reed, is of red purple; the thin part of leaf is seaweed", which is similar to wakame, arame, kurome, or kajime (Ecklonia cava). The difficulty is that, at least in that time, kombu was not produced either in the East nor in the South China Sea. Moreover, following Zhang Yxi, Li Shizhen classified kūnbù and haidai (stands for kombu in Chinese) as different things, and this classification continues in China today. History The Erya (3rd–2nd century BC) noted that "Qūan resembles 綸 (lace, cord or rope). This is in the East China Sea." The Wupu Bencao (3rd century) mentions it as "Gūanbù, alias kūnbù". Tao Hongjing (456–536) noted kūnbù is edible. As previously mentioned, however, kūnbù can not be identified with kombu. Zhang Yuxi referred to haidai in the book Jiayou buzhu Shen Nong bencao (嘉祐補註神農本草; 1060). Although archaeological evidence of seaweed is hard to find because of its easy decomposition, some plant remains of wakame seaweed are found in some ruins of the Jōmon Period which leads to the supposition that kombu was also eaten at that time. As to surviving documents, the letters 軍布 (in Sino-Japanese reading 軍 is gun/kun; 布 is fu/pu/bu) appeared in Man'yōshū and wood strips from Fujiwara-kyō, and may have indicated kombu. The Shoku Nihongi (797) reports: in 797 of Emishi (Ainu or Tohoku region people) stated they had been offering up kombu, which grew there, as tribute to the Yamato court every year without fail. The Engishiki (927) also reports that kombu had been offered up by Mutsu. During the Muromachi period, a newly developed drying technique allowed kombu to be stored for more than a few days, and it became an important export from the Tohoku area. By the Edo period, as Hokkaidō was colonized and shipment routes were organized, the use of kombu became widespread throughout Japan. Traditional Okinawan cuisine relies heavily on kombu as a part of the diet; this practice began in the Edo period. Okinawa uses more kombu per household than any other prefecture. In the 20th century, a way to cultivate kombu was discovered and it became cheap and readily available. In 1867, the word "kombu" first appeared in an English-language publication—A Japanese and English Dictionary by James Curtis Hepburn. Umami, a basic taste, was first scientifically identified in 1908 by Kikunae Ikeda through his experimentation with kombu. He found that glutamic acid was responsible for the