Botanical Name : Equisetum fluviatile
Species: E. fluviatile
Synonyms: E. heliocharis. E. limosum.
Common Name : Water horsetail , Swamp Horsetail
Habitat : Equisetum fluviatile is native to arctic and temperate Northern Hemisphere, from Eurasia south to central Spain, northern Italy, the Caucasus, China, Korea and Japan, and in
North America from the Aleutian Islands to Newfoundland, south to Oregon, Idaho, northwest Montana, northeast Wyoming, West Virginia and Virginia.. It grows on shallow water in lakes,
ponds and ditches and other sluggish or still waters with mud bottoms.
Equisetum fluviatile is a herbaceous perennial plant, growing 30–100 cm (rarely 140 cm) tall with erect dark green stems 2–8 mm in diameter, smooth, with about 10–30 fine ridges. At
each joint, the stem has a whorl of tiny, black-tipped scale leaves 5–10 mm long. Many, but not all, stems also have whorls of short ascending and spreading branches 1–5 cm long, with the longest branches on the lower middle of the stem. The side branches are slender, dark green, and have 1–8 nodes with a whorl of five scale leaves at each node. The water horsetail has the
largest central hollow of the horsetails, with 80% of the stem diameter typically being hollow. The stems readily pull apart at the joints, and both fertile and sterile stems look alike.
The water horsetail reproduces both by spores and vegetatively by rhizomes. It primarily reproduces by vegetative means, with the majority of shoots arising from rhizomes. Spores are
produced in blunt-tipped cones at the tips of some stems. The spore cones are yellowish-green, 1-2 cm long and 1 cm broad, with numerous scales in dense whorls.
It is hardy to zone (UK) 2. The seeds ripen from Jun to July.
Prefers a moist soil with a pH between 6.5 and 7.5. Plants are hardy to about -30°c. Plants have a deep and penetrating root system and can be invasive. If grown in the garden they are best kept in bounds by planting them in a large container which can be sunk into the ground.
Spores – best collected as soon as they are ripe in the spring and surface-sown immediately on a sterile compost. Keep moist and pot up as soon as the plants are large enough to handle. Very
difficult. Division. The plants usually spread very freely when well sited and should not really need any assistance.
The water horsetail has historically been used by both Europeans and Native Americans for scouring, sanding, and filing because of the high silica content in the stems. Early spring shoots were eaten.
Strobil (the fertile shoots in spring) – cooked. Used as an asparagus substitute, though it is neither palatable nor nutritious. Caution is advised, see the notes above on toxicity. Roots – cooked.
The roots contain a nutritious starch. Caution is advised, see the notes above on toxicity.
Medically it was used by the ancient Greeks and Romans to stop bleeding and treat kidney ailments, ulcers, and tuberculosis, and by the ancient Chinese to treat superficial visual obstructions. Horsetails absorb heavy metals from the soil, and are often used in bioassays for metals.
Horsetails have an unusual chemistry compared to most other plants. They are rich in silica, contain several alkaloids (including nicotine) and various minerals. The plant is styptic. The
barren stems are used, they are most active when fresh but can also be dried and sometimes the ashes of the plant are used. A decoction applied externally will stop the bleeding of wounds and
Other Uses: Rootstocks and stems are sometimes eaten by waterfowl.
Large quantities of the plant can be toxic. This is because it contains the enzyme thiaminase, a substance that can rob the body of the vitamin B complex. In small quantities this enzyme will do no harm to people eating an adequate diet that is rich in vitamin B, though large quantities can cause severe health problems. The enzyme is destroyed by heat or thorough drying, so cooking the plant will remove the thiaminase. The plant also contains equisetic acid – see the notes on medicinal uses for more information.
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.