Nettle

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Nettle
Stinging nettle (Urtica dioica)
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Rosales Family: Urticaceae Genus: Urtica L.
Species
See text.

Nettles redirects here. For the British actor, see John Nettles. For the former New York Yankee baseball player, see Graig Nettles.

Nettle is the common name for any of between 30-45 species of flowering plants of the genus Urtica in the family Urticaceae, with a cosmopolitan though mainly temperate distribution. They are mostly herbaceous perennial plants, but some are annual and a few are shrubby.

The most prominent member of the genus is the stinging nettle Urtica dioica, native to Europe, north Africa, Asia, and North America. The genus also contains a number of other species with similar properties, listed below. However, a large number of species names that will be encountered in this genus in the older literature (about 100 species have been described) are now recognised as synonyms of Urtica dioica. Some of these taxa are still recognised as subspecies.

Most of the species listed below share the property of having stinging hairs, and can be expected to have very similar medicinal uses to the stinging nettle. The sting of Urtica ferox, the ongaonga or tree nettle of New Zealand, have been known to kill horses, dogs and at least one human.

The nature of the toxin secreted by nettles is not settled. The stinging hairs of most nettle species contain formic acid, serotonin and histamine; however recent studies of Urtica thunbergiana (Fu et al, 2006) implicate oxalic acid and tartaric acid rather than any of those substances, at least in that species.

Contents 1 Species of nettle 2 Uses 3 Safety 4 Popular culture 5 See also 6 Similiar plants 7 External links and references 8 References

[edit] Species of nettle

Species in the genus Urtica, and their primary natural ranges, include:

• Urtica angustifolia. China, Japan, Korea.
• Urtica ardens. China.
• Urtica atrichocaulis. Himalaya, southwestern China.
• Urtica atrovirens. Western Mediterranean region.
• Urtica cannabina. Western Asia from Siberia to Iran.
• Urtica chamaedryoides (heartleaf nettle). Southeastern North America.
• Urtica dioica (stinging nettle or bull nettle). Europe, Asia, North America.
• Urtica dubia (large-leaved nettle). Canada.
• Urtica ferox (ongaonga or tree nettle). New Zealand.
• Urtica fissa. China.
• Urtica galeopsifolia. Central and eastern Europe.
• Urtica gracilenta (mountain nettle). Arizona, New Mexico, west Texas, northern Mexico.
• Urtica hyperborea. Himalaya from Pakistan to Bhutan, Mongolia and Tibet, high altitudes.
• Urtica incisa (scrub nettle). Australia.
• Urtica kioviensis. Eastern Europe.
• Urtica laetivirens. Japan, Manchuria.
• Urtica mairei. Himalaya, southwestern China, northeastern India, Myanmar.
• Urtica membranacea. Mediterranean region, Azores.
• Urtica morifolia. Canary Islands (endemic).
• Urtica parviflora. Himalaya (lower altitudes).
• Urtica pilulifera (Roman nettle). Southern Europe.
• Urtica platyphylla. China, Japan.
• Urtica pubescens. Southwestern Russia east to central Asia.
• Urtica rupestris. Sicily (endemic).
• Urtica sondenii. Northeastern Europe, northern Asia.
• Urtica taiwaniana. Taiwan.
• Urtica thunbergiana. Japan, Taiwan.
• Urtica triangularis
• Urtica urens (dwarf nettle or annual nettle). Europe, North America.

The family Urticaceae also contains some other plants called nettles that are not members of the genus Urtica. These include the wood nettle Laportea canadensis, found in eastern North America from Nova Scotia to Florida, and the false nettle Boehmeria cylindrica, found in most of the United States east of the Rockies. As its name implies, the false nettle does not sting.

There are many unrelated organisms called nettle, such as:

• Dead-nettle (Lamium spp.) and hedge-nettle (Stachys spp.) which are in the Lamiaceae or mint family.
• Devil's nettle, which is another name for yarrow.
• Carolina horsenettle (Solanum carolinense) in the Solanaceae.
• Spurge-nettle (Cnidolscolus stimulosus) in the Euphorbiaceae.
• Sea nettle (Chtysaora quinquecirrha) which is a jellyfish.

Nettles are the exclusive larval food plant for several species of butterfly and are also eaten by the larvae of some moths including Angle Shades, Buff Ermine, Dot Moth, The Flame, The Gothic, Grey Chi, Grey Pug, Lesser Broad-bordered Yellow Underwing, Mouse Moth, Setaceous Hebrew Character and Small Angle Shades. The roots are sometimes eaten by the larva of the Ghost Moth Hepialus humuli.

[edit] Uses

Nettle stems are a popular raw material used in small-scale papermaking.

The tops of growing nettles are a popular cooked green in many areas, and are exceptionally high in protein. Some cooks throw away a first water to get rid of the stinging compounds, while others retain the water and cook the nettles straight. Nettle tops are sold in some farmers' markets and natural food stores. Nettle is believed to be a galactagogue and a clinical trial has shown that the juice is diuretic in patients with congestive heart failure.

Urtication, or flogging with nettles, is the process of deliberately applying stinging nettles to the skin in order to provoke inflammation. An agent thus used is known as a rubefacient (i.e. something that causes redness). This is done as a folk remedy for rheumatism, as it provides temporary relief from pain.

Extracts can be used to treat arthritis; it is also believed to be diuretic and uses treating hay fever are being investigated.

Nettle is used in hair shampoos to control dandruff, and is said to make hair more glossy, which is why some farmers include a handful of nettles with cattle feed.

Nettle root extracts have been extensively studied in human clinical trials as a treatment for symptoms of benign prostatic hyperplasia (BPH). These extracts have been shown to help relieve symptoms compared to placebo both by themselves and when combined with other herbal medicines.

Because it contains 3,4-divanillyltetrahydrofuran, certain extracts of the nettle are used by bodybuilders in an effort to increase free testosterone by occupying sex-hormone binding globulin.

[edit] Safety

Though the fresh leaves can cause painful stings and acute urticaria, these are rarely seriously harmful. Otherwise most species of nettles are extremely safe and some are even eaten as vegetables after being steamed to remove the stingers.

Nettles can be picked painlessly by wearing a standard pair of washing-up gloves.

The traditional remedy for nettle stings is rubbing with the crushed leaf of the dock plant, Rumex obtusifolius, which often grows beside nettles in the wild and has a milky substance which can cause dermatitus. Plantain is another traditional remedy. The alkalinity of the sap may counteract the nettle's acids. Nettle itself will release alkaline sap when macerated^[1] While there is no scientific proof that this remedy works, searching for and using a dock leaf at least takes the mind off the stinging pain somewhat.

[edit] Popular culture

The Bottle Inn, a pub in Marshwood, Dorset, England, holds an annual World Stinging Nettle Eating Championship.

The 10th World Nettle Eating Championships, held at The Bottle Inn, Marshwood. Saw Jo Carter Landlady of the Boot Inn, Weymouth eat the leaves from a staggering 34 feet of raw stinging nettles to keep the title she jointly held last year and smash the ladies world record (Previous record 24 feet) Jo, a 34 year old school teacher runs the Boot Inn with her partner Giles, she danced a jig of triumph when handed the ladies trophy she also received a case of stinger ale kindly Donated by celebrity chef Hugh Fearnley-Whittingstall.

Jo beat off a truly valiant attempt from first time entrant Sally Payne who consumed the leaves from an amazing 30 feet of nettles, which in any other year would have taken the ladies title. Sally has vowed to return next year, watch out Jo!!!

The Men’s title, after a hotly contested battle, was taken by 41 year old Plant operator, Samuel Ellis, from Northern Ireland but now living in West Coker Somerset. Samuel consumed the leaves from 52 feet of leaves during the hour long duration of the competition, reversing last years result, and beating the out-going champion Ed Brooks by 4 feet.

[edit] See also

• Lamium, the "deadnettles".
• Nettles (folklore)

[edit] Similiar plants

There are further plants, showing similiar effects [1]:

• Dumb cane ( Dieffenbachia spp. )
• Cowhage ( Mucuna pruriens )
• Bull Nettle ( Cnidoscolus stimulosus )
• Ciega-vista ( Croton ciliato-glandulosus )
• Stinging Spurge (Jatropha urens L.)
• Noseburn ( Tragia spp. )
• Giant stinging tree ( Dendrocnide excelsa )
• Gympie ( Dendrocnide moroides )
• Nilgiri Nettle ( Girardinia leschenaultiana )
• Wood Nettle ( Laportea canadensis )
• Tree Nettle ( Laportea spp. )
• Nettle Tree ( Urera baccifera )

[edit] External links and references

• Flora Europaea: Urtica
• Flora of North America: Urtica
• Flora of China: Urtica
• Plants for a Future database search for Nettle
• HerbalGram and American Botanical Council website search for Urtica
• Historical & Current Uses for Nettles

[edit] References

• Chrubasik S, Enderlein W, Bauer R, Grabner W. (1997). Evidence for the antirheumatic effectiveness of herba Urticae dioicae in acute arthritis: A pilot study. Phytomedicine 4: 105-108.
• Dathe G, Schmid H. (1987). Phytotherapy for benign prostatic hyperplasia (BPH): Double-blind study with extract of root of urtica (ERU). Urologe B 27: 223-226 [in German].
• Fu H Y, Chen S J, Chen R F, Ding W H, Kuo-Huang L L, Huang R N (2006). Identification of oxalic acid and tartaric acid as major persistent pain-inducing toxins in the stinging hairs of the nettle, Urtica thunbergiana. Annals of Botany (London), 98:57-65. Abstract
• Holden, Margaret (1948). An alkali-producing mechanism in macerated leaves. Biochemical Journal 42 (3): 332–336. Retrieved on September 25, 2006.
• Kirchhoff HW. (1983). Brennesselsaft als Diuretikum. Z. Phytother. 4: 621-626 [in German].
• Krzeski T, Kazón M, Borkowski A, et al. (1993). Combined extracts of Urtica dioica and Pygeum africanum in the treatment of benign prostatic hyperplasia: double-blind comparison of two doses. Clinical Therapy 15 (6): 1011-1020.
• Mittman, P. (1990). Randomized, double-blind study of freeze-dried Urtica dioica in the treatment of allergic rhinitis. Planta Med 56: 44-47.
• Randall C, Randall H, Dobbs F, et al. (2000). Randomized controlled trial of nettle sting for treatment of base-of-thumb pain. J. Roy. Soc. Med. 93: 305-309. reported online in British Medical Journal
• Yarnell E. (1998). Stinging nettle: A modern view of an ancient healing plant. Alt. Compl. Therapy 4: 180-186 (review).