Subtropical Plants on Aoshima
The distinctive vegetation on Aoshima includes tropical and subtropical plants that rarely grow this far north. The plants thrive on the island due to its mild climate and high annual rainfall, mainly caused by the warm Japan Current that flows from the East China Sea, past Aoshima, and northeast through the Inland Sea along the Pacific coast of Japan. Of the 226 species of plants on the island, 27 are tropical or subtropical and designated a Special Natural Monument of Japan. The most common of these is the biro or fountain palm (Livistona chinensis), which grows all over Aoshima. It has been identified with the island for centuries. Some of the approximately 5,000 biro trees are up to 350 years old. Other noteworthy plants on the island include the poisonous kuwazuimo (Alocasia odora) taro, the hamayu (Crinum asiaticum) spider lily, and the sharinbai (Yeddo hawthorn; Rhaphiolepis umbellata).