"Hetsuka-nigaki" (Sinoadina racemosa) belongs to Rubiaceae (the Madder family). It is a tall decidous tree that is native to southern Shikoku, sothern Kyushu of Japan, and Taiwan. This tree grows in coastal forests and can reach 10-15 m in height. The bark is dark gray-white and furrowed fine longitudially when aging. The leaves are leathery, glossy, ovate-round and alternate with long petioles. The many, white-yellow tubular flowers bloom in the spherical capitulum from June to July. The corolla is quintuple-lobate shallowly at the tips and protrudes stamens.