Abstract
Japanese red pine is a host of the mushroom, Tricholoma matsutake. This study aimed to optimize a method for guiding the growth of Japanese red pine roots to the soil surface to induce mycorrhizal formation in Tricholoma matsutake. A ground cover experiment was conducted in a forested area in which the mineral soil layer was exposed by scraping the topsoil. The scraping strength required to expose the mineral soil layer was clarified and the surface of the treated area was covered with a variety of substrates. Finally, the number of growing pine root tips at the soil surface was enumerated in the treated area. Consequently, a method involving covering the soil with nonwoven fabric and soil, or soil-filled sandbags, was found to be the most effective for guiding the growth of roots to the soil surface. Further trials are necessary to clarify the optimal scraping strength as this may vary depending on the forest environment.
