The former Toyooka-mura started to grow ebi-imo in earnest during the late 1950's, as the construction of Sakuma dam and Akiha dam at the upper reaches of the Tenryu river was completed and they did not have to worry about flooding as much as before.
旧豊岡村では、天竜川上流に佐久間ダム・秋葉ダムが完成したことから、洪水の心配が少なくなった昭和30年代初めに、本格的に栽培されるようになった。