The effect of the nodes and their characteristics in Pinus thunbergii seedlings on the migration of the pinewood nematode, Bursaphelenchus xylophilus, were examined. We counted the number of nematodes that passed through stem-cuttings with nodes having different numbers of whorled branches (WBs) and those without nodes. Additionally, we studied the anatomical characteristics of the cortical resin canals (CRCs) at the nodes. We inoculated nematodes into seedlings of P. thunbergii to investigate the relationship between the number of WBs and symptom development. Fewer nematodes passed through the stem-cuttings with nodes than through the stem-cuttings without nodes, and these numbers decreased as the number of WBs increased. These results indicate that the migration of nematodes through the stem-cutting via the nodes is inhibited and the effect enhanced when WBs are more. The CRCs near the nodes were connected, and they curved at the base of the whorled branches. The number and size of the CRCs in the cross-section of nodes were smaller than those of CRCs in the cross-section of the stem away from the nodes. Such CRCs structures were promising as a factor for the inhibited the migration of the nematodes. The beginning of the foliage discoloration delayed in the seedlings with large number of WBs comparing to those with fewer WBs. This suggests that the inhibition of nematode migration at the nodes with many WBs may lead to the delay of the symptom development.

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Recently, the importance of RMZ has been recognized. However, systematized management methods for RMZ haven’t been established in Japan. We distributed the questionnaire to 24 forests that had obtained FSC certification, and 17 responses were received. In the questionnaire, respondents were asked about their RMZ. Most of them first developed RMZ at the time when they got certification, following the advices from their respective certification body and based on their own experiences. Many forests set 10 m or less wide RMZ along permanent streams, but the breadth was much narrower compared to overseas cases. Many forest managers intended to intergrade current conifer plantation into broad leaf forests and cared not to leave remainder materials within the RMZ. Although many respondents answered the desired effects have been achieved as a result of setting RMZ, nearly half of them also recognized the need for improvement in terms of scale or operation. It is necessary to accumulate more data and wide-ranging discussion in order to establish the appropriate RMZ. Considering its flexibility enough to respond to each forest situation or to management purposes, FPC is seemed to be an effective option of RMZ guideline.

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To determine the factors affecting the resistance of Japanese black pine mother trees to pine wilt disease, the time required for full browning and the water content of the branches obtained from 15 mother trees (clones) were analyzed. The time required for full browning of branch pieces inoculated with the pine wood nematode (PWN) Bursaphelenchus xylophilus ranged from 7.9∼19.3 days and significantly differed among 15 clones examined in this study (p<0.01). Because sampling direction and the position of the mother trees in the seed orchard had little effect on the browning of branch pieces, the time required for tissue degeneration was considered to be a property of the clone. The water content of branch pieces ranged from 116∼138% but did not significantly differ among the clones (p<0.05). The time required for full browning of branch pieces obtained from the mother trees significantly correlated with that from the seedlings of these trees (r_s=0.579, Spearman’s rank test; p<0.05); therefore, the property of degeneration of the mother trees was thought to be inherited by their seedlings. However, neither the time required for the full browning of branch pieces from mother trees nor that from their seedlings correlated with the degree of resistance of the seedlings, suggesting that the time required for tissue degeneration may not be an important factor influencing the resistance of a whole tree.

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In order to clarify the effect of dwarf bamboo (Sasa palmata) elimination on regeneration of hinoki cypress (Chamaecyparis obtusa), changes in the coverages of dwarf bamboo and regenerating trees were examined by aerial photographs taken from 1969 to 2005. Strip logging took place in 1967∼1969. In three of six logged strips, the dwarf bamboo was eliminated with herbicide (sodium chlorate) in 1969, weeded manually every year from 1977 to 1979 and herbicide (tetrapion) was applied again in 1980. The effect of herbicide which decreased dwarf bamboo was estimated lasting for approximately three years. In the remaining three strips dwarf bamboo was undisturbed (control treatment), and the control area has been covered with thick dwarf bamboo till 2005 except for the short term after the logging. In 2005, the regenerating trees covered about 24% of the control area, while they covered more than 70% of the treated area. There was a negative correlation between the coverages of dwarf bamboo in 1979 and regenerated trees in 2005. These results suggest that the elimination treatment of dwarf bamboo promotes the regeneration of hinoki cypress.

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We observed throughfall under evergreen coniferous (Cryptomeria japonica stands: large DBH, small DBH) and deciduous broad-leaved forests (Alnus inokumai stands) five times during snow cover periods (from December 24, 2008 to March 25, 2009) in the Yamagata experimental forest in FFPRI, Japan. The order of canopy openness values was Alnus inokumai>Cryptomeria japonica with small DBH>Crptomeria japonica with large DBH. The order of throughfall was the same as the canopy openness order. Throughfall in Almus inokumai stands was 119% greater than in Cryptomeria japonica with small DBH stands and 143% greater than in Cryptomeria japonica with large DBH stands, with integration over five measurement times. A highly positive linear relationship (R²=0.839, p=0.01) was found between canopy openness and throughfall in the Cryptomeria japonica with large DBH stand. A logarithmic relationship (R²=0.781, p<0.001) was found between canopy openness and throughfall for all data. These results suggested that clarification of the relative mixture of evergreen conifer and deciduous broad-leaved trees was important to the quantitative evaluation of the water balance in the Kamabuchi experimental watersheds.

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The stress-wave velocity (V_s) and Pilodyn penetration (P_p) were investigated for Sakhalin fir (Abies sachalinensis) plus-tree clones in three seed orchards of Hokkaido. The results of analyses in each seed orchard were similar to previous results in dynamic modulus of elasticity and basic density. The environment×genotype interaction of V_s and P_p was investigated by the ANOVA. V_s and P_p were significantly different among clones and seed orchards, as shown by the results of ANOVA. However, no significant difference was obtained for the environment×genotype interaction. The high correlation coefficients in product-moment and rank were obtained between the seed orchards in V_s and P_p. Therefore, the ranking of clones in V_s and P_p between the seed orchards showed a slight variation.

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Record of Commitments/Partnerships which is called Type 2 was adopted as a new concept of international negotiation at the Johannesburg Summit. Type 2 is voluntary initiative among governments, international agencies, civil societies and so on without negotiation. At the Summit, Japanese government launched Asia Forest Partnership which promotes sustainable forest management in Asia as Type 2. This report clarified reality of the Asia Forest Partnership on Phase I by literature research and interview to parties related. As a result, the Asia Forest Partnership was found contributing to build common awareness of sustainable forest management among partners as a framework of information sharing. However, about 80% of the partners were actually governmental, international agencies, and limited participations of civil societies and it was still a challenge.

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We investigated the occurrence of Bursaphelenchus xylophilus in wood samples derived from Pinus luchuensis trees that had recently died as well as from the adult Monochamus alternatus that emerged from those trees to determine if the pine mass mortality found on Miyako-jima Island, Okinawa Prefecture, is related to pine wilt disease. No Burusaphelenchus xylophilus was detected in any of the 796 wood samples collected at the 6 locations from 2002 to 2004, nor in 115 of the newly emerged adult M. alternatus, suggesting that B. xylophilus is not the causal agent of recent mass mortality of P. luchuensis on Miyako-jima Island. Bursaphelencus mucronatus, a closely related species of B. xylophilus, was detected in the wood samples collected at sites in the south-western part of Miyako-jima. This is the first recorded instance of B. mucronatus in Okinawa Prefecture.

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The germination capacity of stored seeds of Fagus crenata was tested to identify long-term (5+ years) storage conditions. Seeds with three different moisture levels (moisture content [MC] of 11.3, 6.1, and 4.0%) were stored at −20ºC. The percentage germination of seeds with 11.3% MC decreased after 4 years and reached zero after 6 years. Seeds with 4.0% MC maintained their germination capacity for at least 4 years, and seeds with 6.1% MC exhibited high germination percentages (60%) after 5 years of storage. Although the germination capacity began to decrease after 6 years, 25% of beech seeds showed some germination capabilities even after 10 years of storage. These results were supported by a follow-up experiment using seeds with 6.6% MC at −20ºC. In the follow-up experiment, seeds maintained high germination percentages (60%) after 7 years of storage. These findings indicated that the optimal MC of F. crenata seeds falls between 6% and 9%. The MC of seeds in the first experiment slightly increased (from 6.1% to 7.1%) at the end of 8 years of storage. Seedling malformation was observed in 8% to 25% of germinated seedlings after 4 years of storage; however, malformation did not affect seedling development. Further tests are required to confirm whether this seed storage method is widely applicable for seeds produced in the other distribution range of F. crenata.

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The number of abandoned coniferous plantations has increased greatly in recent year across Japan. However, though evapotranspiration greatly affects on available water resources, no study observing evapotranspiration in abandoned plantations has been reported. We observed canopy interception loss for four years in an abandoned coniferous plantation located in the Kasuya Research Forest of Kyushu University. Our results were compared with those obtained for other coniferous forests. The canopy interception loss ratio (interception loss/precipitation) we obtained was 24.9%. The relationship between stem density and interception ratio has previously reported. Indeed, the value we obtained was nearly that calculated based on that reported relationship; this information would be useful for examining whether the relationship derived from previous interception studies in coniferous plantations holds even for abandoned coniferous plantations.

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