There have been a number of studies focusing on shrine/temple forests as valuable urban green spaces with public benefit functions such as recreation, environmental mitigation, and ecosystem conservation. On the other hand, few studies have been conducted on social backgrounds, institutional frameworks, and management policies of shrine/temple forests. In this study, we examined the management policies of shrine/temple forests in Kyoto from the late Meiji to Taisho periods (1903-1926), when the management system of shrine/temple forests were established after the Meiji Restoration. This study reviews the relevant national laws and regulations, administrative responses from Kyoto Prefectural Government, and individual forest management plans created for specific shrine/temple forests. Results revealed that the national government and the Kyoto Prefectural Government established management policies that conserve the functions of those forests based on the understanding that shrine/temple precinct forests are for landscape preservation, while outside of shrine/temple precinct forests are for production of forest products. However, individual shrine/temple forest management plans indicated that some part of shrine/temple precinct forests also functioned as resource production. The results have shown that both inside and outside of shrine/temple precinct forests maintained their functions of landscape preservation and production of forest products simultaneously by implementing adaptive management practices that align with internal and external requirements.

Although the demand for domestic lacquer has recently increased, few studies have reported how to establish and manage a lacquer tree plantation for maximizing the yield of lacquer. Currently, lacquer tree resources are managed based on the number of trees. However, the size distribution in the stand rather than the number of trees should be used, as the yield of lacquer per tree depends strongly on trunk diameter. Furthermore, the survival ratio should be considered, as the species is shade-intolerant and shaded trees die easily due to density effects. Here, a prediction model for the diameter-size distribution based on Y-N theory was constructed using data from 49 lacquer tree stands in northern Iwate and southern Aomori. The parameters A and B of the Y-N curve, as well as the survival ratio after planting, were assumed to be a function of the overstory height of the stand (Hc). The effect of planting density (PD) and the site quality index (SI) were evaluated for these functions. SI was obtained from an SI curve based on the relationship between stand age and Hc. We estimated the yield of lacquer per stand by substituting the yield of lacquer per tree with respect to trunk diameter, which was previously reported for the predicted distribution. Then, the maximum yield of lacquer per stand was evaluated with different PDs and SIs.

Sugi (Cryptomeria japonica) is planted in a wide range of areas and environments. Understanding clone × site interactions (genotype-environment [GE] interaction) for the improvement of target traits in forest tree breeding is essential for accurate evaluation of the genetic performance of clones and effective diffusion of improved clones. However, there are a limited number of tests of GE interactions for survival traits compared to those for growth traits of Sugi. In the present study, we conducted an integrated analysis of long-term data of tree height, diameter at breast height and survival rate from 37 Sugi clonal test sites. We evaluated the GE interactions and temporal changes of growth and survival traits. The results showed that the GE interaction was generally small for growth traits, and the rank of clones was generally similar among test sites. The GE interaction also tended to be larger as trees grow. On the other hand, the survival rate exhibited larger GE interaction than the growth traits, and the rank of clones was less similar. These results suggest that, in addition to the risk of GE interaction for survival traits, it is necessary to consider local adaptability in mature stage for growth traits when selecting clones to plant.

Forest resources in Japan underwent a drastic decline by the early Edo period, and it is reflected by a decrease in abundance of natural sugi cedar (Cryptomeria japonica) trees in the Akita region. To understand the process contributing to this decline, we conducted pollen analysis of the sediments from the Kamiyachi mire at the foot of Mt. Moriyoshi, Akita Prefecture, and reconstructed the vegetation history around the mire. From the age corresponding to the lowermost sediment up to the present, this area has been covered by a temperate deciduous broadleaf forest dominated by beech and oak trees. Sugi cedar was dominant, along with temperate deciduous broadleaf species, until the early 900s. Subsequently, the mid-900s to the 1200s, levels of Cryptomeria pollen underwent a slight decrease, and then decreased more drastically after the 1300s. The contributing factor to the decline in the abundance of sugi cedar is human activities. The decline in the abundance of Akita-sugi trees lasted from the mid-1500s through the mid-1800s. Subsequently, findings from the uppermost sediment layers, Cryptomeria pollen increased and became dominant again. This change was due to the plantings of sugi trees. Decreasing processes from dominant in the forest were slightly different respectively in the three sites compared. We attribute these differences to location-specific factors of each sugi stand such as distance from the nearest village.