Nonwoven fabric sheets on which Beauveria brongniartii was cultured have previously been used for killing two longicorn beetles, Psacothea hilaris and Anoplophora malasiaca in plantations in Japan. This study shows that the same method can be used to kill another longicorn beetle, Apriona japonica, which damages various broadleaf trees. A. japonica was found to be damaging a mixed forest of Robinia pseudoacacia and Celtis sinensis at Uchinada, Ishikawa Prefecture. The adults were thought to use R. pseudoacacia trees for ovipositing and C. sinensis trees for feeding. Some of the fungus-containing sheets were hung on the C. sinensis trees to infect the adults feeding on the tree. The total mortality of the adults captured on the experimental site was 55.0% for 41 days (n=56) and the maximum was 80.0% on 12 days after the application. Marked adults were collected for 41 days after the application on the experimental site and the collecting rate was 6.6% (n=412). Because 12 of these adults were dead from contagion when collected, the mortality was 44.4%. These results suggest that application of funguscontaining sheets on trees where the adults congregated for feeding can kill A. japonica adults effectively.

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Large-scale and rapid conversion of semi-natural forests to conifer plantations should have a great impact on regional biodiversity. On the other hand, it is expected that multiple-layered forestry management will lead to the conservation of regional biodiversity. We investigated the difference in the assemblage of longicorn beetles between Ehime Kumakôgen-cho or a large forestry area and the neighboring old-growth forest where original vegetation remains, as well as the associations of the assemblage of longicorn beetles with the forest types (single-layered conifer plantation, multiple-layered conifer plantation, and second-growth forest), forest age, plant species richness, and volume of fallen trees. In Kumakôgen-cho, the assemblages of longicorn beetles that were dependent on mature forests were on the decline. Correspondence analysis (CA) of the longicorn beetle assemblages showed that none of the forest types formed a cluster. A significant negative correlation was accepted between the site score for the first axis of CA, in which the old-growth forest showed the minimum value, and the number of plant species. Therefore, although multiple-layered forest management does not necessarily recover the assemblage of longicorn beetles, irrespective of the forest type, it is possible that suitable management of the undergrowth to increase the number of plant species plays a role in the preservation of the original assemblage of longicorn beetles.

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Regeneration of Fagus crenata was examined in the experimental forests managed by a shelterwood system at the Kurosawajiri Research Site, Iwate Prefecture. In a stand where clearing of the forest floor was carried out after shelterwood logging (6 residual trees per ha) in 1948, the secondary forest dominated by F. crenata had been formed. In a stand without clearing of the forest floor after shelterwood logging (13 residual trees per ha) in 1969, the resulting secondary forest was dominated by Prunus grayana and Magnolia hypoleuca, and regenerating F. crenata trees were not frequent. In a stand with clearing of the forest floor after shelterwood logging in 1969, many regenerating F. crenata trees were found, representing the L-shaped size structure, but their distribution was limited to under and around the residual conspecific canopy trees and they seldom occupied the upper layer. These results demonstrate that stands in which F. crenata seedlings had been established owing to clearing of the forest floor do not always turn into F. crenata-dominated stands. In addition to the timing between the practices and seed production fluctuation, differences in the abundance of F. crenata seedlings before cutting may be an important factor causing the difference in the regeneration success of F. crenata between the two stands in which the forest floor treatment was carried out.

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Early in the Meiji era, as the demand for Western manufactured paper increased and producers of traditional Japanese paper began to feel at a disadvantage, the Paper Department of the Printing Bureau of the Ministry of Finance and producers of Tosa paper in Kochi Prefecture developed new techniques of papermaking and made new kinds of paper. Histories of the Printing Bureau of the Ministry of Finance and Yoshii Genta's diary track the unique development of new types of light-weight paper made from mitsumata (Edgeworthia chrysantha Lindley). Records of domestic trade expositions show that the technique of making these kinds of paper tended to be introduced to regions where there had been a tradition of making mitsumata paper. The improvement and specialization of functional paper met diverse contemporary demands, and was perfectly placed to be exported to supply similar international demands. These new techniques contributed to the polarization of regions according to types of paper produced and profoundly affected local economies. They also helped to promote functional use of paper for specialized purposes besides writing and wrapping.

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Seasonal variation in the spectra of bamboo, broadleaved forests, and coniferous forests was examined using multi-temporal SPOT/HRV and LANDSAT/TM data and ground-based spectral measurements. The satellite- and ground-based data revealed some common characteristics. In the visible red region, bamboo forests had the highest digital number and reflectance factor from April to June. In the near-infrared region, bamboo and broadleaved forests exchanged ranks from spring to summer. In the short-wavelength infrared region, bamboo forests had higher digital number than broadleaved and coniferous forests throughout the year. The three forest types showed significant differences in the near-infrared region from May to July and in the short-wavelength infrared region during the almost entire year. It is suggested that “leaf exchange” greatly affects seasonal variations in the spectra of bamboo forests.

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We analyzed the species and densities of established tree with height≥1.3m in 59 conifer plantations and 41 reforestation-abandoned sites after clear cutting (i.e. clear-cut sites) on Kyushu Island. Natural or secondary broad-leaved forests (i.e. broad-leaved forests, n=17) were also investigated for the purpose of comparison. Based on these field data, we developed prediction models for tree establishment. Mean densities of trees established in both plantations and clear-cut sites were lower than in broad-leaved forests, especially for species dominating the canopy layer of natural forests, such as Fagaceae. The coefficients of determination of the prediction models were larger for a group of pioneer tree species than for all pooled species in both plantations and clear-cut sites. Major factors affecting tree establishment were different between the plantations (slope inclination) and the clear-cut sites (altitude and slope direction), although stand age (including years after clear-cutting) affected tree establishment most in both sites. Basic site information (e.g. altitude) and stand description data (e.g. stand age) were useful for the prediction. The accuracy of the prediction model was improved by grouping tree species with similar growth and/or regeneration characteristics.

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By analyzing the wind damage caused by the typhoon 200221 at shelterbelts of Tokachi in Hokkaido, it was found that tree species, orientation of shelterbelts, stand age, and species of windward sub-compartments (windward forest) were the major factors for the damage. Among the major species in the shelterbelts, oak (Quercus dentata Thunb.) showed the highest resistance to uprooting; it reduces the wind damage if established along windward sub-compartments. The NNE and NE extended shelterbelt is subject to damage as the wind blows in the SE direction perpendicular to it; therefore, plantations of oak trees along the shelterbelts should be given a high priority in order to reduce the wind damage. From the investigation of undamaged and damaged Japanese larch (Larix leptolepis Gordon) stands having similar stem volume, it was understood that the stand density was smaller and diameter was larger in the undamaged stand than that of the damaged stand. Furthermore, the records of forest management for Japanese larch stands, aged between 35 and 45 years, suggested that the thinning frequency is lower and stand density of the damaged stand is 1.8 times higher than that of undamaged forest. To enhance the resistance of Japanese larch stands to uprooting, it is necessary to reduce stand density to 400 trees/ha or less by thinning them two or three times before they reach the age of 35 to 45 years.

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Soil respiration rate was measured for 2.5 years along the slope at Kiryu Experimental Watershed in Shiga Prefecture, Japan. The soil respiration rate was lower at the bottom of slope with saturated conditions, than that at the upper part of slope with unsaturated condition. Seasonal fluctuations of the soil respiration rate were related to soil temperature and soil water content. Drought induced the decline of the soil respiration rate. The soil respiration rate exponentially increased with soil temperature and Q₁₀ ranged between 2.00 and 2.20. The second order polynomial model fitted best for the relationship with soil water content. Using these relationships, annual soil respiration was estimated to be 692±21, and 716±46g Cm^-2 yr^-1 for 2003 and 2004, respectively.

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A study was conducted to examine the effects of various soil moisture conditions on endangered species star magnolia (Magnolia tomentosa) seedlings in a greenhouse. Four treatments representing a range of soil moisture conditions, from continuous flooding with or without stream to moderate drought, were imposed separately. A well-watered with well-drained treatment served as the control. Leaf phenology and water potential of 2-year-old seedlings were evaluated. Decreased number of leaves of shoots clearly demonstrated the sensitivity of seedlings to low oxygen conditions derived from flooding as well as to soil water deficit. Predawn leaf water potential was declined by drought treatment. Leaf water potentials at turgor loss were declined by flooding and drought treatments. Leaf osmotic potential at full turgor declined only by flooding treatment. These results imply leaf osmotic adjustment against flooding and leaf elastic adjustment against drought stress in M. tomentosa. Little differences in leaf phenology and in water relation were found between stream and control treatment. These results indicate swamps with spring or stream are indispensable for conservation of M. tomentosa.

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In order to evaluate the role of frugivorous birds in the dispersal of broad-leaved tree seeds in a plantation of Japanese cedar, Cryptomeria japonica D. Don, we monitored seed rain with 120 seed traps distributed over the plantation and an evergreen broad-leaved forest close to the plantation at the Kagoshima University Forest from October 2002 to April 2004. The numbers of bird-dispersed seeds and their seed species deposited in the traps in the plantation were significantly larger than those derived from naturally fallen fruits. Seasonal and yearly variation of bird-dissemination was observed in the plantation; the frugivorous birds deposited more seeds in the autumn-winter season than in the spring-summer season, and in 2002 than in 2003. In the plantation, naturally fallen fruits were localized around the broadleaved forest, while the bird-dispersed seeds were widely dispersed randomly. We also conducted a bird census in the study area for 43 days from February to December 2003. We observed 14 frugivorous bird species in the study area, and among them, the Brown-eared Bulbul, Hypsipetes amaurotis, was observed most frequently. These results suggest that frugivorous birds, especially H. amaurotis plays an important role in seed dispersal in the conifer plantation.

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The purpose of this study was to clarify the effects of tree species on organic matter dynamics according to stand age in Kanto region of Japan. We investigated forest floor cover percentages, amounts of forest floor and litterfall, and soil carbon content for cedar and cypress forests. Study-plots in the forests planted with Japanese cedar and Japanese cypress were adjacent, on the same slope, with different stand ages (13, 21, 34, 48, 66, 93 years old). Comparisons of the results were made between the cedar forests and the cypress forests. The amount of annual litterfall in the cedar forests decreased with stand age, but in the cypress forests it was unchanged with stand age. The needle leaves in the soil were 1.5∼7.3Mg ha^-1 in the cypress forests. There were more needle leaves in the cypress forest soil than in the cedar forest soil. The quantity on the forest floor added to the needle leaves in the soil in the cedar forests was almost the same for each cedar forest stand age. The quantity on the forest floor added to the needle leaves in the soil in cypress and cedar forests increased in stands from 13 years old to 34 years old, and was unchanging for stands which were more than 34 years old. The residence times of litter C (standing stock of litter/annual litterfall) shortened with stand age in the cypress forests, and lengthened with stand age in the cedar forests. The soil carbon content did not change with stand age in the cedar and cypress forests. The organic matter decomposition rates on the forest floor in the cypress forests were more active than those of the cedar forests. However, the soil carbon contents in the cypress forests were almost the same as those of the cedar forests. This suggested that the carbon mineralization rates of the litter in the cypress forests had been more easily mineralized, relative to the cedar forests.

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Nitrate nitrogen (NO₃-N) concentrations of stream water have been observed in the headwater catchments within Gunma Prefecture located in northwest of Metropolitan area Japan. Large differences of NO₃-N concentrations were observed between the west side and the east side of Tone River which flows through Gunma Prefecture in north and south. There is positive correlation between rainfall events and increase of the NO₃-N concentrations of stream water in the east side. On the contrary, no correlation is found out in the west-side where the NO₃-N concentration is high. These phenomena suggest that the nitrogen saturation occurred in the west side of Tone River. The nitrogen saturation is supposed to be occurred by dry and wet atmospheric depositions that are transported by the wind from the Metropolitan area.

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Experiments were carried out to investigate the germination traits of Fraxinus lanuginosa fruits. The optimal temperature for germination was 20°C; although fruits at lower temperatures (10°C and 15°C) retained their viability, their germination was inhibited. While seeds extracted from fruits showed significantly higher germination percentages than intact fruits, partial scarification of the pericarp to enhance water permeability to the inner seed did not facilitate germination. This indicates that the dormancy of the fruit is mainly due to the physical inhibition of embryo growth by the pericarp. A pre-moist chilling treatment had a significant effect on breaking dormancy and enhancing the germination rate. However, since a substantial number of intact fruits was able to germinate without pre-treatment, we concluded that the dormancy of F. lanuginosa fruit is not very deep. These traits would be sufficient to prevent precocious germination of F. lanuginosa during the fruit-dispersal season in southeastern Hokkaido, Japan, which is characterized by a cool autumn followed by a severe winter.

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To examine methods of overstory cutting in two-storied stands of sugi (Cryptomeria japonica) and hiba (Thujopsis dolabrata), clearcutting and thinning (45% cutting by basal area) of the overstory (50 years) were conducted in two-storied stands with an understory height of 3.2m. Damage and growth of the understory were subsequently measured. No significant difference was found in the ratios of damaged understory trees for clearcut and thinned stands. Three years after overstory cutting, the growth in height and diameter at breast height of the understory was highest in the clearcut stand and lowest in the control stand. Rapid changes in the environmental condition of the forest floor by overstory clearcutting caused no damage, such as growth hindrance or drought damage, to understory trees. Therefore, the clearcutting method is recommended for two-storied sugi-hiba stands.

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We investigated paternal contribution in artificial crossed-populations made by mixed pollen from plus tree clones of Cryptomeria japonica D. Don in Niigata Prefecture. Using six polymorphic microsatellite markers, we identified male parent for each individual tree. We detected significant distortion from equal contribution of male clones in some populations by chi-square test. Therefore, we have to carefully design sugi control pollination with mixed pollens and their use for progeny test.

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