Arrowhead is a plant growing in shallow water. The bulbs, 3-5 cm long, are peeled, boiled and seasoned. Often used in nimono, simmered dishes, such as Chikuzen-ni. Als part of Osechi-ryori, the festive cuisine for the New Year.
Kuwai is rich in proteins. The bulbs are quite soft but have little taste of themselves.
Kuwai are cultivated in Fukuyama (Hiroshima Pref.), Kyoto, Koshigaya (Saitama Pref.) and Hakui (Ishikawa Pref.).
[Kuwai. Photo Wikipedia]