2024 Volume 33 Issue 1 Pages 1-7
Chinari Sakamoto, Keisuke Yamanaka: Snow damage to Japanese red pine, Pinus densiflora Siebold et Zucc., in a natural forest of Tottori University Hiruzen forest in December 2020. Ap. For. Sci.
On December 20 and 21, 2020, the snow damage occurred in a natural Japanese red pine forest, Pinus densiflora Siebold et Zucc., of Tottori University’s educational and research forest (Hiruzen) in Maniwa City, Okayama Prefecture. The Patterns and causes of damage were investigated. Japan Meteorological Agency data from the 19th to the 21st indicated moderate temperature fluctuations from -1 to 1°C, large snowfall, and light wind. It is presumed that these conditions, consistent with snow accumulation, caused the current snow damage. Eighty-seven percent of the damage was trunk breakage, and all was trunk rupture. The damaged trees had lower height, smaller diameter at breast height, and slender and shorter crowns. The characteristics were similar to those of snow-damaged Cryptomeria japonica D. Don. The fracture occurred at the trunk rather than the crown, and the presence of knots was confirmed in the wood near the breakage point in most of the damaged trees. Therefore, knots may influence trunk breakage. Pruning to reduce node size is effective in preventing tree damage. However, trees with high crown length ratios were damaged, and repeated weak pruning is recommended.
