Wholesale dealers’ homes would be decorated with an iron ring often used for halters that tethered horses to carts. These dealers not only purchased goods; they would also sell products, including kudzu, or Japanese arrowroot, a climbing vine of the legume family that grows rampantly in fields and mountains.

The kudzu from Kumagawa, which was renowned in Kyoto, is produced by soaking it in the cold and pure water of Kumagawa. This process results in high-quality kudzu starch, with its perfect translucent and sticky consistency. Kudzu was used to make traditional sweets and is also a prized ingredient in herbal medicines. Some people may have heard of kakkantō, an herbal medicine using kudzu known to counteract fevers, but it’s not actually commonly found in Kumagawa. Harvesting the kudzu roots is difficult as they can grow as thick as trees. Farmers must dig these up from the mountains and bring them back to the village, wash them repeatedly in the cold winter waters of Kumagawa, and in the end only 4% of the roots can be used to make the kudzu starch. Due to the scarcity and value of the product, most of it is taken to Kyoto. The only product you can find here in Kumagawa is a harsh-tasting, bitter kudzu called “kane,” which can also be used as an effective stomach medicine.