators were still alive and any dead beetles had no external wounds. Thus, it was clear that the predator was not able to predate on the adult of the cerambycid beetle in the field, and the predators were thought to have starved during the release period and so laid few eggs. In a similar experiment held in 1997, final instar larvae of M. alternatus were pinned on bolts as diet for the predators. Ovarial development showed that the female predators laid eggs. Bolts were then investigated further by cutting them open, and the number of cerambycid beetles in bolts did not differ from that of the control in which predators were not released. These results show that there was no observed effect of predation of larval offspring of released predators on larval offspring of released cerambycid beetles. Three larvae of the predator, however, were collected from outdoor cages where all bolts were heavily attacked by bark beetles but only one from indoor cages where only M. alternatus was present and where no bark beetles had attacked bolts. These results indicate that bolts containing various other invertebates may support the development of the predator and increase its predatory effect.

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The following two experiments were conducted to investigate the parasitism of Scleroderma nipponica on Monochamus alternatus. In the experiment with using an entomogenous fungus, Beauveria bassiana, the adults of the parasitoid were coated with conidia of the fungus and released under three different conditions; into vials containing a larvae of the beetle, into a field cages containing pine bolts bored by the beetles, and onto the dead pine trees standing in the field. The mortalities of the beetle's larvae were 87% in the vials, 89% in the bolts in the field cages, and 13% in the standing dead trees. In the experiment of mass release of the parasitoid, 800 adults per 1m^2 surface area of the dead pine trees standing in the field were released. The propotion of the empty pupal chambers of the beetle was 50%. This value was remarkably higher than that in parasitoid not-released trees (9%).

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Perennial canker due to Guignardia cryptomeriae, the casual fungus of Guignardia dieback, was first found on the stem of Cryptomeria japonica in Shimane Prefecture. The disease occurred in a 17-year-old Cryptomeria planted stand in Hasumi-mura. Frequency of infected trees was about 25% of all the trees examined at each middle and lower part of the slope and 3% at upper part. The canker lesions mainly expanded vertically in oblong shape around pruning scars. On the lesions, diameter growth was stopped because cambium was necrosed, and callus developed around them. The causal fungus, G. cryptomeriae, was isolated from stained xylem of the lesions. The sunken lesions were observed on the stem from the base to 4m above the ground and the xylem was stained to 6m. Diarrieter growth of the infected trees was extremely reduced in 1994 and stopped in 1995 on the lesions. Symptom of the disease, accordingly, was considered to develop between fall 1994 and 1995. The disease heavily occurred on trees on a steep slope in 35- and on gravel-mixed soil. Furthermore, drought was recorded in July and August in 1994. These ecological factors that caused water stress in Cryptomeria trees were supposed to predispose the trees to the disease.

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In order to clarify the number and behavior of Sika deer (Cervus nippon), light census were conducted in the Misen Mountains, the Shimane Peninsula, from 1994 to 1998. The census were done examined on three routes in summer and in fall every year. The Sika deer were observed 1.1-2.3 per 1 km of the routes. The density of population was higher in Izumo and Taisya-Inome than in Hirata. The number of bucks per 100 females was larger in fall than in summer. The number of calves was small, 20-28 per 100 femals. The buck groups decreased in fall and harem were observed only in this season. The density was high at young coniferous planted stands , slopes of roadside, and grasses, where Sika deer were considered to gather to feed grass.

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Soil carbon storage was investigated at two artificial hinoki (Chamaecyparis obtusa) stands of 78 years old, to study the effect of thinning on it. One stand (thinning plot) has been thinned 7 times, another stand (no thinning plot) has never been thinned. Surface Soil (A horizon+AB horizon) carbon storage of each plot was 39.5 t/ha, 68.5 t/ha, respectively. And soil carbon storage (1m in depth: A+AB+B+BC horizon) of each plot was 98.8 t/ha, 159.3 t/ha, respectively. These results were derived from difference of surface soil thickness of each plot; thinning plot had thick surface soil compared to no thinning plot. It could be thought that the understory vegetation that was preserved by thinning protected surface soil from erosion and provided soil organic matter, with that result surface soil of thinning plot was developed and conserved well compared to no thinning plot.

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In order to confirmthe causal fungus of the resinous stem canker of Chamaecyparis obtusa, inoculation experiments with some fungi isolated from the lesions, Cistella japonica, Cryptosporiopsis abietina, Amylostereum laevigatum, and non-identified fungi, were conducted onto the tree. Although resinous exudation was observed around the inoculated points inoculated with all of the fungi and even non-inoculated control one and two years after inoculation, fresh resin continously exuded for seven years from the lesion cause by inoculation with C. japonica. Seven years after inoculation, resin cysts were observed in inner barks of the lesions and the cambial texture were necrosed around the inoculated points. These external and internal symptoms were similar to those observed on natural lesions of the resinous stem canker. C. japonica was reisolated from the inoculated lesion tissues and isolation frequency of the fungus was higher in lesions where fresh resin continously excuded. No symptoms of the resinous stem canker, however, were induced by inoculations with the other fungi. As the results of inoculations, C. japonica was considered to be causal fungus of the disease.

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