To predict the yield of sugi (Cryptomeria japonica) plantations on a long rotation in private forests in Kagoshima Prefecture, the stand-density control diagram, site quality curve, and yield table were improved. The curvilinear equations required for the stand-density control diagram, including the full density curve equation, were also improved. Consequently, the new diagram may be more accurate than the existing diagram. The Mitscherlich function was applied as the site quality curve. Using the function, site quality was divided into three ranks. Using the average height of the dominant trees to decide site quality and the functions in the stand-density control diagram, the numerical values for the stand composition factor in the yield table were computed. Consequently, the stand-density control diagram, site quality curve, and yield table were shown to be correlated. The estimated numerical values of the stand composition factor in the yield table in this study were better than the values derived using the existing method. During long-rotation management of sugi plantations in our prefecture, improvement of the yield prediction information has been an important problem. The stand-density control diagram and yield table produced in this study should improve the efficiency with which the forestry engineers of our prefecture manage forest stands on long rotation.

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In Indonesia, the main factor behind forest clearance has been agricultural expansion, especially that of cash tree crops such as rubber and oil palm. This paper aims to clarify if forest loss due to conversion to rubber makes local people's poverty worse. We examine first, the relationship between the conversion of tropical forests to rubber and inequality of the local people's rubber field holdings and, second, the impact of land acquisition methods and the buying and selling of land on land ownership inequality, based on surveys of 160 randomly selected households in four rubber villages in Jambi Province, Sumatra. Data analyses suggest the following: 1) According to Lorenz curves for the area of rubber fields held by each village, the inequality of the villages' rubber field holdings increased according to the advance of forest conversion to rubber and that it continued to increase even after the forests had been completely converted and disappeared. 2) While forest-clearing was the main method of acquiring land while forests remained, rubber field expansion by purchase and intergenerational transfer increased as forest conversion advanced. 3) In the villages where the forests had disappeared, ownership of the villagers' land has steadily transferred to the rubber collectors through buying and selling and, as a result, land ownership inequality greatly increased such that a few exceptionally large rubber field holders appeared while many villagers became petty farmers.

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The following were identified in this analysis of the volume and transportation distance of wood products, i.e., ‘wood mileage’ in the Japanese sawmill industry. 1) In nationwide terms, the average wood mileage fell between 1962 and 1980, but has since risen steadily. 2) After 1980, the predominant tendency was for prefectures with larger average wood mileage to also show larger shipment quantities. 3) The dispersion of the average wood mileage among the prefectures fell from 1962 to 1980, but thereafter expanded. 4) The average wood mileage was influenced by changes in the round wood and wood products markets and the geographical distribution of sawn wood production capacity. It was pointed out that it is essential to analyze wood mileage paying close attention to developments in the wood products market and industry.

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High schools with forestry majors are currently reorganizing their departments. To discuss the future of their schools, the trends of careers after graduation, students' awareness about school life and the ways companies handle activities must be clarified. This paper reviews the results a survey of three such schools, seeking to understand the trends of career possibilities after graduation and use the questionnaire to grasp students' awareness about school life. We also interviewed forest owners' cooperatives to understand the connection between school education and the hands-on training of companies. Several issues were discovered. First, high schools with forestry majors seem to not be nurturing forestry mid-level technicians. Students who go on to special training schools are on the increase. Second, students who find jobs related to the forestry industry tend to feel the need to study further. The rest tend not to have such a motivation. Third, their school education is linked with the companies' hands-on training to a certain degree. Forest owners' cooperatives set a high valuation for graduates from these schools. It was thus found that it can be difficult for high schools with forestry majors to establish educational policies, because students experience complicated situations regarding their career of choice after graduation as well as their motivation to study more. Schools are now confronted with some difficult problems that include both responding to dynamic needs, as well as revising vocational education.

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A continuous vegetation profile covering a 600 km transect set up N-S across the boreal forest region of western Canada was obtained by airborne laser altimetry, along with ground-truth measurements of standing timber stock and biomass in a total of 47 forest stands located directly under the laser profiling flight course. Subsequently using these data, a mathematical model proposed to relate the vegetation profile with timber stock on the basis of the allometry principle was tested, resulting in a highly significant coefficient of determination of 0.74 between the profile area and standing timber stock. A comparison between the actually measured timber stock of half the ground-truth stands and the estimated counterpart based on a regression determined from the remaining half, also revealed a discrepancy of as little as 0.9∼4.5% in total timber volume. Finally, based on the regression determined from all the 47 ground-truth measurements, the distribution of timber stock all along the 600 km transect was estimated, in which the maximum stocking appearing toward south declined sharply further south and more gradually north in a southerly skewed distribution with an overall mean timber stocking of 136 m³/ha.

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To study the mode of inheritance of resistance to snow damage in sugi (Cryptomeria japonica), we crossed varieties that were resistant and sensitive to snow damage using a factorial design experiment. Progenies were investigated 10 years after the establishment of a progeny trial, and basal bending in the half-sib families of sensitive parents was found to be especially large. Regardless of the male parent, the mean basal bending was more than 100 cm in the half-sib families of the sensitive female parent. In basal bending, significant differences were observed between female parents, but not between male parents. The narrow-sense heritability in basal bending was 0.96. Furthermore, we estimated genetic gain using plural selection methods from all progenies. The genetic gain of basal bending was 60 cm. It was concluded that genetic improvement in resistance to snow damage using these crosses was effective.

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Root biomass and surface area were estimated using two methods in a broad-leaved secondary forest in southern part of Kyoto Prefecture. Root systems (n=6) were dug out as samples. Dry weights and diameters of all roots in each sample were measured in detail to establish allometric relationships for estimating root biomass and root surface area from stem-basal diameter. Using data from the DBH census in the study site in 1999, biomass and surface area were calculated for three size classes of coarse root. Sample soil blocks were taken to estimate biomass and surface area of small-diameter roots. Silhouette image analysis was used to measure surface area of roots with diameters less than 2 mm. Total estimated root biomass for the study site was 23.41 t ha^-1, and TR ratio (Top/Root) was 4.36. Total root surface area was estimated to be 3.50 m² m^-2, and 75% of root surface area was occupied by roots less than 2 mm in diameter.

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To develop a reforestation method for devastated land, the author investigated the behavior of seeds in clay pellets as reforestation materials in the Matsukisawa Basin in Ashio. In the case of a seeding density of 200 and 60 grains/m² with six tree species, the ratios of the third-year stem density to the seeding density were 2.5 and 3.7%, and stem density were 0.192 and 0.085 stems/m², respectively, with respect to the total of Pinus thunbergii Parl. and Pinus densiflora Sieb. et Zucc. It appears that reforestation by these two tree species may be possible using a seeding density of about 60∼200 grains/m² which is much lower than the previous seeding density, in the cases where the third-year stem density for reforestation is regarded as 0.4∼1.2 stems/m² based on the planting density.

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We discussed the characteristics of bark stripping occurrence and examined the reasons why cervids debark trees in this review. Cervids selected tree species in bark stripping, and the selection affected the forest composition. Although many reports mentioned that the bark stripping occurred in winter because of food shortage, some literatures proposed another reason for bark stripping occurred in seasons except winter. Though it was not proved experimentally, they mentioned that the reason for bark stripping might be remedying the rumen condition by eating bark. To explain the mechanism clearly, examinations of food habit and analyses of rumen condition with captive and wild deer are needed. The viewpoint on digestive physiology of ruminants may give us a novel idea on clearing up the food habits of cervids.

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