Moonwort
Moonwort is a magical and alchemical herb associated with the powers of the Moon. Moonwort, whose genus name is Botrychium lunaria, is a species of grape fern, so-named because the plants bear grapelike clusters of spore cases. Moonwort leaflets are shaped like crescent moons.
In English lore dating back as far as the 16th century, moonwort, found upon the heaths, has the power to open IRON locks and pull the iron shoes off horses. The country folk of the 17th century called moonwort Unshoo the Horse. A story goes that the Earl of Essex’s horses, grazing on the White Down in Devonshire, lost 30 shoes after treading upon moonwort.
Witches were said to love it, for iron repelled them, but with moonwort they could easily get past the iron Amulets and locks of any home or stable that they wished to enter. In Alchemy, moonwort is probably the “white herb” prized by alchemists in the belief that it possesses a celestial vitality. It represents the white, or albedo, stage of the Great Work. The “white herb growing upon small mountains” is cited in the writings of Maria Prophetessa.
From :The Encyclopedia of Magic and Alchemy Written by Rosemary Ellen Guiley Copyright © 2006 by Visionary Living, Inc.