The effect of distance from neighboring Zelkova serrata canopy trees on the abundance of juvenile Z. serrata established in a conifer plantation was investigated in a heavily thinned plantation of Norway spruce (Picea abies L. Karst.) in Iwate Prefecture, northern Japan. The abundance of juvenile Z. serrata in the heavily thinned plantation was significantly higher than in an unthinned hardwood natural forest adjacent to Z. serrata canopy trees. Thinning and logging effectively promoted colonization of juvenile Z. serrata in the heavily thinned plantation. The mean abundance of Z. serrata juveniles decreased with distance from neighboring Z. serrata canopy trees. However, the local abundance of Z. serrata juveniles varied greatly, from 2,220 to 16,250 trees ha^-1, even when the distance from neighboring Z. serrata canopy trees was equal to less than 1.0 times the canopy height of neighboring Z. serrata trees.

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The Active Ranger (hereinafter referred to as AR) was introduced in June, 2005 in Japan. The primary objective of AR was to resolve labor shortage in national parks and have them serve as coordinators of various entities. In 2006 there were 65 ARs assigned mainly work related to national parks/wildlife protection in a total of 52 districts. ARs have been assigned to 25 out of all 28 national parks. In this study I investigated activities of AR in the Towada-Hakkoda Area of Towada-Hachimantai National Park, where they are engaged in administrative work, as well as the importance of such activities. As a result, I found that AR activities contribute greatly to onsite work. On the other hand, functions as coordinator do not appear to produce results.

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The system of selection cutting for Sugi (Cryptomeria japonica) forest, which was controlled by the Akita Regional Forest Offices before World War II, was well known to have caused dispute about its method of forest regeneration. The present study was done to investigate how this selection cutting method was applied to actual forest working areas, by analysis of historical materials. The three forest working areas investigated were Obiraki, Nibuna and Iwakawa. We found that the Sugi forest in each area had been managed by clear cutting and reforestration until 1924, but since the late 1920s the system had changed greatly to selection cutting with only natural regeneration. Thereafeter, despite criticism from many researchers resistant to the natural regeneration method, this working system was retained in the major forest working areas up to the end of World War II. However, the forest working plan for Iwakawa, which was established in 1940, noticed a need for compensatory planting in areas where Sugi regeneration had failed. After World War II, the method of forest regeneration in major working areas was reexamined.

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