"Tachibana" (Citrus tachibana) belongs to Rutaceae (the Citrus family). It is a small evergreen tree that is distributed from the Pacific side of Shizuoka prefecture of Honshu west to Shikoku, Kyushu in Japan, Taiwan and Jeju Island. It grows along the coast in warm regions and is the only citrus that grows naturally in Japan. From May to June, fragrant white flowers come on the tips of the branches. The fruits ripen yellow in winter, but they have a strong acidity and are not edible.