Plant Community of Mt. Kirin
Mt. Kirin with an altitude of 195m and a forest area of over 60 ha has a unique mountain form of long diagonal rhyolite, making a sheer folding screen and penetrating into the Tsugawa layer of the Tertiary period. Tsugawa Castle was built in the medieval period, using this topography.
This mountain is also known as a treasury of plants; over one thousand species are estimated to be preserved here. This is an academically important plant community that represents a plant ecosystem of the Sea of Japan, going beyond that of Niigata Prefecture.
Plants on Mt. Kirin conceal interesting botanical facts. They include short plants, plants that grow large leaves and plants that have different hair on their leaves compared to the same species on the Pacific Ocean side. This may be because they had to adopt themselves to the deep snow.
Around the mountain top, luxuriate coniferous trees (red and white pines), and halfway down grow broad leaved deciduous trees (pin oaks, chestnut trees, Magnolia obovata, Mayr’s Maple and lindens) and evergreen trees (snow camellias and Japanese laurels). Trees and plants that color the four seasons are also abundant. The main trees that favor the cold climate on the Sea of Japan, alpine trees and trees that favor a warm climate are mixed. New species such as Tsugawa silver vines, Kirin tsukubane utsugi and shirobana koshi-no higan cherry trees have been discovered.