nswort grows into dense patches that crowd out other species, there could be times when this weed is the only available forage in some pastures. Common St. Johnswort retains its toxic properties when dry, so animals can be affected by eating contaminated hay.
Facts and Folklore:
Hypericum' is Greek meaning 'over an apparition' referring to the ancient use of the herb to protect one from evil spirits.
The name 'perforatum' likely referred to the perforated look of the leaves.
The common name 'St. Johnswort' may be in reference to the time of flowering, which generally occurs around St. John the Baptist's Day (June 24).
In addition to many other medicinal properties, St. Johnswort is being studied as a possible treatment for AIDS. A chemical compound, called hypericin, isolated from leaves and flowers is capable of inactivating retroviruses such as Equine Infectious Anemia Virus (EIAV) and Human Immunodeficiency Virus (HIV).
An ointment of fresh common St. Johnswort flowers has been successfully tested as a treatment for first, second, and third degree burns.