Artificial forests account for approximately 40％ of the forested area in Japan, and these forests are expected to serve not only as timber sources, but also as important habitats for wildlife. However, the diversity and ecology of species constituting this ecosystem is not well understood. In this study, we revealed the bird species that observed in Japanese cedar and cypress plantations and discussed the ecological characteristics of the species. Surveys were conducted at 57 study points located in 3 mountain areas in western Kanagawa Prefecture during the breeding season of birds from May to June from 2014 to 2018. We observed 45 species of birds within 8 orders and 26 families in the forests; the number of species and the composition was not different between Japanese cedar and cypress plantations. We repeatably confirmed 12 species within 2 orders and 9 families, including 10 resident birds and 2 summer species, across years and study areas, suggesting that they are the species which utilize coniferous plantations with high probability. Of those 12 species, 11 species were insectivorous. Furthermore, 10 of those species tended to build nests in trees or within tree cavities. Our results suggest that species with a high probability of utilizing coniferous plantations have high commonality with respect to food habits and nest site selection.

Soil scarification by heavy machinery is often applied to enhance regeneration of tall trees in dwarf bamboo grassland. The “replacement treatment”, which spreads the scarified debris to the treated area, is an alternative practice of standard soil scarification to contribute to growth improvement and generation from buried seeds. In this treatment, a deposition period has been set for the purpose of restraining the recovery of dwarf bamboos from rhizomes, but its appropriate period has not been examined. In this study, we compared regeneration of competitive vegetation and tree species among three different deposition periods (0, 2, and 12 months) in consideration of the pre-existence of tall forbs. The recovery of dwarf bamboos was restrained when the deposition period was long. On the other hand, the prevalence of a tall-forb, Fallopia sachalinesis in particular, which germinated from rhizomes increased when it had existed as previous vegetation, and only the 12 months deposition could prevent its dominance. The effect of the prolongation of the deposition period for the regeneration of tall-tree species was positive in Betula and Salix species and negative in Phellodendron amurense. However, the differences among the treatments were unclear where tall forbs had not existed. We conclude that a deposition period of 12 months is required for a site with pre-existing tall forbs, but the replacement without a deposition period can be applied for a site without tall-forbs.

The practice of forest education has spread, expanding the subjects of study. The concept has been organized for terms used in forest education and their definitions; but what the field of forest education covers has not been fully discussed. On the other hand, in the field of education, the basic concepts related to lifelong learning have been classified into formal, non-formal and informal learnings. This study aimed to ascertain what forest education includes based on this classification. Practices in each category were investigated by using the literature search method. The results showed that the field of forest education consists of five categories: 1) general education targeted at citizens, 2) specialized education targeted at specialists in forests and forestry, which are both formal education, 3) social education and forest extension targeted at citizens, 4) forest extension and vocational training targeted at specialists in forests and forestry, which are non-formal education, and 5) informal education including home education, targeted at citizens.

The forest environment transfer tax was been introduced in 2019 and is expected to support and facilitate municipal-level forest policies. The revenue from the tax can be used to promote utilization of timber and wood products and education in cities. Although forestry is not a main industry and forest policies are not active in urban municipalities, cities need to make relevant policies and implement the policies using the tax revenue. In this earliest stage of the new tax scheme, it is necessary to monitor the status of policy making and the plan for the policy implementation to improve the tax scheme for sustainable forest management with urban and rural municipalities. To identify the influence of the new tax scheme on municipal forest policies and ordinance-designated cities’ policies which are implemented using the revenue of the forest environment transfer tax, a questionnaire survey was conducted. As results, policies of promotion of timber and wood product use were detected as major policies. Compared with the prefectural-level policy trend, more diverse trends were detected in the policies of the cities. As a preliminary analysis result of background of their diversity, it was revealed that promotion of forest accumulation plans tends to be prioritized in the cities with relatively large forest lands per capita. The detailed analysis of the relationships between characteristics of the cities and their policies will be conducted in future research.

To promote domestic forestry smoothly in the future, understanding nonexperts' views on forestry and cutting methods is necessary. In the present study, we investigated an aesthetic (cognitive/evaluative) value of the nonexperts for the six types of cutting methods (clear-cutting, group cutting, old tree residual cutting, extensive residual cutting (100 pieces/ha), medium residual cutting (50 pieces/ha), small residual cutting (10 pieces/ha)) and before cutting. Then, we compared the aesthetic perspectives of the nonexperts regarding the methods and their application with those of the experts to evaluate their potential impacts on biodiversity conservation and rationality as forestry. According to the results, 1) nonexperts tended to rate clear-cutting and old tree residual cutting positively whereas group cutting with viewed with negative impacts. Besides, 2) because nonexperts are more likely to resist tree cutting, they should be furnished with information about the role of logging activities, and the need to take into account ecosystem functions and tree planting activities for final cutting. 3) There was a considerable gap between experts and nonexperts based on their perspectives on the roles of different final cutting methods, which implies that further efforts should be made to understand the perspectives of nonexperts to facilitate their education.

In recent years, candidate regions containing causative genes of Sosyun, a male sterility trait, have been identified by a linkage map in Cryptomeria japonica with quantitative trait loci analysis. Of which, reCj19250 was found to be closely linked to the causative gene in this candidate region. Another gene called reCj11611, which is presumed to be related to carbohydrate metabolism, was mapped to the same locus as reCj19250, but no details about this gene have been reported to date. In this study, the gene expression of both reCj11611 and reCj19250, or the monosaccharide and starch content, were investigated in C. japonica clones during pollen formation. The monosaccharide or starch content during pollen formation increased significantly in Sosyun, suggesting that carbohydrate metabolism is abnormal in plants with this trait. However, evidence that gene expression of reCj11611 is related to abnormal carbohydrate metabolism was not obtained. A specific mutation of the reCj11611 cDNA sequence associated with Sosyun was determined. Deletion of 20 bps sequences in the 3′UTR region for the reCj11611 cDNA sequence was applied to approximately 760 C. japonica clones using a DNA marker which was able to identify this deletion. Although six clones were shown to be heterozygotic for this gene, five of them were incongruent with the presence of reCj19250. Therefore, the genes cited to be in the same position on the C. japonica linkage map were, in fact, at neighboring loci.

The recovery of Sasa nipponica and regeneration of forest floor vegetation after a forest fire occurred in May 2015 were investigated in a larch (Larix kaempferi) plantation in the Ashoro Research Forest, Kyushu University. In July 2015 the coverage, height and biomass of recovered S. nipponica in the burned site were 83, 70 and 38％ of those in the unburned site, respectively. In July 2016 and 2017, the coverage, height and biomass of S. nipponica in the burned site were not significantly different from those in the unburned site. The number of herbaceous and tree species emerged in the burned site was almost twice as many as that in the unburned site in 2016. The number was not different in 2017, while the species composition in the burned site was quite different between 2016 and 2017. The results of PERMANOVA showed that the forest fire formed a different plant community composition compared to that before the forest fire and the difference was maintained at least for two years after the wild fire.

We planted large Sugi cuttings (160 cm tall on average) and characterized the breaking damage to the main stem and lateral branches caused by deer. Damage occurred primarily on the main stem in the first and second years, and on the lateral branches in the fourth year. While none of the trees died due to stem breakage during the study period, an increase in tree height was delayed in individuals with damaged stems. The average height of the site of damage was approximately 120 cm. The diameter at the position of damage ranged from 6.5 to 15.8 mm, and the shoot length above the damaged stem ranged from 17 to 85 cm. Slope gradient did not significantly affect the height of stem damage. The findings suggest that stems and branches thicker than 16 mm in diameter are unlikely to suffer due to the damage inflicted by deer. Nonetheless, if a deer fence is installed, maintenance of the fence should be undertaken regularly, as deer that get through the fence can cause extensive damage to young plantations.

Partial removal of leaves may alleviate drought stress under water-limited conditions in container-grown seedlings. We investigated the effects of removing 75％ of a plant's lateral branches on shoot water potential and xylem water conduction in container-grown Chamaecyparis obtusa seedlings before and after cessation of irrigation. All non-defoliated control plants died six days after irrigation ceased, whereas four out of the five defoliated plants with lower leaf mass survived and their water potential remained higher. Percentage of xylem embolism varied among defoliated plants probably because of exposure of xylem at the defoliating points. These results suggest that partial leaf removal causes slight unavoidable xylem embolism, but alleviates dehydration in seedlings according to the amount of leaf removal.

This paper summarizes the current status of lightning damage research: the relationship between topography and lightning/lightning damage, the relationship between tree species and lightning damage, the damage mode for single-tree damage and collective damage, and the mechanisms of damage. Many of these studies have used traces on the trunk as the evidence for lightning damage. Thus, a fundamental problem of lightning damage research is researchers' reliance on the subjective judgment of trace to determine the occurrence of damage, and lightning damage research could progress by accurately identifying the point where lightning strikes. The proposed mechanism that causes a trunk scar is the electrical resistance of the wood materials, but this has not been verified. The mechanisms of smoke generation and ignition have been considered but not specified, and the mechanism of damage can be identified and verified by making the process of lightning strikes on trees clear. Some researchers have used a technology that accurately identifies the location of lightning strikes and records the process of lightning strikes. Widespread use of these technologies would be a breakthrough in lightning damage research.