Horsetail, more specifically field horsetail (Equisetum arvense), also known as horseweed or ponytail, is a herbaceous perennial plant found in the Arctic and temperate regions of the Northern Hemisphere.
Occurrence and cultivation of horsetail
Once established, the plant is resistant to drought and tends to grow invasively, which is why it is fought as a weed. Horsetail grows from a perennial rhizome that is widely branched and roots up to 50 cm deep. In spring, non-photosynthetic plant stems initially develop from underground buds of the previous year with up to 100,000 spores per stem. Only after these fertile stems wither do the characteristic spore-free shoots of the horsetail grow. The 10 – 90 cm long sterile stems, with 3 – 5 mm diameter and about 2 – 5 cm long movable segments, reach a growing height of up to 50 cm. Horsetail prefers moist soil in cropland and grassland. However, once established, the plant is resistant to drought and tends to grow invasively, which is why it is also controlled as a weed. At the same time, horsetail is considered an indicator of poor soil management.
Application and use
Except for field horsetail, all other species of horsetail are toxic. Field horsetail contains several substances that are prepared medicinally. The plant is rich in the minerals silicon (10%), potassium and calcium, as well as flavonoids, plant acids, saponoids and glycosides. These components have, in particular, an antioxidant and anti-inflammatory effect. Horsetail has the ability to accumulate gold as well as cadmium, copper, lead and zinc in its tissues. The accumulation of silica deposits in the stems gives horsetail its coarse and rough texture. Historically, therefore, horsetail was used to polish metal, especially tin. This is where the name tinweed is derived from. European horsetail contains the anti-allergy compound quercetin, which is generally absent in North America and Asia. In addition, the plant has small amounts of nicotine. For processing in teas, tinctures and wraps, as well as in cosmetics (active ingredient collagen), the upper 2/3 of the barren plant shoots are dried, cut and pulverized. To prepare an extract of horsetail herb, the herb is scalded and boiled to extract the silica. The cooled essence is filtered and can be mixed with a cream based on lanolin alcohol, for example, to make a healing ointment. Preparations from horsetail are available as capsules or in medicinal plant combination as tablets, dragées or drops. In Asia, the buds prepared like vegetables are considered a delicacy. Extracts of field horsetail make an effective fungicide for controlling stardust and rust on roses and mint. In biodynamic farming, horsetail is used to enrich the soil with silicon, which reduces the effects of waterlogging on plants.
Importance for health, treatment and prevention
Horsetail is known as one of the most valuable plant sources of silicon dioxide. Roman and Greek medicine already knew the effectiveness of this prehistoric plant and traditionally used horsetail to stop bleeding, heal ulcers and wounds, and treat tuberculosis and kidney disease. The natural silicon strengthens bones and protects the skin from wrinkles. It has a strengthening effect on connective tissue, is anti-inflammatory, skin tightening, promotes blood circulation and astringent. A horsetail rinse is also suitable for the care of oily hair. The improvement on bone density proven by a medical study is due to the fact that silicic acid is transformed into calcium in the body. Horsetail is traditionally used as a diuretic to rid the body of excess fluid through increased urination. Applications relate to the treatment of kidney and bladder stones, urinary tract infections, incontinence, and general kidney or bladder disorders. Almost every herbal preparation for drainage now contains components of horsetail. Horsetail is a clinically proven antioxidant and is used to treat edema, osteoarthritis and osteoporosis.A clinical study conducted in 2010 proved that an extract of horsetail can suppress free radicals and the growth of cancer cells. In home medicine, horsetail is used to treat chronic coughs as well as by direct application of the cooked herb to cure joint inflammation as well as rheumatism.