Life in the Grasslands
The broad, sunlit slopes that surround Mt. Sanbe on its northern, eastern, and western sides are filled with flowering shrubs and grasses. Centuries of grazing livestock have prevented trees from growing in these areas, and their scenic beauty is one reason Sanbe was chosen for incorporation into Daisen-Oki National Park in 1963.
The grasslands support a very different ecosystem from that of the forest, where the passing seasons are marked by dramatic changes. In spring, the burgundy flowers of nodding anemone are first to appear amid the dry stalks of winter grass. The plant is called “old-man grass” (okinagusa) after the long, white stamens that sprout from its seeds, resembling an old man’s hair. By late spring, the coral blooms of Japanese azaleas appear in the grasslands. Cattle shun the poisonous plant, leaving the azaleas to spread freely over the mountainside.
In summer, the grasslands are covered in flowers—a beacon to pollinators such as the high brown fritillary. Blooming Chinese bellflower and golden lace dot the fields in autumn, and tall eulalia grass covers the area with long, tufted heads that sway in the wind. The dense leaves of eulalia grass serve as a haven for the tiny harvest mouse, which uses them to build spherical nests suspended between the stalks. Insects also make their homes among the grasses, and autumn nights are filled with the trilling of bell crickets and pine crickets. In the eastern grassland, the endangered horned dung beetle relies upon cattle dung both as a food source and a place to lay its eggs.
As livestock numbers have declined, Mt. Sanbe’s grasslands are slowly being reclaimed by the surrounding forest. Direct human involvement, such as seasonal grass-cutting and controlled burning of the western grassland, will continue to be necessary to maintain the ecosystem for future generations.
