Self-heal is a low, creeping perennial of the mint family, native to Europe, Asia, Africa and North America and common through most temperate regions. Its squarish, often reddish stems carry pairs of blunt oval leaves and end in a dense, cylindrical spike of two-lipped purple flowers, with a pair of stalkless leaves standing out beneath it like a collar. It is plentiful in pastures, roadsides and waste ground, and can spread into dense mats and turn weedy in lawns. Its English names record its old standing as a wound herb: Gerard rated none better, saying the bruised herb alone made a healing salve, and Grieve gives an infusion as a general tonic and, sweetened with honey, as a gargle for a sore throat or ulcered mouth. Its Latin name is traced to the German word for diphtheria, which it was once used to treat. Peoples of the Pacific Northwest put its juice on boils, it is the xia ku cao of Chinese medicine, and its young leaves and stems can be eaten raw in salads. Folklore gave it two faces: the Irish held it so strong that nothing natural or supernatural could harm it and used it to cure a fairy-struck child, while English children were told it was the devil's and that he would carry off whoever picked its flowers. Kynes places it under earth and Venus, for clarity, healing, peace and release.