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Veratrum nigrum

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Veratrum nigrum (common name black false hellebore)<ref name="Bonine">Bonine, Black Plants: 75 Striking Choices for the Garden, 2009, p. 75.</ref><ref name="Toogood">Toogood, The Gardener's Encyclopedia of Perennials, 1988, p. 144.</ref> is a widespread Eurasian species of perennial flower of the family Melanthiaceae.<ref name=p>Kew World Checklist of Selected Plant Families</ref><ref name="Barecloux815">Barceloux, Medical Toxicology of Natural Substances, 2008, p. 815.</ref> Despite its common name, V. nigrum is not closely related to the true hellebores, nor does it resemble them.

The plant was widely known even in ancient times. For example, Lucretius (ca. 99 BCE – ca. 55 BCE) and Pliny the Elder (23 AD – August 25, 79) both knew of its medicinal emetic as well as deadly toxic properties.<ref>Lucretius Of the Nature of Things, Thomas Creech, ed., 1714, p. 363.</ref>

Distribution and habitat

Veratrum nigrum is native to Eurasia from France to Korea including Germany, Poland, Russia, China, and Mongolia.<ref name=p/><ref>Altervista Flora Italiana, Veratro nero, Veratrum nigrum L. includes photos and European distribution map</ref><ref name="Toogood" /><ref name="Armitrage">Armitage, Armitage's Garden Perennials: A Color Encyclopedia, 2000, p. 269.</ref> The plant can exist in hardiness zones 4 through 7.<ref name="Armitrage" /> It grows best in shade or partial shade, with wet or moist grounds conditions.<ref name="Bonine" /><ref name="Armitrage" /><ref name="Raven">Raven, The Bold and Brilliant Garden, 1999, p. 59.</ref><ref name="Hobhouse">Hobhouse, Flower Gardens, 2001, p. 206.</ref> Any nutrient-rich soil supports its growth,<ref name="Hobhouse" /><ref name="Nicholson">Nicholson, Garrett, and Trail, The Illustrated Dictionary of Gardening, 1887, p. 143.</ref><ref name="Thomas">Thomas, "The Complete Gardener, 1916, p. 72.</ref><ref name="VanDijk" /> although one source observes that it prefers calcium-rich soil.<ref>Hulme, Familiar Swiss Flowers, Figured and Described, 1908, p. 207.</ref> Another source observes that the bed must be fairly deep.<ref name="VanDijk" />

Description

The plant has a robust black rhizome.<ref name="Armitrage" /><ref name="Nicholson" /> Simple angiosperm leaves arranged in a whorled pattern emerge from the base of the plant.<ref name="Armitrage" /> Each whorl is decussate (rotated by half the angle between the leaves in the whorl below), with only two or three whorls around the base.<ref name="Barecloux815" /><ref name="Nicholson" /> Each leaf is sessile (attaching directly to the plant), and about Template:Convert in length.<ref name="Toogood" /><ref>Beckett, The Concise Encyclopedia of Garden Plants, 1983, p. 418.</ref> The leaves are broad, glabrous (smooth), lanceolate in shape, with entire (smooth) edges.<ref name="Nicholson" /> The veins in the leaves branch immediately from the base and run parallel through the leaf, leaving a pleated look.<ref name="Raven" /><ref name="Hobhouse" /><ref name="VanDijk">Van Dijk, Encyclopedia of Border Plants, 1999, p. 304.</ref> Long, green, coarse, woody spike racemes branch off in decussate patterns from the main trunk, with short pedicels supporting a single flower.<ref name="Barecloux815" /><ref name="Nicholson" /> The flowers are purple-black, giving the plant its name.<ref name="Armitrage" /><ref name="Raven" />

Veratrum nigrum blooms in early summer for several weeks,<ref name="Bonine" /><ref name="Raven" /> but goes dormant in intense summer heat.<ref name="Armitrage" /> It tends to grow in colonies,<ref name="Bonine" /> and attains a height of about Template:Convert.<ref name="Toogood" /><ref name="Barecloux815" /><ref name="Armitrage" /> Its racemes branch out to about Template:Convert in width.<ref name="Hobhouse" /> The seed heads are crimson in color.<ref name="Raven" /> Plants grown from seeds will generally push through the earth and sprout leaves in early spring.<ref name="Hobhouse" />


Garden use

Foliage

Veratrum nigrum was used as an ornamental plant in European gardens at least as far back as 1773.<ref>Abercrombie and Mawe, Every Man His Own Gardener, 1773, p. 594.</ref> It was in common use in 1828,<ref>Curtis, General Indexes to the Plants Contained in the First Fifty-Three Volumes of the Botanical Magazine, 1828, p. 711.</ref> and Charles Darwin grew it in his garden in the 1840s.<ref>Darwin, The Correspondence of Charles Darwin, 1985, p. 299.</ref> The plant is still widely used in gardens in Europe and Asia because of its striking black flowers.<ref name="Bonine" /><ref name="Raven" /> It is also used to add height to a garden,<ref name="Raven" /><ref name="Kingsbury" /> and as a means of providing a darker backdrop to more brightly colored plants and flowers.<ref>Martin, Creating Contrast With Dark Plants, 2000, p. 130-131.</ref> The large seed pods weather winter well (tending not to drop in high wind), and it can be a striking winter ornamental seedpod plant as well.<ref name="Kingsbury">Kingsbury, Seedheads in the Garden, 2006, p. 140.</ref> However, it is difficult to find and very expensive in the United States.<ref name="Armitrage" /><ref name="VanDijk" />

This plant has gained the Royal Horticultural Society's Award of Garden Merit.<ref>Template:Cite web</ref>

Propagation is by seed or by division.<ref name="Nicholson" /><ref name="Thomas" /> However, a plant generally takes seven years to reach maturity and flower.<ref name="VanDijk" /> Snails and slugs feed on the plant's rhizomes and leaves, so gardeners must take care to keep these pests away.<ref name="Bonine" /><ref name="Hobhouse" /><ref name="VanDijk" />

Toxicity

All parts of the plant are highly toxic.<ref name="Barecloux816">Barceloux, Medical Toxicology of Natural Substances, 2008, p. 816.</ref> However, the highest concentrations of toxins tend to be in the rhizome.<ref name="Barecloux816" /> Toxicity varies widely depending on the method of preparation (extract, water extract, etc.), and the method of application.<ref name="Barecloux816" /> Just Template:Convert per Template:Convert can cause death due to cardiac arrhythmia.<ref name="Huang247">Huang, The Pharmacology of Chinese Herbs, 1998, p. 247.</ref> Death has even occurred at a dosage as low as Template:Convert.<ref name="Bensky461">Bensky, Clavey, and Stöger, Chinese Herbal Medicine: Materia Medica, 2004, p. 461.</ref>

Veratrum nigrum contains more than 200 steroid-derived alkaloids, including isorubijervine, jervine, pseudojervine, rubijervine, tienmuliumine, tienmuliluminine, and verazine.<ref name="Barecloux816" /><ref name="Huang246">Huang, The Pharmacology of Chinese Herbs, 1998, p. 246.</ref> The herb causes irritation of mucous membranes.<ref name="Huang246" /> When ingested, the irritation of the mucosal membranes of the stomach and intestines will cause nausea and vomiting.<ref name="Barecloux816" /><ref name="Huang246" /> If the herb is introduced to the nose, this mucosal irritation will cause sneezing and coughing.<ref name="Barecloux816" /><ref name="Huang246" /> Ingestion can also cause bradycardia (slow heart rate), hyperactivity, and hypotension (low blood pressure).<ref name="Barecloux816" /> In high concentrations, topical contact can cause skin irritation, excessive tears from the eyes, and redness.<ref name="Barecloux817">Barceloux, Medical Toxicology of Natural Substances, 2008, p. 817.</ref>

Classic symptoms of Veratrum nigrum toxicity include blurred vision, confusion, headache, lightheadedness, nausea, stomach pain, excessive sweating, and vomiting.<ref name="Barecloux817" /> In severe cases, heart arrhythmia, muscle cramps, extreme muscle twitching, paresthesia (the feeling of "pins and needles" all over the body), seizures, weakness, and unconsciousness occur.<ref name="Barecloux817" /> Death may follow.

Toxic symptoms generally resolve themselves after 24 to 48 hours.<ref name="Barecloux817" /> Supportive treatment for the symptoms is usually administered.<ref name="Barecloux817" /> Because extreme vomiting occurs, decontamination (e.g., stomach pumping or the ingestion of activated charcoal) is usually not implemented unless ingestion has occurred within one hour.<ref name="Barecloux817" /> Atropine is usually administered to counteract the low heart rate, and sympathomimetic drugs and liquids administered to raise the blood pressure.<ref name="Barecloux817" />

The herb is also a known teratogen.<ref name="Huang247" /> However, no data exists on whether it can cause birth defects in human beings.<ref name="Barecloux817" />

Medicinal usage

The dry root of Veratrum nigrum can lower blood pressure and slow heart rate, possibly by stimulating the vagus nerve, if taken in small doses internally.<ref name="Huang246" /> It has been used to treat hypertension and cardiac failure, and to treat pre-eclampsia during pregnancy.<ref name="Barecloux815" /> It has been found to act as an antibiotic and insecticide.<ref name="Barecloux815" /><ref name="Huang246" /> Cyclopamine (11-deoxojervine) is one of the alkaloids isolated from the plant which interferes with the hedgehog signaling pathway (Hh). Cyclopamine is under investigation as a possible treatment for several cancers (such as basal cell carcinoma and medulloblastoma) and skin disorders (such as psoriasis), which result from excessive Hh activity.<ref>Barceloux, Medical Toxicology of Natural Substances, 2008, p. 815-816.</ref>

The dried rhizomes of Veratrum nigrum have been used in Chinese herbalism. All of the false hellebore species are collectively called "li lu" (藜蘆) in China. Li lu is administered internally as an emetic, and is also used topically to kill parasites (such as tinea and scabies) or to stop itching.<ref name="Huang247" /><ref name="Bensky461" /> It was most widely used to treat vascular disease.<ref name="Barecloux815" /> Some herbalists refuse to prescribe li lu internally, citing the extreme difficulty in preparing a safe and effective dosage.<ref name="Bensky461" />

Other uses

In Asia, an extract of the herb is mixed with water in a 1 percent to 5 percent solution and used in many rural areas to kill fleas, their larvae, and their eggs in toilets.<ref name="Barecloux815" /><ref name="Huang247" />

References

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Bibliography

  • Abercrombie, John and Mawe, Thomas. Every Man His Own Gardener. London: William Griffin, 1773.
  • Armitage, A.M. Armitage's Garden Perennials: A Color Encyclopedia. Portland, Ore.: Timber Press, 2000.
  • Barceloux, Donald G. Medical Toxicology of Natural Substances: Foods, Fungi, Medicinal Herbs, Plants, and Venomous Animals. Hoboken, N.J.: John Wiley & Sons, 2008.
  • Beckett, Kenneth A. The Concise Encyclopedia of Garden Plants. London: Orbis Publishing, 1983.
  • Bensky, Dan; Clavey, Steven; and Stöger, Erich. Chinese Herbal Medicine: Materia Medica. 3d ed. Seattle, Wash.: Eastland Press, 2004.
  • Bonine, Paul. Black Plants: 75 Striking Choices for the Garden. Portland, Ore.: Timber Press, 2009.
  • Carus, Titus Lucretius. Of the Nature of Things. Thomas Creech, ed. London: J. Matthews, 1714.
  • Darwin, Charles. The Correspondence of Charles Darwin. Frederick Burkhardt and Sydney Smith, eds. Cambridge, U.K.: Cambridge University Press, 1985.
  • Curtis, Samuel. General Indexes to the Plants Contained in the First Fifty-Three Volumes of the Botanical Magazine. London: Edward Couchman, 1828.
  • Hobhouse, Penelope. Flower Gardens. London: Frances Lincoln, 2001.
  • Huang, Kee C. The Pharmacology of Chinese Herbs. 2d ed. New York: CRC Press, 1998.
  • Hulme, F. Edward. Familiar Swiss Flowers, Figured and Described. New York: Cassell, 1908.
  • Kingsbury, Noël. Seedheads in the Garden. Portland, Ore.: Timber Press, 2006.
  • Martin, Freya. Creating Contrast With Dark Plants. Lewes, U.K.: Guild of Master Craftsman Publications, 2000.
  • Nicholson, George; Garrett, John; and Trail, J.W.H. The Illustrated Dictionary of Gardening: A Practical and Scientific Encyclopaedia of Horticulture for Gardeners and Botanists. New York: James Penman, 1887.
  • Pelletier, S.W. Alkaloids: Chemical and Biological Perspectives. New York: Wiley, 1983.
  • Raven, Sarah. The Bold and Brilliant Garden. London: Frances Lincoln, 1999.
  • Thomas, H.H. The Complete Gardener. New York: Cassell and Company, 1916.
  • Toogood, Alan R. The Gardener's Encyclopedia of Perennials. New York City: Gallery Books, 1988.
  • Van Dijk, Hanneke. Encyclopedia of Border Plants. New York: Routledge, 1999.

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