2020 Volume 102 Issue 5 Pages 300-305
As a method for reforestation, the effect of scarification that removes dwarf bamboos by using heavy machinery has widely been confirmed. However, in locations where the use of heavy machinery is restricted (such as steep slopes), appropriate practice based on natural regeneration has not yet been established. In this study, we therefore attempted to conduct scarification using a brush-cutter to enhance natural seed regeneration through disturbing the surface soil layer. In addition, we introduced a practice to cut the rhizome at periphery of the scarified area using a root cutter, expecting to block recovery of dwarf bamboos from their ramet spread around the area. The scarification using brush-cutter was clearly effective to increase the occurrences of tree seedlings. The rhizome cutting could suppress the recovery of dwarf bamboos to about half in the third year after the treatment, and seemed to contribute to higher survival of tree seedlings. The man-powered scarification and rhizome cutting treatment were performed realized by adding respectively 38％ and 24％ of the cost compared with the standard site preparation for seedling-planting. Since the scarification using a brush cutter is for an unintended use, it is necessary to develop equipment that can ensure safety for practical use. However, this study shows the possibility of new options for natural regeneration in a forest having a dwarf bamboo understory.
