Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Environmental influence on wood quality. I. Distribution and amount of compression wood within the stems of young sugi and hinoki trees grown in a heavy snowfall district.

Abstract

The distribution of compression wood (CW) was studied in sugi (Cryptomeria japonica) and hinoki (Chamaecyparis obtusa). Two varieties of sugi were used: okinoyama-sugi, which grows in western Japan and is adapted to snow, and boka-sugi, which grows in central Japan. Boka-sugi trees showed large stem curvature of both basal sweep and stem sweep types due to snow creep on the slopes, and also had a high content of CW on both downhill and uphill sides of the stem. Okinoyama-sugi had only slight stem curvature and less CW than boka-sugi. Hinoki trees showed different amounts of stem curvature on gentle vs. steep slopes, but little difference in CW content. This is ascribed to an intensive training method called yuki-okoshi, used on steep slopes, which reduces curvature and excessive CW formation. In 4- to 15-yr-old stems, there was a positive correlation between amount of CW formed each year and annual rainfall (r = 0.45-0.85).