Field Horsetail (Equisetum arvense L.)
Field horsetail (Equisetum arvense L.) is a native and widespread plant in many parts of North America, Canada, and Europe due to its prolific rhizome system. Nearly 2000 years ago, Pliny, the Roman naturalist, gave field horsetail the name Equisetum arvense. The botanical name is derived from the Latin equus, a horse, seta, a bristle, and arvens, of the field. Equisetum is the only genus in the Equisetaceae. The genus includes about 30 species. Horsetail has the ability to accumulate gold in its tissues as well as cadmium, copper, lead and zinc. Their stems contain high concentrations of silica and were once used to scour and clean various surfaces – hence the common name "scouring rush".
Field horsetail is a perennial with a spreading rhizome system. Like ferns, field horsetail does not produce flowers or seeds. This species reproduces by spores and more commonly by creeping rhizomes and tubers. They have two separate stages in their life cycle. The one is the spore producing stage, which includes the vegetative stems. The other is called a gametophyte that goes through the sexual part of horsetail's life cycle. The gametophyte requires a wet environment to survive. However, vegetative reproduction allows horsetail to wander into drier environments. Horsetail has a deep root system with rhizomes that can produce many terrestrial stems, giving it the appearance of a colony. Many of horsetail's ancestors grew as prehistoric trees (30 MYA) and contributed greatly to the formation of coal beds (Mitich, 1992).
Extracts of field horsetail make an effective fungicide and have been used to treat blackspot on roses and rust in mint. Dried horsetail is sold in some herb shops for the treatment of hemorrhage, urethritis, jaundice, and hepatitis in oriental traditional medicine. Horsetail tea is an ancient remedy that has retained the respect of herbalists for its soothing and curative effect on disordered bladders. The herbal-minded may take horsetail for dropsy and kidney complaints, ulcers of the urinary tract, or hemorrhages. Decoctions applied as a wash will help stop wounds from bleeding and ease inflammations, swelling, and various skin eruptions. Phenolic compounds in field horsetail act as natural antioxidants (Mimica-dukic, et al. 2008). The ethyl acetate-soluble extract of Equisetum arvense was found to exhibit distinctive hepatoprotective activity (Oh, et al. 2004). The polyphenolic compounds present in horsetail extracts are believed to possess activities that are responsible for their involvement in the treatment or prevention of platelet aggregation complications linked to cardiovascular diseases (Mekhfi, et al. 2004).
Mekhfi H. et al. (2004) Platelet anti-aggregant property of some Moroccan medicinal plants. Journal of Ethnopharmacology 94: 317-322.
Mimica-Dukic N, Simin N, Cvejic J, Jovin E, Orcic D, Bozin B. (2008) Phenolic compounds in field horsetail (Equisetum arvense L.) as natural antioxidants. Molecules 13(7): 1455-64.
Mitich, L. (1992) Intriguing World of Weeds: Horsetail. Weed Technol. 6: 779-781.
Oh H., Kim D., Cho J.H., Kim Y.C. (2004) Hepatoprotective and free radical scavenging activities of phenolic petrosins and flavonoids isolated from Equisetum arvense. Journal of Ethnopharmacology 95: 421-424.