Tansy (Tanacetum vulgare) is a perennial, herbaceous flowering plant of the aster family, native to temperate Europe and Asia. It has been introduced to other parts of the world, including North America, and in some areas has become invasive. It is also known as common tansy,<ref>Template:PLANTS</ref> bitter buttons, cow bitter, or golden buttons.
Tansy is a flowering herbaceous plant with finely divided compound leaves and yellow, button-like flowers. It has a stout, somewhat reddish, erect stem, usually smooth, Template:Convert tall, and branching near the top. The leaves are alternate, Template:Convert long and are pinnately lobed, divided almost to the center into about seven pairs of segments, or lobes, which are again divided into smaller lobes having saw-toothed edges, giving the leaf a somewhat fernlike appearance. The roundish, flat-topped, button-like, yellow flower heads are produced in terminal clusters from mid-to-late summer. The scent is similar to that of camphor with hints of rosemary. The leaves and flowers are toxic if consumed in large quantities; the volatile oil contains toxic compounds including thujone, which can cause convulsions and liver and brain damage. Some insects, notably the tansy beetle Chrysolina graminis, have resistance to the toxins and subsist almost exclusively on the plant.
History and distribution
Tansy is native to Eurasia; it is found in almost all parts of mainland Europe, as well as Britain and Ireland. It is absent from Siberia and some of the Mediterranean islands.<ref>Template:Cite journal</ref> The ancient Greeks may have been the first to cultivate it as a medicinal herb.<ref name=lecain>Template:Cite web</ref> In the sixteenth century it was considered to be "necessary for a garden" in Britain.<ref>Template:Cite journal</ref>
History of uses
Tansy has a long history of use. It was first recorded as being cultivated by the ancient Greeks for medicinal purposes. In the 8th century AD it was grown in the herb gardens of Charlemagne and by Benedictine monks of the Swiss monastery of Saint Gall. Tansy was used to treat intestinal worms, rheumatism, digestive problems, fevers, sores, and to bring out measles.<ref name=lecain/><ref name=lestrange>Template:Cite book</ref><ref name=mitich>Template:Cite journal</ref><ref name=zimdahl>Template:Cite book</ref><ref name=durant>Template:Cite book</ref>
During the Middle Ages and later, high doses were used to induce abortions.<ref name=mitich/><ref name=kingsbury>Template:Cite book</ref><ref name=illinois>Template:Cite web</ref> Contradictorily, tansy was also used to help women conceive and to prevent miscarriages.<ref name=lestrange/><ref name=mitich/><ref name=haughton>Template:Cite book</ref> In the 15th century, Christians began serving tansy with Lenten meals to commemorate the bitter herbs eaten by the Israelites.<ref name=durant/><ref name=haughton/> Tansy was thought to have the added Lenten benefits of controlling flatulence brought on by days of eating fish and pulses<ref name=lestrange/><ref name=mitich/> and of preventing the intestinal worms believed to be caused by eating fish during Lent.<ref name=sumner/>
Tansy was used as a face wash and was reported to lighten and purify the skin.<ref name=lestrange/><ref name=mitich/> In the 19th century, Irish folklore suggested that bathing in a solution of tansy and salts would cure joint pain.<ref name=egan/> Although most of its medicinal uses have been discredited, tansy is still a component of some medicines and is listed by the United States Pharmacopeia as a treatment for fevers, feverish colds, and jaundice.<ref name=lecain/><ref name=mitich/><ref name=haughton/>Template:Medical citation needed
Tansy has also been cultivated and used for its insect repellent and in the worm warding type of embalming.<ref name=lecain/><ref name=mitich/><ref name=zimdahl/> It was packed into coffins, wrapped in funeral winding sheets, and tansy wreaths were sometimes placed on the dead.<ref name=lecain/><ref name=mitich/><ref name=zimdahl/><ref name=haughton/> Henry Dunster, the first president of Harvard University, was buried wearing a tansy wreath in a coffin packed with tansy; when “God’s Acre” was moved in 1846 the tansy had maintained its shape and fragrance, helping to identify the president’s remains.<ref name=lecain/><ref name=mitich/><ref name=haughton/> By the 19th century, tansy was used so much at New England funerals that people began to disdain it for its morbid association with death.<ref name=mitich/><ref name=durant/>
During the American colonial period, meat was frequently rubbed with or packed in tansy leaves to repel insects and delay spoilage.<ref name=lecain/><ref name=mitich/><ref name=haughton/> Tansy was frequently worn at that time in shoes to prevent malaria and other fevers;<ref name=mitich/><ref name=haughton/> it has been shown, however, that some mosquito species, including Culex pipiens, take nectar from tansy flowers.<ref>Template:Cite journal</ref>
Tansy can be used as in companion planting and for biological pest control. It is planted alongside potatoes to repel the Colorado potato beetle, with one study finding tansy reduced the beetle population by 60 to 100%.<ref name=mitich/><ref>Template:Cite journal</ref><ref>Template:Cite web</ref>
In England tansy is placed on window sills to repel flies; sprigs are placed in bed linen to drive away pests, and it has been used as an ant repellent.<ref>Template:Cite journal</ref>
In the 1940s, distilled tansy oil mixed with fleabane, pennyroyal and diluted alcohol was a well-known mosquito repellent; collectors were paid five cents a pound for tansy in full bloom.<ref name=mitich/><ref>Template:Cite book</ref> Research has found that tansy extracts do indeed repel mosquitoes, but not as effectively as products containing DEET.<ref name=mitich/><ref name=DePooter89>Template:Cite journal</ref> In 2008, researchers in Sweden investigated the use of tansy to repel ticks, showing a 64–72% repellency for each oil constituent.<ref>Template:Cite journal</ref>
Many tansy species contain a volatile oil which can cause contact dermatitis in sensitive individuals. If taken internally, toxic metabolites are produced as the oil is broken down in the liver and digestive tract. It is highly toxic to internal parasites, and for centuries tansy tea has been prescribed by herbalists to expel worms. Tansy is an effective insecticide and is highly toxic to arthropods.<ref>Edible and Medicinal Plants of the West, Gregory L. Tilford, Template:ISBN</ref> Because it contains thujone, the U.S. FDA limits the use of tansy to alcoholic beverages, and the final product must be thujone-free.<ref>Food Additives Permitted for Direct Addition to Food for Human Consumption. Food and Drug Administration (2007). Retrieved Mar 30, 2008.</ref> Tanacetum annuum is often confused with common tansy (Tanacetum vulgare) but the former produces an essential oil that is completely different chemically as it contains no thujone and high amounts of chamazulene making the oil dark blue in color, giving rise to it common name of Blue Tansy Oil.<ref>J. Essent. Oil Res., Vol. 11, 343-348 (1999)</ref><ref>J. Essent. Oil Res., Vol. 12, 122-124 (Jan/Feb 2000)</ref> Despite claims by some unethical resellers of essential oils who adulterate the very expensive Blue Tansy (Tanacetum annuum) oil with the much cheaper oil from Tanacetum vulgare, it should be noted that the oil from Tanacetum vulgare is never blue in color as it contains no chamazulene.<ref>J. Agric. Food Chem., 2004, 52 (6), pp 1742–1748</ref><ref>J. Nat. Prod., 1984, 47 (6), pp 964–969.</ref> For this reason a high thujone oil from Tanacetum vulgare should never be referred to as "Blue Tansy" oil and any such blue oil containing significant thujone is an adulterated product.
The active components of the volatile oil include 1,8-cineole, trans-thujone, camphor and myrtenol, with the quantities and proportions of each varying seasonally and from plant to plant.<ref name=mitich/><ref name=DePooter89/><ref name=Jacobs08>Template:Cite web</ref><ref name=Judzentiene05>Template:Cite journal</ref><ref>Template:Cite journal</ref>
1,8-Cineole is a toxin believed to defend the plant leaves against attacks by herbivores.<ref name=Jacobs08/><ref name=Judzentiene05/>
Tansy was formerly used as a flavoring for puddings and omelets, but is now almost unknown. The herbalist John Gerard (c. 1545–1612) noted that tansy was well known as “pleasant in taste”, and he recommends tansy sweetmeats as “an especial thing against the gout, if every day for a certain space a reasonable quantitie thereof be eaten fasting.” In Yorkshire, tansy and caraway seeds were traditionally used in biscuits served at funerals.<ref name=sumner/>
During the Restoration, a "tansy" was a sweet omelette flavoured with tansy juice. In the BBC documentary "The Supersizers go ... Restoration", Allegra McEvedy described the flavour as "fruity, sharpness to it and then there's a sort of explosion of cool heat a bit like peppermint."<ref>//www.youtube.com/watch?v=TCfx98Ei5lM and //www.youtube.com/watch?v=fCiBMDhs5p0</ref> However, the programme's presenter Sue Perkins experienced tansy toxicity.
For many years, tansy has been used as a medicinal herb despite its toxicity. 19th-century Irish folklore suggests bathing in a solution of tansy and salt as a cure for joint pain.<ref name="egan">Template:Cite journal</ref> A bitter tea made with tansy flowers has been used for centuries as an anthelmintic to treat parasitic worm infestations, and tansy cakes were traditionally eaten during Lent because it was believed that eating fish during Lent caused intestinal worms.<ref name="sumner">Template:Cite book</ref> Various Tanacetum species are used ethnomedically to treat migraine, neuralgia and rheumatism and as anthelmintics. Traditionally, tansy was often used for its emmenagogue effects to bring on menstruation or end an unwanted pregnancy, and pregnant women are advised to not use this herb.<ref name=arnold>Template:Cite book</ref> Research published in 2011 identified 3,5-dicaffeoylquinic acid (3,5-DCQA) and axillarin in tansy as antiviral compounds that are active against herpes simplex virus.<ref name="Parral">Template:Cite journal</ref>Template:Medical citation needed
Among Native Americans
The Cherokee use an infusion of the plant for backache, use the plant as a tonic, and wear it around the waist and in shoes to prevent miscarriages.<ref>Hamel, Paul B. and Mary U. Chiltoskey 1975 Cherokee Plants and Their Uses -- A 400 Year History. Sylva, N.C. Herald Publishing Co. (p. 58)</ref> The Cheyenne use an infusion of the pulverized leaves and blossoms for dizziness and weakness.<ref>Grinnell, George Bird 1972 The Cheyenne Indians - Their History and Ways of Life Vol.2. Lincoln. University of Nebraska Press (p. 190).</ref>
Some traditional dyers use tansy to produce a golden-yellow color.<ref>Template:Cite web</ref> The yellow flowers are dried for use in floral arrangements.
Tansy is also used as a companion plant, especially with cucurbits like cucumbers and squash, or with roses or various berries. It is thought to repel ants, cucumber beetles, Japanese beetles, squash bugs, and some kinds of flying insects, among others.
Dried tansy is used by some bee-keepers as fuel in a bee smoker.
- Common ragwort (Senecio jacobaea) which in some regions is called "tansy ragwort"
- Silverweed (Potentilla anserina) a flowering plant once known as "wild tansy"
- List of companion plants
- Tansy beetle