An old growth evergreen forest extends around the tip of Manazuru Peninsula, located in the southwestern corner of Kanagawa Prefecture, Japan. The forest, traditionally called "Ohayashi", originates from a pine plantation in the early Edo period, and it has been protected by the Forest Law as well as the Prefectural regulations. Since decades ago, however, old growth pine trees (Pinus thunbergii and P. densiflora) in the forest have been suffered from pine wilt disease. The mycoflora of the

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... st has only partially been known, and understanding the diversity of pine ectomycorrhizal fungi is of particular importance for sustainable forest management in that site. We investigated the seasonal occurrence of fungal fruitbodies in the "Ohayashi" forest and a Japanese red-pine (P. densiflora) forest in Mt. Nangoh, located near Manazuru Peninsula. We also examined the growth of pine ectomycorrhizae in the Ohayashi forest. Our investigations were carried out by local citizens including school children and teachers, and volunteer stuffs of Kanagawa Prefectural Museum of Natural History and the Manazuru Shell Museum. We collected 129 fungal species, which consists mainly of macrofungi, and six myxomycete species in the Ohayashi forest. Among them, only one species (i.e., Suillus bovinus) was undoubtedly ectomyrorrhizal with pines. On the other hand, 58 fungal species and two myxomycete species were recorded from Mt. Nangoh. Seven of the fungal species in Mt. Nangoh were ectomyrorrhizal with pines, occupying ca. 13% of the total fungal species at the sites. In the Ohayashi forest, formation of ectomyrorrhizae was observed from about 30-73% of root tips in soil blocks collected under P. thunbergii trees, suggesting that quite a few ectomycorrhizal fungi were still viable even where the occurrence of mushroom fruitbodies was rare. We suggest that a procedure to activate ectomycorrhizal formation using charcoals or other similar materials can promote the pine tree growth and the protection from the pine wilt disease. Therefore, the procedure can contribute to proper forest management in Manazuru Peninsula.