Nasu in Autumn
Autumn comes early to the mountainous areas of Nasu, and fall flowers like the gentian species ezorindo bloom here as early as late August. By mid-September, the leaves of the Japanese rowan, Japanese oak, redvein maple, and other trees start to turn, reaching the height of color at the end of October. The migratory chestnut tiger—a stunning pale-blue, black, and russet butterfly found in montane zones in summer and fall—flutters among thistles and flowers of the daisy family. Other high-altitude blooms include monkshood, false snowparsley, and the clustered yellow heads of iwainchin, a type of chrysanthemum. The first snowfalls arrive in late October, and the hiking season ends in early November.
At lower elevations, beech nuts and acorns begin to ripen between September and November. They provide a feast for flying squirrels, Asian black bears, dormice, squirrels, and monkeys, and are a vital source of calories to survive the winter. On the outskirts of the forest, Japanese gentian is the last plant to flower in the region. Appearing in late September through October, its deep blue petals open fully in sunshine—distinguishing the plant from its relatives ezorindo and pasture gentian, which open only partially.
Winter migratory birds, such as the rustic bunting, brambling, Eurasian siskin, and hawfinch, begin to arrive from Siberia and other cold climes in mid-October. Lucky visitors may come across the green pheasant, Japan’s national bird, foraging in grasslands or harvested rice fields.
