Beeches
Chinquapin oak / Castanopsis sieboldii / Sudajii / スダジイ
This member of the beech family is the most abundant and recognizable of the trees that make up Amami-Oshima’s broadleaf forests. The evergreen chinquapin is the botanical heart of the island’s ecosystem, comprising almost 80 percent of its natural forest. The tree can reach a height of up to 25 meters, and is easily identified by its resemblance to a giant stalk of broccoli. The bark is dark brown, and though smooth when young, becomes rough enough at adulthood to catch the seeds of epiphytes, “air plants” that grow on its surface. The leaves are wide and elliptical, and delicate yellow flowers appear on long stems from April to early summer. The blossoms emit a strong scent, attracting insects that help with the pollination of these trees as well as many wild birds that begin their breeding around this time. The fruit (or nut) of the chinquapin is small, usually less than 1 centimeter wide. These grow where they fall, and are also carried by animals and birds to other locations. Creatures in the forest rely on them for food, and they have been a staple of the human diet on Amami-Oshima since ancient times. The Japanese name of the tree is sudajii; it is also known on Amami-Oshima as shii.
Amami ring-cup oak / Quercus glauca var. amamiana / Amami arakashi / アマミアラカシ
This tree is a member of the Japanese oak family, and is found only in the Ryukyu chain. It likes limestone soil and is found everywhere from rivers and mangrove forests to the mountains, where it grows to heights of 5 to 20 meters. The trunk, which is covered with splotchy green and gray bark, grows straight up. Compared to other varieties of Japanese oak, the leaves are narrower, with serrated edges, hence its Japanese name arakashi (“rough oak”). The plentiful 3-centimeter-long nuts are an essential part of the diet for the island’s wildlife, including the Amami jay.
