The leaves of the yarrow are placed over the eyes, and thus will allow someone
to see into the Otherworld. The stems, when dried, can be used for divinatory
purposes by holding them in your hand and casting them.
Celtic folklore holds that witches could achieve flight by wearing a sprig of
the yarrow plant within their cap, which is called a Cappeen d'Yarrag. The
yarrow herb was also described as having strong healing powers which was probably
based in the belief that it had the ability to banish negative forces.