Horsetail: Equisetum arvense
Parts Used: Arial Parts
Description: Horsetail is a primitive looking plant and indeed our common Horsetails are the descendants of ancient giant horsetails that once grew as tall as trees. It is a rather spindly looking plant. Equisetum arvense, as with all Horsetails, reproduces by spores rather than seeds and sends up separate fertile and infertile shoots. The fertile stems are produced in early spring, while the green, sterile stems start to grow after the fertile stems have wilted. It is the green, sterile stems with which we are most familliar and which are collected for medicine.
The straight green shoots of Horsetail are hollow and bear whorls of thin leaves fused into nodal sheaths. When Horsetail is picked and a plant turned upside down, it somewhat resembles a horse’s tail; hence the name. The sterile stems are approximately 10 to 80 cm tall and very small around, only 3-5 mm. Nodes appear along the stem, about 2 – 5 cm apart and this is where the whorls of side shoots branch off from the plant. Some species of Horsetail are unbranched or sparsley branched, but for this monograph we will be focusing on the common Field Horsetail, Equisetum arvense. The stems of Horsetails are coated with abrasive silicates, which gives the stems a rough feel, much like sandpaper. For this reason, some Horsetails are called “scouring rush” and have been used to scour or clean metal items. It is the silica content of Horsetail to which many of Horsetail’s healing properties are attributed.
Habitat: Different species of Horsetail grow nearly all over the world, with the exception of the Antarctic. It is believed, however, that Horsetails are not native to Australia, New Zealand or the Pacific Islands. I typically collect Equisetum arvense from moist soils near lakes, ponds and seasonally wet areas. Many Horsetails do prefer sandy, wet soils, though some prefer wet clay soils. Field Horsetail, Equisetium arvense is considered by some to be a nuisance weed. The shoots grow from rhizomes that are deep underground and are almost impossible to dig out.
Cultivation: Horsetail is rarely cultivated. It is more often considered a troublesome weed and so its growth is not encouraged.
Actions: Diuretic, Styptic, Vulnerary, Anodyne, Anti-nicoceptive, Anti-inflammatory, Anti-oxidant, Anti-microbial.
Energetics & Taste: Although Horsetail grows in wet soils, it is actually quite a dry plant. It does not taste too strongly and the fresh plant is slightly sour and drying. After the plant has dried, there is a distinct, subtle sweetness to the plant.
Constituents: Minerals: silicic acid and salicilates, potassium, calcium, aluminum, sulphur, magnesium and manganese; Phenolic Acid; Phenolic petrosins; Flavonoides: kaempferol, quercitin, apigenin, luteolin, genkwanin, isoquercitin; Phenolic glycosides (in the fertile stems); Glucosides: equisetumoside; Triterpenoides: isobouranol, taraxerol, germaanicol, ursolic acids, oleanic acid, betulinic acid; Alkaloids: nicotine, palustrine, palustrinine; Saponins: equisitonin; Phystosterols: cholesterol, epicholesterol, methylenecholesterol, isofucosterol, campestrol, Beta-sisterol
Uses: Every June, one of my harvesting priorities is to collect Horsetail and make a fresh glycerin tincture with it. Horsetail is a plant medicine with a wide variety of uses, including for skin and hair care as well as for joint, bone and cardiovascular health. Horsetail’s main claim to fame is its high content of silica which lends healing properties to all of the systems already mentioned.
Horsetail is a diuretic and so is well employed wherever diuretics are called for. It can be used as part of a herbal tea for urinary tract infection and also to help reduce swelling in joints. My first experience with Horsetail was in using a glycerin tincture of Horsetail to address painful and debilitating swelling in my right knee which had no apparent cause. This was a condition that had bothered me on and off and had been successfully treated several years prior by a chiropractor. After having three kids and then doing a lot of garden work the pain and swelling returned. This time I turned to herbs and Horsetail was recommended to me by a Mohawk healer, Kayanderes. I used the Horsetail glycerin tincture as a simple (the only herb I used) for about 3-4 months. I wasn’t always consistent with taking it everyday, but when I finally did become persistent about taking it, the pain and swelling completely resolved in about 2 months. At first I would forget to take the tincture whenever the pain started to subside. I would forget about it because I was not in pain, but then the pain and swelling would creep back in. Eventually I resolved to remember to take the Horsetail glycerite everyday, pain or no pain. After about 2 months of this I was pain free with no swelling. I stopped taking the Horsetail to see what would happen and the pain did not return.
Horsetail is exceptionally high in compounds that contain silica. Science has recently taken a great interest in silica and its role in our health. Silicon (Silicon is the name of the element as defined in the periodic table. Silica refers to naturally occurring chemical compounds which contain silicon bound to other elements, such as oxygen, for example, Si(OH)4) is not considered an “essential” nutrient, meaning that nutritional science does not consider that we need to get silicon in our diet. There are some scientists who are starting to question this, however. Silicon is present in the blood in concentrations similar to other physiologically important minerals such as iron, copper and zinc and is excreted in the urine in similar amounts as calcium, suggesting that silica has an important, if not essential biological role. In the body, silicon can be understood as an extremely important element for our structural integrity. Silica is an integral part of our blood vessel walls; it is essential in the body for synthesizing elastin and collagen and therefore helps to conserve the elasticity of our blood vessels. Silicon also appears to play a role in bone formation and bone health. Higher dietary silicon intake is associated with higher bone mineral density and studies have suggested that silicon is involved in bone formation and repair through the synthesis or stabilization of collagen. Collagen is the most abundant protein in the bone matrix and collagen is the body glue which makes up a good part of our connective tissue. Likewise, silica improves the health and elasticity of our skin and can also structurally improve our hair, skin and nails so that they are stronger and more vital. In the past it was believed that silica from solid foods was not absorbed by the body. There is now evidence to suggest that compounds which contain silica may be broken down in the digestive tract and absorbed.
Horsetail is also diuretic and astringent. This was previously assumed to also be caused by the silica in the plant, but recent studies have shown that these actions are more likely due to the flavonoids and saponins present in the plant. To me, this is a good demonstration of the benefits of using whole plant medicine rather than simply focusing on supposedly one active ingredient. Where Horsetail is concerned, we can see that some compounds of the plant have a role in eliminating excess water while other compounds are involved in repair of connective tissue, including bone.
Horsetail is a plant that comes to mind for chronic pain and inflammation; injuries to bone and connective tissue (fractures, sprain and strains); osteoporosis; cardio-vascular health, in particular strengthening and supporting the blood vessels and as a cosmetic to improve the health and appearance of the skin hair and nails. I rarely use Horsetail topically, although it is a styptic herb, meaning it helps to stop bleeding. This is due to the astringent tannins found in the plant. On a few occasions I have used Horsetail in a poultice applied to soft tissue injuries and minor cuts. Without a doubt, I employ Horsetail most often as a glycerin tincture made from the freshly harvested plant in June. Horsetail can also be dried and stored later for use in teas. When used as a tea, horsetail should be boiled for about 15-20 minutes to allow for the extraction of the silica.
Horsetail can be considered as part of a herbal treatment for any long term, chronic, painful, swollen conditions. It is not necessarily a plant that will immediately take away pain; rather it works slowly over time to help repair tissue that has become sore, swollen, damaged and painful. Where possible, it is also important to try to identify the root causes of the pain and treat that as well. If the pain is due to an injury that never healed properly, horsetail can help immensely over time with the healing process.
Chronic conditions, such as arthritis, which cause pain can be helped by horsetail as well, but dietary and digestive health should also be considered for treatment. Herbs that blend well with horsetail here include evergreens and comfrey applied topically as a salve as well as willows, poplars, birches or wintergreen as anti-inflammatories. Herbs that nourish and heal the nervous system work well with horsetail too, especially where an individual in pain cannot sleep due to pain and who may feel irritable because of chronic pain. Often, our irritation with constant pain can cause extreme anxiety, which disturbs sleep. Since sleep is when the body is busy healing, this whole process can turn into a vicious cycle. Choosing a nervine- ah herb nourishing to the nervous system- which is appropriate to the circumstance can help to induce sleep as well as relieve pain. Some herbs to consider here are Lousewort (Wood Betony or Pedicularis canadensis), Skullcap, Lemon Balm, Passion Flower and many more. Several years back when I first used Horsetail to address pain and swelling in my knee, I was not always consistent with taking horsetail everyday. One evening after neglecting the horsetail for a few days, my knee was particularly painful and swollen after a day of gardening. Even walking was difficult. I prepared a tea of Skullcap (Scutellaria laterfolia) and added in some horsetail tincture. I was just hoping that the skullcap would help me sleep while the horsetail began its slow healing process. However, after 2-3 sips of the tea, a sudden relief simply washed through my body like a wave and that pain was simply gone. That was one of the most profound lessons for me on the healing power ofhumble plants.
Horsetail should also be consideredfor those wanting to maintiain their cardiovascular health. One combination I like to use- as a glycerin tincture- is an blend of equal parts horsetail, horsechestnut seeds (Aesculus hippocastanum) and Hawthorn Berries (Cratageous spp). These herbs combine to nourish and tone the blood vessels, soothe varicose veins and make the heart beat more efficiently. Typically, Hawthorn is a mild herb that affects the heart and is safe for most people to take. It is, however, advised to consult with a traditional healer or herbalist before using Hawthorn.
If you are interested in using horsetail, it is a good herb to work with. It grows abundantly and is easy to gather and dry. Try to harvest from out of the way areas, away from roads, farm field and farm run-off if possible. Horsetail is good at taking up minerals from the soil and so it is best to collect it from as remote an area as possible. Although June is the ideal time to collect Horsetail, you can still collect and use it throughout the growing season.
R. Jugdaosingh, “Silicon and Bone Health“, J Nutr Health Aging. 2007 Mar-Apr, 11(2): 99-110.