Rattlesnake fern

A slow-healing wound or ulcer where the surrounding tissue looks pale and lax, calling for a gentle relaxant vulnerary poultice

A lingering dry, irritative cough in a person of generally weak constitution, where a mild demulcent pectoral is wanted rather than a stimulating expectorant

Overview. Botrychium virginicum, the rattlesnake fern, is a small, delicate fern of the adder's-tongue family found at the edges of open deciduous woods across eastern North America. It sends up a single divided frond partway along its stipe, topped by a distinctive tawny, grape-like fruiting spike. The whole fresh plant, and sometimes the root, was gathered by nineteenth century American folk and physiomedicalist practitioners, who classed it among the gentle relaxant remedies used for wounds and chest complaints, though it never became a mainstay of the materia medica.

Clinical Notes. This is a minor historical remedy rather than a plant in active clinical use today. Nineteenth century physiomedicalist writers, working within Cook's framework of relaxant, astringent and stimulant tissue effects, placed rattlesnake fern among the mild relaxant vulneraries, applied fresh or as a poultice to wounds and skin sores, and occasionally taken as an infusion for lingering coughs in people of weak constitution.

Properties and Uses. My attention was called to this plant by a farmer in central New York, who said its decoction would prove reliable as an antiperiodic. Preparing an ounce of the fresh plant in a pint of hot water, and giving two fluid ounces of warm infusion once an hour, it induced a gentle and warm perspiration, and soothed the nervous system.

Conservation. Locally uncommon in parts of its native range due to habitat loss and slow reproduction; wildcrafting is discouraged and it should not be harvested from wild populations.