Oakmoss derives its name from its favourite host tree, although it also grows on fruit trees, and occasionally even on pines. Confusingly, it isn't a moss, as the name would suggest. Instead, it is a kind of lichen, which makes it a symbiotic 'compound creature' composed of algae and cyanobacteria.
Oakmoss has never been used for food or medicine, yet it was well-known in the ancient world. The Egyptians used it to embalm the bodies of the dead and the Romans it as a perfume ingredient, which is how it is still used today. It features as a secret ingredient of several high-class perfumes. Essential oil manufacturers produce a resinoid, a concrete, but it is the absolute that is most highly valued.
Oakmoss has also long been used as a dye plant. When soaked in water and ammonia (traditionally in the form of urine) it yields a purple/magenta/pink dye, depending on the strength of the concentration.
Oakmoss has never played a role in herbal medicine but is used in aromatherapy, mostly as a fixative, and for its green, earthy scent.
In magical herbalism, Oakmoss is usually associated with Jupiter, because of Jupiter’s connection to Oaks. However, Oakmoss, and lichens in general, are distinctly Saturnine in colour, texture and essential nature. Oakmoss can be used in earth-honouring rituals and ceremonies to remember the dead.
Oak moss, Quercus lichen