Which plant is known historically for its belief to expel spirits?

St. John's Wort has a rich history in herbal medicine and folklore, particularly for its use in warding off negative influences and expelling spirits. Its traditional applications often associated with beliefs in its protective qualities reflect a broader cultural view of plants serving not only medicinal purposes but also spiritual roles. This plant has been utilized over the centuries for various ailments, primarily related to mental health, such as depression and anxiety, but also in contexts where it was thought to provide mystical protection against malevolent forces.

In contrast, while the other plants listed have their own medicinal properties and historical uses, they do not share the same historical belief directly linking them to the expulsion of spirits or protective virtues. Milk Thistle, for example, is primarily known for its liver-protective properties, while Black Cohosh has often been used for its effects on women's health, especially menopausal symptoms. Cranberry is most recognized for its urinary health benefits, particularly in preventing urinary tract infections. None of these plants have the same historical context or associations with the belief in expelling spirits as St. John's Wort.