Mercury

Herbs, trees, flowers and fungi appear throughout the correspondence traditions: assigned to planets and signs, used in incense and ritual, and catalogued in the herbals. Astrological herbalism, in which a plant's ruling planet indicates its medical and magical use, is set out by writers such as Nicholas Culpeper, whose seventeenth-century herbal keyed English plants to the planets that governed them.

A plant may carry a planetary and elemental rulership, a place in ritual and incense, a folkloric virtue, and a medicinal use, and the atlas records these several dimensions of the plant lore of many traditions.

The uses of plants in the traditions overlap and diverge: the same herb may be a planetary remedy in astrological medicine, an ingredient of ritual incense, a protective charm in folklore, and a sacred plant in a particular cult. The atlas keeps these uses distinct and presents the historical and folkloric material as tradition rather than as medical guidance.

The atlas gives each plant its correspondences, its ritual and folkloric uses, and its associations. The planets and signs that rule the plants, and the incense they are burned in, are treated in their own categories.