Plants of Mt. Daisen
Ecologists have called Mt. Daisen a treasure house of rare plant species. During the last ice age, plants from the northern mainland spread south to the Mt. Daisen area. When temperatures rose, these species died out in the lowlands surrounding Daisen but were able to survive at the mountain’s higher elevations. Today, Mt. Daisen’s vegetation is a unique blend of species from Japan’s northern and southern regions, a balance of fragile ecosystems that vary markedly depending on the elevation.
The mountain has three basic vegetation zones: from its base to the area around Daisenji Temple (approx. 800 m), Daisen is covered in a mixed forest characterized by evergreen chinquapins, warm-temperate oaks, pines, Japanese cedars, and Japanese chestnuts. From there to an elevation of around 1,400 meters, the forest is composed mainly of Japanese beech and Japanese oak. Beyond 1,400 meters, around the sixth station of the summit trail, tall trees disappear and are replaced by shrubs and dwarf tree species, among them mountain willow and maple. On a plateau near the summit is an 8-hectare forest of Daisen dwarf Japanese yew, a variant unique to Mt. Daisen. As the largest concentration of dwarf yew in Japan, it was designated a National Natural Monument in 1952.
Like the Daisen dwarf Japanese yew, several other plants have rare variants that are native to the mountain. In early summer, the summit is graced with delicate flowers of the high-altitude species Daisen rhododendron (Rhododendron lagopus var. lagopus), Daisen St. John’s Wort (Hypericum asahinae), and Daisen honeysuckle (Lonicera strophiophora var. glabra).
