Wood identification of archeological materials and wooden heritages has provided useful information on the origin and historical background of the cultural heritage and sometimes provided a new perspective as well [1]. Wood identification has recently played an important role in the interpretation of wood selection for Buddhist statues from the late eighth century [2,3,4].
Japanese art historians have been discussing wood selection for Japanese Buddhist statues for many years. In the ancient period in Japan, the type of wood used for statues might have changed drastically from Cinnamomum camphora in the seventh century to coniferous wood in the eighth century. In 1964, Jiro Kohara who pioneered research on the scientific wood identification of wooden statues published the results of the wood identification of 682 Buddhist statues [5]. By several researchers, scientific wood identification of ancient wooden statues has been systematically conducted [2,3,4]. A hypothesis was proposed that the selection of Torreya nucifera for the eighth century statues is induced by Haku (cupressaceous wood in China) as an alternative to Santalum used in India for statues and that this selection might have been brought to Japan with the arrival of Tang monk Ganjin in Japan [2].
Buddhist statues have been investigated from various aspects. Compared to Buddhist statues, however, the study of Japanese Shinto deity statues has been comparatively behind [6]. Because Shinto deity statues tend to be enshrined behind closed doors as gods, this provided difficulties in investigating them. Thus a systematic investigation of deity statues has lagged behind and most deities have been studied only structurally, historically, and art historically.
Buddhist and Shinto deity statues are not contradictory objects, but Shinto deity statues should be contained within Buddhist statues [7]. Under the influence of Buddhism, traditional Japanese Shinto deities came to be expressed through statues [7]. The statue of deity in Japan is regarded to be made for the first time from Nara to early Heian periods with a flow of the syncretization of Shinto with Buddhism [8] and spread across the country. The influence of Buddhist statues can be seen in various aspects of early deity statues. Buddhist and Shinto deity statues, however, differ considerably in terms of style, because Buddhist statues are basically made to be worshipped by people and because their features are made unisexual. By contrast, Shinto deity statues are made as male or female deities and are enshrined behind closed doors. Identifying the wood species of Shinto statues will clarify their relationship with Buddhism.
This study focused on the wood selection of Shinto deity statues in Matsunoo-taisha [Matsu・no・o - taisha] Shrine, Kyoto, Japan worshiping a landlord deity and having a relatively weak contact with Buddhism [9]. Matsunoo-taisha Shrine includes several auxiliary/subsidiary shrines such as Shino-ōkami-no-yashiro-jinja Shrine, Koromode-jinja Shrine, San-no-miya-jinja Shrine, Munakata-jinja Shrine, Ichitani-jinja Shrine and Tsukuyomi-jinja Shrine [9]. Shinto deity statues have been handed down in this main shrine and these auxiliary/subsidiary shrines. Statues placed at auxiliary/subsidiary shrines have been on display in a new exhibition hall of the main shrine since 2010 [9]. When the new exhibition hall was opened, we conducted a wood sample collection together with Shiro Itoh, the director of the Wakayama Prefectural Museum. In this research, we applied the conventional preparation method and synchrotron X-ray microtomography (SRX-ray μCT) method [10, 11] for the wood identification of the wooden statues. SRX-ray μCT methods hold great potential, because of its nondestructive character. And samples could be reused for chemical and DNA analyses.