They were used to purify evils at tsuina no shiki (ceremony of driving out evil spirits) conducted in the Imperial Court on New Year's Eve, and made from reed stalk and peach tree.
大晦日に朝廷で行われた追儺（ついな）の式で、鬼を祓う為に使われた弓矢の事で、それぞれ葦（アシ）の茎と桃の木で出来ていた。