According to 'Somin Shorai' (Japanese old story and the folk religion originating in the story) in "Bingo no Kuni Fudoki" (unknown or lost writing) quoted in "Shaku Nihongi" (annotated text of the Nihon Shoki) (Kanekata URABE, the mid Kamakura period), a kaya grass ring was worn on the waist to avoid disasters, and it was believed that the strong vitality of kaya grass had the mysterious power of preventing disasters.
『釈日本紀』（卜部兼方　鎌倉時代中期）に引用された『備後国風土記』逸文にある「蘇民将来」神話では茅の輪を腰につけて災厄から免れたとされ、茅の旺盛な生命力が神秘的な除災の力を有すると考えられてきた。