We examined pre- and post-dispersal seed predation in Prunus verecunda in a deciduous broad-leaved forest, northern Japan. Few seeds died before dispersal, but most seeds were preyed upon by small rodents on the forest floor after dispersal. Although the seeds on the forest floor died of rot at a high rate when vertebrates were excluded, most seeds survived when vertebrates and invertebrates were excluded. Many burrower bugs (Macroscytus japonensis) were observed around seeds in experiment plots. As soon as we fed the burrower bugs on P. verecunda seeds in the laboratory, they stuck their proboscises into the side of seeds and sucked the seeds. We inoculated intact seeds and the seeds sucked by the bugs with fungi isolated from rotten seeds. Most sucked seeds then rotted, although few intact seeds rotted. Therefore, the sucking by the burrower bugs probably induced seed-rot by fungi in P. verecunda seeds even if the seeds escaped predation by small rodents on the forest floor after dispersal.

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Model parameterization was performed for estimation of the fuel moisture in adjacent plots with different tree species aiming at the mapping of forest fire hazard. One plot was covered with only deciduous species and the other with deciduous and evergreen trees. This model has four constant parameters. Three of them are for the relationship between evaporation and solar radiation. Another parameter is the maximum water content ratio of the litter. All of these parameters depend on the intrinsic drying properties of the litter. The water content ratio of the litter and solar radiation on the forest floor were measured in each plot for one year. Parameters were fixed with the measured data. Though the parameter values were very different between the two plots, estimated moisture ratios were not so different. It was concluded that litter moisture depends on the microclimate, such as solar radiation, rather than on the intrinsic drying properties of the litter and litter layer.

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Two C. japonica trees exhibiting male sterility were found in Niigata Prefecture, Japan. These trees exhibited not only male sterility but also female sterility, because their seeds did not germinate. Both trees were pollinated normally in the pollen dispersal season in April. There were initially no differences in ovules between sterile and normal trees. However, differences appeared in the ovules from May to June. The female gametophytes underwent repeated nuclear fission, and a free nucleus was formed in the seeds of normal trees. However, a free nucleus was not formed in the female gametophyte, and there was adhesion during the free nucleus stage in the two sterile trees. Archegonia did not develop, and the gametophytes degenerated. Moreover, all seeds from the two sterile trees were unviable. The degeneration in the female gametophytes of the two sterile trees was similar. As no free nucleus formed in the two sterile trees, the cause of female sterility is believed to be abnormalities in meiosis in the megaspore mother cell, resulting in failure to form a normal female gametophyte.

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An educational project was conducted both to understand problems in carrying out a forest educational program in primary and secondary schools and to find their solutions. Our program aimed to let students understand multiple functions and utilities of forests. A training workshop for teachers at primary and secondary schools was held, showing them a practical model of the forest education program. Furthermore, questionnaire surveys for the teachers were carried out both before and after the workshop. Interests of participants in the forest functions were high both before and after the workshop. A statistical analysis indicated that the workshop provided teacher with progress in knowledge, interpretation, techniques, and motivation for future sessions of the forest educational program. However, possibilities of combining the program with their curriculums remained relatively low. In free-style answer sheets of the questionnaires, most teachers complained about lack of instructors, difficulties in finding sites for conducting forest educational programs, insufficient budget, and time constraints for the sessions. To mitigate these issues, specialists such as researchers in universities should provide teachers in schools with materials and instruments for education programs, so that the teachers can spend more time on teaching as instructors.

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Shakain is one of the cutting cultivars of Cryptomeria japonica in Kumamoto Prefecture. We established a clone classification system using the CAPS (Cleaved Amplified Polymorphic Sequences) markers for clarifying the clone constitution of this cultivar and utilizing it exactly as a seed resource of cutting seedlings. As a result of screening 33 markers previously reported, six markers showing the stable PCR amplification, easy to genotype specification and co-dominance type were chosen. A classification result of 16 Shakain individuals by these CAPS markers accorded with a result from 6 microsatellite markers. The possibility of clone classification using this marker system was evaluated and we applied these markers for further analysis. Two hundred and twenty Shakain individuals which had been planted around Kumamoto Prefecture were classified into 27 DNA types, and two major DNA types of these accounted for 78.6%. According to the ratio of DNA types in each afforestation area, it was likely that a cultivar Shakain was derived from the selection in the general seedling afforestation area.

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We examined the seed dispersal and germination of Styrax japonica to determine the effects of the fruit pulp involving saponin and its removal by the varied tit (Parus varius) on the seed germination in a broad-leaved forest of northern Japan. All mature fruits disappeared from the trees by September. Only varied tits visited the trees, and 80% of their visits were spent on transporting mature fruits in four days. As 83.0 to 87.2% of the fruit that disappeared from trees was taken by varied tits, most of the fruit was probably transported from the trees by these birds. The remaining fruits naturally fell to the ground, and their pulp remained until mid November. In a germination experiment in the field, the seeds deliberately extracted from the fruit pulp had a significantly higher rate of germination (mean 36%) than the intact fruits (mean 4%). Since the level of saponin in the fruit pulp decreased after the fruit fell to the ground, it is unlikely that saponin in the fruit pulp prevents seed germination. The caching behavior of varied tits probably contributes not only to seed dispersal but also to seed germination because it accompanies the extraction of fruit pulp, which prevents seed germination.

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This study aims to develop a methodology to account for and identify forests under Article 3.4 of the Kyoto Protocol (forests under Art. 3.4), and then to calculate forest area under Art. 3.4. Forests under Art. 3.4 can be defined as “forests receiving silvicultural practices such as planting, weeding, pruning, pre-commercial thinning, and commercial thinning from 1990.” Two approaches can be considered to calculate forest area under Art. 3.4 by using 1) the forest register and 2) practice records of the private plantations in Gifu Prefecture, Japan. As a result, we found that practice records were more suitable than the forest register for calculating the forest area under Art. 3.4. However, it might be possible to use both types of data, depending on their purpose and/or availability, since there were no significant differences between the two data sets. In addition, the two approaches together suggested that the forest area under Art. 3.4 covered approximately half of the plantations in the period 1990 to 2000.

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We produced seeds of Cryptomeria japonica trees in a glasshouse miniature seed orchard to prevent pollen contamination. In the glasshouse, male flowers shed pollen from February 4 to March 27, 2002, whereas female flowers were open from February 5 to March 22, 2002. Outdoors, pollen of Cryptomeria japonica was dispersed from February 21 to April 6, 2002. Flowering in the glasshouse was approximately three weeks earlier. Peak flowering of male flowers was from February 17 to March 13 and that of female flowers was from February 15 to March 3, 2002 in the glasshouse. The peaks of flowering of male flowers and female flowers overlapped. The germination frequency of seeds produced in the glasshouse was almost the same as that of seeds produced in outdoor seed orchards. We conclude that a glasshouse miniature seed orchard is effective in preventing pollen contamination.

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Larvae of the swift moth Endoclita excrescens (Butler) were reared on a commercial silkworm diet for 220 days under a long (LDT ; 16 : 8 h light/dark) or short (SDT ; 10 : 14 h light/dark) photoperiod at 25°C. Larvae pupated at a higher rate under LDT (37.6%) than under SDT (13.6%). Both males and females pupated under LDT, while only male pupae were observed under SDT. The emergence rate was higher under LDT (25.6%) than under SDT (12.8%). The mean duration of the larval period of males and females under LDT and males under SDT was 158.6, 159.7, and 151.6 days, respectively. The mean duration of the pupal stage of males and females under LDT and males under SDT was 23.9, 22.6, and 22.5 days, respectively. These results indicate that pupating is related to photoperiod and that E. excrescens larvae can be reared on a silkworm diet at 25°C under a photoperiod of 16 : 8 h of light/dark to obtain a high pupating rate.

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Fifteen resistant individuals were selected from 38 sexually reproduced, open-pollinated seedlings from a pine wilt disease-resistant clone (Sendai (t)-290) of Japanese black pine (Pinus thunbergii). They were propagated as rooted-cuttings, and the resistance of their ramets to the disease was evaluated by inoculating them with pinewood nematodes (Bursaphelenchus xylophilus), Shimabara population, which is widely used for this purpose, in three successive years. The proportion of ramets that were not damaged following this treatment ranged from 61 to 71% in the three years, and there was little between-year variation in the resistance levels of the cutting-propagated plantlets. Moreover, using two nematode isolates (Ka-4 and Karatsu 3) which are more virulent than the Shimabara population, nine resistant individuals were selected out of 18 open-pollinated seedlings from 12 resistant clones. These individuals were propagated by cutting, and their ramets were inoculated with a more virulent isolate, Karatsu 3. The ramets showed extremely high degrees of resistance, and 97.7% of them were not damaged. These findings suggest that the cutting-propagation of ortets selected by using virulent isolates offers an effective method for the practical production of plantlets resistant against pine wilt disease.

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Eight hundred and thirty-five sugi (Cryptomerica japonica D. Don) plus-tree clones from the Kanto Breeding Region were genotyped using three highly polymorphic SSR markers. With a mean observed heterozygosity of 0.831 and discrimination power at a locus varying from 0.98 to 0.99, the SSR markers were more effective for discrimination than RAPD (Random Amplified Polymorphic DNA) markers. Although five other markers were added to discriminate the remaining 189 sugi plus-tree that indicated the same genotype using three markers, only 6 plus-tree clones possessed the original genotype. One of 8 SSR markers, Cjgssr149, seemed to be multi-locus, and the SSR motifs of two clones were sequenced to verified whether it was multi-locus or not. As a result, it revealed that a duplicated SSR region was amplified.

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