Abstract
Many members of Pteridophytes have been traditionally used in the designs of Japanese gardens and a large variety of ferns attract gardeners as greening pieces in the garden designs. However, details or examples of practical uses of ferns in traditional gardening in Japan have only rarely been introduced in non-Japanese literatures to date, despite the importance of ferns in Japanese gardening traditions. In addition to the discussion of ferns in gardening, the use and association of these plants in Japanese agricultural and horticultural sceneries are addressed. The presence and importance of 40 familiar fern species in local gardening, agricultural and horticultural ecosystems are also discussed, as well as the roles of introduced ferns as key elements of ecosystems and their interaction with neighboring biota. Finally, some examples of uses of fern species in environmental science and engineering are also reviewed.