Differences in \u03b2-thujaplicin content of wood between plantation- and naturally grown Thujopsis dolabrata var. hondae (hinokiasunaro) trees in Shimokita Peninsula, Aomori, Japan

Yuya Takashima,Jun Tanabe,Jyunichi Ohshima,Shinso Yokota,Kazuya Iizuka,Futoshi Ishiguri,Hiroyuki Sanpe

doi:10.1186/s10086-019-1835-z

Abstract

β-Thujaplicin (hinokitiol) is an important extractive of Thujopsis dolabrata var. hondae (hinokiasunaro) that confers high durability to its wood. We investigated differences in β-thujaplicin content in wood from plantation- and naturally grown trees of T. dolabrata var. hondae, and also examined growth rate and wood density. A total of 29 trees were collected from two natural forests and a plantation forest in the Shimokita Peninsula, Aomori, Japan. β-Thujaplicin content was determined for each heartwood sample by gas chromatography. The content ranged from 0.29 to 3.67 mg/g (oven-dry weight basis). β-thujaplicin content of plantation-grown trees was significantly higher than for naturally grown trees, though with a large variation. The effect of radial growth rate on β-thujaplicin content was minimal. We conclude that T. dolabrata var. hondae wood from both plantation and natural forest has similar durability. The coefficient of variation of β-thujaplicin content in each stand was higher than for other wood properties. This degree of tree-to-tree variation in the trait suggests that promising production with more durable wood could be achieved by selecting T. dolabrata var. hondae trees containing a high content of β-thujaplicin for plantations.

Highlights

IntroductionThujopsis dolabrata (L.f.) Siebold et Zucc. var. hondae Makino (hinokiasunaro in Japanese) is an essential forestry species in Aomori, the northern part of Japan, because of its valuable wood [1–4]
Thujopsis dolabrata (L.f.) Siebold et Zucc. var. hondae Makino is an essential forestry species in Aomori, the northern part of Japan, because of its valuable wood [1–4]
Tanabe et al J Wood Sci (2019) 65:56 study [7], we showed that the differences in T. dolabrata var. hondae wood properties between plantation- and naturally grown trees tended to be small: there were no significant differences in basic density and compressive strength parallel to the grain; while the annual ring width of plantation-grown trees was double that of naturally grown trees

Summary

Introduction

Thujopsis dolabrata (L.f.) Siebold et Zucc. var. hondae Makino (hinokiasunaro in Japanese) is an essential forestry species in Aomori, the northern part of Japan, because of its valuable wood [1–4]. Hondae Makino (hinokiasunaro in Japanese) is an essential forestry species in Aomori, the northern part of Japan, because of its valuable wood [1–4]. Hondae has been used in the construction of Japanese traditional shrines and temples, and for applications that require durability, such as sill beams. The situation regarding wood production from T. dolabrata var. In Aomori, wood production of this species depends on natural forests managed since the 1800s by the selection thinning method to maintain this natural resource [1]. Wood production from natural forests has been decreasing for the past several decades because of a decrease in natural resources [5]. An increase in the area of T. dolabrata var. These plantations, in which T. dolabrata var. These plantations, in which T. dolabrata var. hondae exhibits faster growth rates than in the natural forests, will form the future supply of wood

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