Natural drying of standing Sugi trees by girdling treatment for fuel chip production

Abstract

Yukio Teraoka, Tsuyoshi Kajisa, Daisuke Higashi, Takashi Sonoda, Kiyomizu Maeda and Kunihiko Hata: Natural drying of standing Sugi trees by girdling treatment for fuel chip production. Jpn. J. For. Plann. 57: 37～44, 2024 Experiments to produce dried fuel chips by natural drying of standing Sugi (Cryptomeria japonica) trees using girdling treatment were performed. Ten trees were sampled from a 48-year-old stand for girdling that had been dried for 16 months, and five control trees without treatment were cut and chipped for each tree. The chip moisture contents (wet-based) were measured by the oven drying method and compared. Thus, nine girdling-treated trees had died from 3.5 to 13.5 months and could produce dried fuel chips with less than 42% moisture content. On the other hand, one girdling-treated tree had survived for 16 months, and the control trees showed high moisture content. Significant differences were observed between the moisture contents of died and survived trees by ANOVA. These results supported the feasibility of producing dried fuel chips from dead trees using girdling, which could be used for wood chip boilers.