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Created 1999.

Common name: Cushag, Tansy Ragwort, St. James-wort, Ragweed, Stinking Nanny/Ninny/Willy, Staggerwort, Dog Standard, Cankerwort, Stammerwort and Mare's Fart
Botanical name: Senecio jacobaea
Family: Asteraceae
Origin: The Ragwort is native to Europe, from Scandinavia to the Mediterranean. Ragwort can be found along roadsides and waste grounds, and grows in all cool and high rainfall areas. It has been introduced to USA, South America (Argentina), North Africa and to the Asian continent (India and Siberia). It is a widespread weed in New Zealand and Australia. In many Australian states ragwort has been declared a noxious weed.
Description: The plant is biannual or perennial. The stems are erect, straight, with no or few hairs, and reach a height of 0.3-2.0 metres. The common names of Ragwort (Stinking nanny, Mare's Fart, etc) arise because of the unpleasant smell of the leaves. The flower are 1.5-2.5 cm in diameter, and are generally bright yellow.
Uses: A green dye can be obtained from the leaves and a yellow dye from the flowers. During medieval times, Ragwort was used for inflammation of the eye, in the treatment of sore and cancerous ulcers, rheumatism, sciatica, gout, and for painful joints.
Allergens: Sesqueterpene lactones.
Allergy: Ragwort contains many different alkaloids, making it poisonous to animals. In theory it is also toxic to humans but the dose required would be enormous. Contact dermatitis has been reported in those handling the plant.
Cross reactions: Other compositae/asteracea
Other information: The Cinnabar moth Tyria jacobaeae is used as a control for ragwort in some countries, like New Zealand and the western United States. In New Zealand, the ragwort flea beetle (Longitarsus jacobaea) has also been introduced to combat the plant. Ragwort is the national flower of the Isle of Man, where it is known as Cushag.
Patch test: Sesqueterpene lactone mix



  • Botanical Dermatology Database.
  • Harrison K. Ragwort poisoning. Vet Rec. 1999 Aug 21;145(8):236.
  • Mikhnev AL, Lazidi GKh. [Arpephyllin treatment of patients with bronchial asthma] Vrach Delo. 1968 May;5:42-7. Russian.
  • Mitchell JC, Rook A, 1979, Botanical Dermatology, Plants and Plant products injurious to the skin, Greengrass, Vancouver.
  • Young SH, Zimmerman RE, Smithwick EM. The in vitro response of human lymphocytes challenged by ragweed antigen. Pediatrics. 1968 Dec;42(6):976-9.


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