Recently, the suburban bamboo forests have been expanding their distribution and invading the surrounding forests. This situation has been brought about by the abandonment of the management because of the difficult market situation caused by the mass import from China. To clarify the present situation of the production, management, market, and the grower's view, and also to know the problems to be solved, a questionnaire survey was carried out in Ooharano and Yamashiro areas of the famous bamboo shoot producing districts, in the suburbs of Kyoto City. (Execution in September, 2000, distribution: 235 people in Ooharano area, 252 people in Yamashiro area, and 487 total people, response rate: 52%) Results showed that although these two areas situated in similar bamboo shoot producing district in the suburbs of Kyoto City, there were differences in some features; a degree of intensiveness of management, sales method etc. These differences were thought to be related to soil conditions, the distribution patterns of bamboo forests, distances to the market, historical details etc. "Depression of the bamboo shoot price", "Heavy labor of the bamboo shoot production", and "Aging of the growers and insufficiency in their successors* were pointed out as the problems of the bamboo shoot production to be solved.

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The wood distribution has the principal function which links the wood producer with the wood consumer, and plays an important function economically and socially. The purpose of this study is to realize the stable local wood supply system in the Tottori Prefecture. In this study, what kind of differences come out for the formation of the log price in different tree species, basin and type independence of the log production were compared. By this investigation, the role which the each distribution stage should fulfil and future correspondence had to be reexamined. In addition, it is necessary to establish local wood supply system which includes the whole basin by attempting quantitative security, quality and standard unification, development of the discrimination goods, establishment of the stable supply system of the wood product. If this condition is realized, it will be possible to attempt mass production of logs and drastic cost reduction.

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The purpose of this study is to explore the present state and problems of farm life at Labagoumen Town of Kaijiu District of Beijing City, Northern China. The typical phenomena are not under population problems but superfluous population problem in China. Although the goods economy is developing in recent times, the population decrease continues and the tendency of depopulation and aging is also emerging in a part of farm and mountain village region. In this region, the farming business is becoming gradually serious as the population decreases. The people who engage in agriculture and forestry by remaining in the house are mostly women and aged people. In this study, the actual conditions and problems of the lifestyle of the farmer that formed the special communities under such situations were clarified. This study gives a demonstrative evidence of the suggestion which is useful for the modification of the farm and mountain village regional policy in China.

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Roughness of the road surface was evaluated by means of driver's systolic blood pressure change and its allowable limit was obtained. The systolic blood pressure increased rapidly more than 40mmHg as driving on the road where the surface roughness of ±7.5cm in height ×60〜90cm in length covers approximately 60% of the entire road length. This value of surface roughness should be considered as the criterion of allowable limit in repairing and maintaining forest road surfaces from the view point of the driver's psychological and physiological responses.

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We examined the effects of the dwarf bamboo sasa (Sasa nipponica) on the water potential of surface soil. We used 4 types of experimental plots in a forest at Ohdaigahara, in southern Honshu: with deer (Cervus nippon centralis) and either with or without sasa; and without deer and with or without sasa. The sasa biomass was highest in the plots without deer and with sasa. Although sasa grew back after sasa was cleared in spring, sasa biomass was lowest in the plots with deer and without sasa. At a depth of 6 cm, the matric potential was as follows: without deer and with sasa < with deer without sasa < with deer and sasa = without deer and sasa. In the plot without deer and with sasa, the matric potential increased slowly during periods of rain owing to rainfall interception by the large biomass of sasa that had built up as a result of deer exclusion. The soil was driest in this plot because of transpiration by the sasa. The next driest plot was that containing deer but no sasa; in this plot the minimum biomass of sasa led to an increase in evaporation from the surface. The matric potential was highest in the other 2 plots, which had intermediate sasa biomass. This finding suggests that a moderate biomass of sasa is needed to keep the surface soil moist.

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A tortuosity parameter of 0.5 suggested by Mualem (1976) is generally used to predict unsaturated hydraulic conductivity. However, the validity of using a parameter of 0.5 for forest soils needed to be confirmed. We evaluated the tortuosity parameter for forest soils under different site conditions. Undisturbed soil samples were taken from the forest soils which derived from the granite group and Mesozoic-Paleozoic and Quaternary sedimentary rocks. Retention parameters were first fitted, then the tortuosity parameter was optimized using the lognormal distribution conductivity model (the M-LN model) combined with Mualem's (1976) model. Most optimized tortuosity parameter values were less than 0.5; they varied from - 7 to 10 with a high frequency in the range of about - 1 to 0. This means that, for most forest soils, the predicted hydraulic conductivity tends to be underestimated when the most common value (0.5) of the tortuosity parameter is used. Modifying this to -0.72, as presented in this study, corrected the underestimation tendency and reduced prediction errors. When the unsaturated hydraulic conductivity for forest soils is predicted from water retention and the M-LN model, the tortuosity parameter should thus be modified to an appropriate value for more accurate prediction.

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To evaluate climate conditions and nitrogen deposition on wood decay, weight loss and nitrogen concentrations of Sugi (Cryptomeria japonica) and Hinoki (Chamaecyparis obtusa) were measured after 0.5 and 1 year at nine forest ecosystems in six regions of Japan. Nitrogen deposition by throughfall increased weight loss and nitrogen concentrations of wood after half a year, but the effect was reduced after 1 year. In contrast, the effect of mean annual temperature increased from 0.5 to 1 year. The effect of nitrogen deposition on decomposition was larger for C. japonica than for C. obtusa. This may be due to the differences in the substrate quality of woods and decomposing organisms.

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Ikenotani watershed of Kyoto University Forest in Ashiu is a young natural Sugi (Cryptomeria japonica) mixed stand. Various improvement cutting were performed in this area about 16 years ago. Considering the stand structure, we evaluated the effect to stand dynamics by different improvement cutting. The upper and middle layer cutting promoted the growth of valuable trees in canopy and including broad-leaved trees, consequently. On the other hand, lower layer cutting promoted the recruitment of saplings of Sugi. The significance of new improvement cutting methods corresponding to slope is emphasized.

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[in Japanese]

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We investigated birds eating dry fruits of a kind of wax trees Rhus sylvestris on a warm-temperate forest plantation in order to know the seed dispersal mechanisms of R. sylvestris. Five species of birds, those were the Pale thrush Turdus pallidus, the Dusky thrush T. naumanni, the Brown-eared bulbul Hypsipetes amaurotis, the Daurian redstart Phoenicurus auroreus and the Bull-headed shrike Lanius bucephalus, were seed dispersers of R. sylvestris among 8 species eating fruit of R. sylvestris observed. Birds ate fruits especially on the end of February. T. pallidus and T. naumanni spent much more time on the branches with fruits of JR. sylvestris and they ate much fruits, therefore those 2 species were main seed dispersers of R. sylvestris. Birds with wider gapes ate fruits more efficiently, and those with narrower gapes than fruits ate fruits by destroying or pecking. The seed dispersal distance by T. pallidus was considered less than 100m which was the width of their wintering territories. On the other hand, that by T. naumanni was supposed to be longer, because they do not have wintering territories.

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A filamentous fungus whose taxonomical name is not yet known has been suspected as the causal fungus of mass mortality of Quercus trees, because it is specifically found in the dead trees. This fungus is referred to as QM fungus in this paper. In order to utilize the dead trees, cultural features of Lentinula edodes (shii-take mushroom) and QM fungus were examined and L. edodes was cultivated using dead logs and their wood meal. Mycelia of L. edodes managed to grow even on the medium contained in the test tube in which QM fungus was vigorously growing. In a mycelial bed culture test, mycelia of L. edodes also grew well on the mycelial bed prepared with wood meal obtained from dead trees. Harvested fruit bodies showed no difference in number and weight between cultures made from dead trees and healthy trees. In a bed log culture test, mycelia of L. edodes spread in dead logs much more broadly than in healthy logs, even though QM fungus had infested dead logs at the time of inoculation. These results indicate that Quercus trees killed en masse can be used for both mycelial bed culture and bed log culture of L. edodes satisfactorily.

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Difference in flight time between male and female Platypus quercivorus that flew to a host tree was investigated in a forest of Quercus serrata and Q. crlspula damaged by the beetle. On cloudy mornings followed by sunshine, the female flight response peaked earlier than that of males. On clear mornings male and female flight reached a peak simultaneously, but females began and terminated flight earlier than males. We discussed that this difference is caused by a differential cost incurred by males and females before mating. Since cost for males may be to bore the entrance gallery, males fly in fine weather that make them actively after landing on the host. Since cost for females may be competition for a mate, females fly earlier irrespective weather in order to avert the competition.

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Eight species of Pestalotiopsis were collected from leaves of 13 broadleaved tree species in Shimane Prefecture, Japan. They are P. acaciae from Aucuba japonica, P. adusta from Pasania edulis, Eriobotrya japonica, Rhaphiolepis indica var. integrerrima, Rhododendron Metternichii var. hondoense, and Osmanthus fragrans, P. disseminata from Acer Buergerianum, P. distincta from Castanopsis cuspudata var. Sieboldii, P. glandicola from Quercus acuta, P. guepini from Camellia japonica and C. Sasanqua, P. malicola from Prunus tomentosa, and Pestalotiopsis sp. from Q. glauca. These hosts are novel for each fungus except for P. guepini. Grayish brown to whitish gray spots appeared on the infected leaves, with concentric rings in some cases. A dark brown band commonly bordered the lesions, separating them from healthy tissues. Acervuli of the fungus were produced on the adaxial or amphigenous leaf surface as black pustules, and became erumpent breaking through the epidermis. The lesions developed from the leaf margin or regions of injury by insects, suggesting that wounding was a prerequisite for the infection.

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Forest damage occurs in the common cormorant's (Phalacrocorax carbo) colony or roost. The relationship between colonization of the common cormorant and forest decline was studied at the Isaki Peninsula which faces Lake Biwa, Shiga Prefecture. The forest was classified into 5 types according to both number of nests and the extent of forests. Individual trees were classified into 5 -damage degree from healthy to death. Five plots, 0.25ha each, were established for examining the influence of the nesting on individual trees. Tree species, DBH, the number of nests and the extent of the trees healthy were checked up in each plot. An 2,000 m belt transect was set to estimate the situation of forest decline, the total number of nests and vegetation cover in the whole study area. At the most part, nests were found on declining trees, and no nest was observed at dead trees in all plots. The analysis of increment core sampled from about 40 trees showed that the dam- age degree of tree can be an index for the tree's physiological decline. The number of common cormorant's nests have been increasing and forest decline have been proceeing in the peninsula since 1996.

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To control the Japanese pine sawyer using woodpeckers, we researched the habitat features of their nests, and tested the availabilities of short logs and bottomless roost boxes (Nakamura et al. 1995) for their breeding or roosting. The researches on nesting habitat showed that the Japanese green woodpecker (Picus awokera) bored the nest holes in the trunk of live deciduous broad-leaved trees in many cases, while the great spotted woodpecker (Dendrocopos major), the white-backed woodpecker (D. leucotos) and the Japanese pygmy woodpecker (D. kizuki) used dead trees or dead boughs also. The Japanese green woodpecker and the Japanese pygmy woodpecker bored entrance holes of their nests in short logs, showing that they selected the short logs for nesting. However, they did not complete the nest holes. Bottomless roost boxes were rarely used by woodpeckers. This suggest that it is difficult to attract woodpeckers using this type birdboxes.

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The stick type greening devices originally developed by Okayama Prefecture Forest Experiment Station were applied on a road side slope from February to June 1997. Six devices (A, B, C, D, E and F) contained different combinations of acorns of oaks that were Quercus variabilis, Quercus serrata, Quercus glauca, Quercus mysinaefolia, Quercus phylliraeoides and Castanopsis cuspidata. The culture medium of A, B and F devices was vermiculite only and that of the C, D and E devices was a mixture of vermiculite, granite soil and bark composit. Results were as follows. (1) The germination rates of Quercus variabilis until the middle of April, Quercus glauca until the middle of June, were more than 60% when preserving seeds at below 5℃. (2) The height growth of these oaks was worse than soil improve trees such as Myrica rubra and Alunus sieboldina in all devices. (3) Mortalities of all oakswere less than 20% after three growing periods. (4) The vegetation cover ratio was more than 60% in June 1998 when the range of device interval was 30-40cm. It is suggested that though the height growth of oakswas bad, the stick type greening device waseffective for an initial greening if soilimproving trees were mixtured in the device even on the slope which slant was 40-48° and the soil hardness by yamanaka mesuring instrument was 16-20mm.

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