Mustard greens are a plant belonging to the Brassica family. It originally grew naturally on the riverbank or roadside around Kawaura-machi. The seeds were used as an ingredient fo mustard, and local people ground the seeds and used them for dressing vegetables. However, in accordance with the widespread popularity of tube mustard, the number of people who use the vegetable has gradually decreased. Recently, the project of growing the vegetable as a local resource has been promoted among local farmers, and the Japanese mustard made from the seeds is now sold at local stands. In 2011, the mustard was commercialized, and it is now sold in roadside stations in the city. The mustard is mild and is becoming popular as a new specialty of Suzu City.