The effects of the thinning season (winter or summer) and the bucking method (non-bucked, bucked to 2 m, or bucked to 6 m) for sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa) on the moisture content of sapwood, the emergence of Urocerus japonicus adults, and their sex ratio were investigated. Control of the emergence of U. japonicus adults by the thinning season and the bucking method was examined. The difference in moisture content by the thinning season was not remarkable. However, the amount of emergence was smaller in winter than in summer, and this tendency was more significant in hinoki. On the other hand, the moisture content and the number of emerged adults were changed significantly with the bucking method. The range of moisture content in which many adults emerged was 80170% for sugi, and 50150% for hinoki. The range corresponded to the tree bucked to 6 m for sugi, and the tree bucked to 2 or 6 m for hinoki, respectively. It was suggested that the emergence of U. japonicus adults could be controlled by the thinning season. On the other hand, in the case of the trees felled in winter or summer, the bucking didn't control the emergence of adults. It was suggested that the emergence of adults is promoted rather than controlled by the length of bucking.

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The number of Platypus quercivorus landing, the number of entry holes bored by the beetle, and the ratio of the beetle's reproductive success were investigated on bait logs of Querucus crispula cut into various lengths. Water content of the logs was also measured. The ratio of galleries with eggs or larvae was low on both the short logs and the edge of each log, where the water content was low. The number of beetles landing on the short logs was small, and the number of entry holes was small on both the short logs and the edge of each log. The water content where the beetles failed to reproduce was less than 60%, and the oak pathogenic fungus, Raffaelea sp., which might be indispensable for the beetle's reproduction, was scarcely isolated from there. These results suggested that P. quercivorus landed on and bored into logs, avoiding those parts with low water content where the beetles failed to reproduce. Other ambrosia beetles also intensely attacked the logs, and the landing peaks of these beetles, except for Xylosandrus gerrnanus, were delayed from that of P. quercivorus. It was clarified that preventing the decline of water content, such as by making the length of bait logs greater than 1 m and avoiding direct sunlight, was important in pest control by using bait logs. In addition, it was suggested that the time immediately after the beginning of emergence of P. quercivorus was the best time for establishing bait logs.

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We investigated the dry weight of logging residues in thinned stands of Japanese cedar (Cryptomeria japonica) of various ages. The dry weight of the logging residue in each stand was estimated at 13.138.4t•ha^-1 from plot inventories. Stepwise multiple regression analysis showed that stand volume, relative density, and thinning ratio significantly affected the ratio of wasted log volume to thinned volume. Furthermore, stand age and time after thinning significantly affected the dry weight of wasted branches and leaves. Analysis of covariance showed that the dry weight of the wasted leaves and secondary branches decreased with time after thinning. In conclusion, the usable dry weight of logging residue can be estimated from stand development stage, stand density management, and the time when logging residues were harvested.

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Mountain villages are sketched in "Miyako-Meisho-Zue" and "Shui-Miyako-Meisho-Zue, " lists of places of interest in Kyoto in the Edo period, although their titles contain the word "miyako" (capital Kyoto). This paper concludes that the view of capital and sights of interest in the Edo period included mountain villages and that mountain villages around Kyoto whose culture was unique and different from that of capital were already involved in sight points destinations. Through analysis of pictures, "waka" (classical Japanese poems), and writings which were illustrated with people in the villages, it was found that regional characteristics of Daihizan, Kurama, Yase, and Ohara were emphasized by describing two types of places of interest. One is characterized as a place of production : scenes of producing and transporting forest production carried on by active and skillful villagers. The other is characterized by appreciation : scenes of natural environment and off-the-beaten-track seclusion. This paper suggests that these characterstics of sights of interest of mountain villages around Kyoto were propagated as a view of mountain villages in the Edo period.

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The height growth of 58 thinned trees (from stands 101 to 228 years old) was measured for the last 2 to 4 years before thinning in eight manmade sugi (Cryptomeria japonica) stands in Kawakami Village, Nara Prefecture. In suitable sites for growth of sugi, it was confirmed that the trees, which were all around 110 cm in DBH and 50 m in height, can grow upward every year, even in the 228-year-old stand. The annual height growth of the thinned trees ranged from 4 cm to 19 cm per year. The means of the minimum height growth showed small differences among different-aged stands, while the means of the maximum height growth showed large differences and tended to decrease with increasing in stand age. Thus, one difficulty in utilizing the stand density control diagram became solved, namely that the height increased every year even in old manmade sugi stands.

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In order to raise a healthy pond cypress forest under wetland conditions, a study on tree growth and nutrient properties in different water table sites was performed in a 17-year-old pond cypress wetland plantation which was located in the Lixiahe region of the Jiangsu province in China. Based on the investigation of the water table, the study sites were divided into three groups : high, middle, and low. The sites were flooded for about 6, 1, and 0 months per year, respectively. The depth of the mean water tables for one year was -2±12, -15±13, and -37±12 cm, respectively. The stem volume of the pond cypress located in the high, middle and low water tables was 45±8, 142±16, and 187±24m³ha^-1, respectively, and the above-ground biomass was 33, 73, and 114 Mgha-1, respectively. The ratios of the above-ground and below-ground biomass decreased from 2.7 to 1.5 with the increase in the water table. The growth of the pond cypress was seriously inhibited when the depth of the mean water table was higher than -10cm, or the flooding period was longer than 1.5 months in one year. Compared to the middle and low water table sites, the soil pH in the high water table site increased by 0.5 to 1.1 units, but the total C and the total N contents decreased by 30%. The concentrations of exchangeable K, Ca, Mg, Na and total Fe in the soil were the lowest in the high water table site and the highest in the low water table site. The concentrations of NO₃-N in the soil were not detected when the sites were flooded. Nutrient concentrations in leaves were not significantly influenced by the differences in the water table conditions except for an increase of Mn in the high water table. In the case of roots, N and Ca concentrations were higher, and Fe, Mn and Na concentrations were lower in the low water table site than in the other water table sites.

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In this study, information on forests and forestry, which was actually publicized through WWW, was classified and counted according to home page administrators and information content. At the same time, Internet users' needs for information on forests and forestry were surveyed using a WWW-based questionnaire. As a result, Internet users were shown to be interested in daily-use products such as mineral water, nature/recreation such as forest therapy, and environmental problems such as acid rain. Conversely, they were not interested in forestry-related topics such as forestry machines. Internet users' interests were classified into environmental problems, forestry, forests, qualification/volunteer activities, areas famous for forests and forestry, recreation, food obtained in forests, outdoor activities and industrial products by using the cluster analysis. Among these, many of the respondents were interested in outdoor activities regardless of their age. It was found that there was a gap between information that was publicized through WWW and Internet users' needs for information except "recreation. "

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The clonal structure of Measa, a kind of cutting cultivar of Cryptomeria japonica in the middle and southern part of Kyushu, was examined with RAPD markers. Forty-two elite trees provisionally classified as Measa or Ao-sugi (another name of Measa) in the table of cultivar character were investigated. These trees showed 22 DNA types. Of the 43 old Measa trees planted in shrines and temples in the middle and southern part of Kyushu, 41 trees showed the same DNA type. These trees were distributed in 4 prefectures. It was shown that one clone was dominant in Measa based on the analysis of clone constitution of this cultivar.

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In March 1999, we measured the number of bacteria in the soil where Pinus thunbergii grew on the scoriae accumulated at volcano eruptions at Miyake-Jima, Izu Islands, Japan. The number of bacteria was high on the surface of ectomycorrhizae of P. thunbergii and in mycosphere soil of ectomycorrhizal fungi associated with this tree. Capacity of Alnus sieboldiana nodulation and of ectomycorrhizal formation of A. sieboldiana- and P. thunbergii seedlings were also compared in the soils where these plants grew in this site. Nodulation capacity of A. sieboldiana was high in rhizosphere of A. sieboldiana and low in the mycosphere of ectomycorrhizal fungi of pine. No nodulation was observed in non-mycosphere soil of this site. Abundant mycorrhizae were formed on alder seedlings cultivated in rhizosphere of the alder and on pine seedlings cultivated in mycosphere soil of ectomycorrhizal fungi of the pine. No ectomycorrhizae were formed in pine and alder seedlings cultivated in non-mycosphere soil.

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It is often said that the shallow rooted characteristic of coniferous tree species such as hinoki cypress and Japanese cedar leads to the collapse of relatively-young artificial forests when they meet with extraordinarily heavy rain. To examine this claim, we compared the vertical root distribution pattern between hinoki cypress (Chamaecyparis obtusa) and an oak (Quercus crispula). In a 48-year-old hinoki plantation, a hinoki individual (DBH : 14.2 cm, H : 11.9 m) and oak individual (DBH : 12.8 cm, H : 8.3 m) invading there were selected. Under each sample tree, a trench of 20 cm wide, 100 cm long, and 60 cm deep was dug, sited for the three directions from stem base, i. e. , up-slope, down-slope, and side-ward. The trench was further sub-divided into soil blocks of 10 cm deep and 20 cm wide. The horizontal distribution pattern of root weight on slope was different between the two sample trees. The oak sample tree developed much root in the up-slope direction but the hinoki in the down-slope direction. The vertical distribution of root weight density decreased exponentially with soil depth. The decreasing rate of root weight density was not different statistically between the two sample trees. The individual root weight was calculated by integration of the exponential equations for the arbitrary soil depth. The individual root weight from soil surface to 30 cm depth formed 89 and 94% of total root weight for the oak and hinoki, respectively. The two sample trees showed similarly the shallow rooted behaviour.

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