As the working-age population in Japan declines, many industries are now accepting foreign labor. This trend has extended to forestry, despite the lack of experience common in foreign workers. This study focuses on this trend. It reviews the systems governing the acceptance of foreign labor and examines the results and issues from the model projects implemented in Ehime Prefecture. The establishment of a skills-test system is essential for the introduction of technical intern trainees to forestry. The Forestry Skills Improvement Center was established in 2019 for this purpose, but it will take about five years to establish the skills-test system. It is considered essential to expand the organization and strengthen information transmission in these five years. According to the case in Ehime Prefecture, technical interns have high expectations for living in Japan, in terms of both earned wages and skill acquisition. While companies who accept foreign labor feel that the burden of providing technical guidance is not large, it has become clear that the cost of wage payment is considerable. Ultimately, since the acceptance period in the model project is one year, too short to acquire enough skills, it can be said that the results of skill transfer to overseas countries are limited.

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A nano-fibrillation process of bamboo resources to produce cellulose nanofiber was developed for future application to food materials. Bamboo pulp, which was prepared by soda cooking, was assisted by a commercially available cellulase derived from Aspergillus to allow smooth performance of the subsequent bead mill pulverization. In the bead milling, the diameter and speed of the zirconia beads in the milling vessel, and grinding time impacted the properties of the resulting microfibrillated pulp slurry. The progress of pulverization was confirmed with particle size distribution analysis, as well as the observation with a transmission electron microscope. Based on the morphology, particle size distribution, film strength, and friction characteristics, the pretreatment using a food additive Aspergillus-derived enzyme for pulverization using zirconia beads of 1-mm diameter was verified to provide bamboo cellulose nanofiber. No abnormality was observed on acute oral toxicity test, with an LD₅₀ value of >2,000 mg/kg in mice.

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Cryopreservation using liquid nitrogen is among the most useful and efficient methods for long-term storage of basidiomycetes fungal strains. However, there are still a limited number of reports on its efficiency in terms of the stability of intrinsic habits of the fungal strains. This study aims to understand the effects of frozen storage using liquid nitrogen on mycelial growth as well as the mycorrhization ability of Tricholoma matsutake strains. The mycelia of four strains of T. matsutake were preincubated on particles of autoclaved vermiculite immersed in nutrient liquid media in cryovials. The cryovials were filled with a cryoprotectant (to a final concentration of 5% DMSO and 10% trehalose) and then frozen to −80°C at a cooling speed of −1°C/min using a freezing container or a program freezer. They were then stored in gaseous liquid nitrogen at approximately −180°C in a locator cryogenic storage system for up to 3 years for one strain (Y1, identical to IFO33136) and 2 years for the other three strains. Following frozen storage, the regenerated mycelia were subjected to tests to investigate the hyphal extension rate on culture plates and mycorrhization abilities with red pine seedlings in vitro. All strains were viable after frozen storage with high survival rate, and formed ectomycorrhizal roots with the pine seedlings. The results indicate that frozen storage using liquid nitrogen can be an efficient method for the long-term stable preservation of T. matsutake and does not compromise both their mycelial growth and ectomycorrhization abilities.

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Soil fertilization in miniature seed orchards is important to ensure the growth and reproduction of seed trees, which are heavily damaged by seed production practices. A survey and physicochemical analysis of soil were conducted in miniature Cryptomeria japonica seed orchards at the Tohoku Regional Breeding Office, Forest Tree Breeding Center, FFPRI to determine the orchard soil properties before establishing procedures for standardized soil fertilization management. Soils were classified as typical brown forest soils and were generally rich in humus, poor in inorganic-N and available-P₂O₅ contents along with low degrees of base saturations compared with orchard and farmland soil values from previous reports. These results will be used to establish a concrete fertilization management plan for miniature seed orchards.

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Observations of precipitation and runoff have been conducted since the inception of the Takaragawa Experimental Watershed (Meteorological observation site: 36° 51' N and 139° 01 ' E ; MSL 816-1945 m). This report describes daily precipitation and runoff from 2001 through 2010. During this period, we modified water-level-discharge curve, installed meteorological instruments newly, and created geographic information system data for terrain and vegetation.

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