Jacobaea vulgaris
species of flowering plant in the daisy family Asteraceae
Jacobaea vulgaris, synonym Senecio jacobaea, is a very common wild flower in the family Asteraceae that is native to northern Eurasia, usually in dry, open places, and has also been widely distributed as a weed elsewhere.
Common names include ragwort, common ragwort, stinking willie, tansy ragwort, benweed, cushag, St. James-wort, stinking nanny/ninny/willy, staggerwort, dog standard, cankerwort, stammerwort. In the western United States it is generally known as tansy ragwort, or tansy, though its resemblance to the true tansy is superficial.
In some countries it is an invasive species and regarded as a noxious weed. In the UK, where it is native, it is often unwanted because of its toxic effect for cattle and horses, but it is also valued for its nectar production which feeds insect pollinators and its ecological importance is thus considered significant.
Description
The plant is generally considered to be biennial but it has the tendency to exhibit perennial properties under certain cultural conditions (such as when subjected to repeated grazing or mowing). The stems are erect, straight, have no or few hairs, and reach a height of 0.3–2.0 metres (1 ft 0 in – 6 ft 7 in). The leaves are pinnately lobed and the end lobe is blunt. The many names that include the word "stinking" (and Mare's Fart) arise because of the unpleasant smell of the leaves.
The public source identifies “Jacobaea vulgaris” as species of flowering plant in the daisy family Asteraceae. This brief keeps that definition visible, then builds a research path around Jacobaea, vulgaris and species.
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A short description can identify a subject without explaining its stakes. For “Jacobaea vulgaris”, the useful work is to connect “species of flowering plant in the daisy family Asteraceae” to the records capable of establishing context and consequence.
Stable identifiers, scientific names and standards terminology offer the best bridge between this overview and specialist evidence. The source revision retrieved here is dated Aug 23, 2026. The linked authority identifier is Q15630491.
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This entry incorporates text from “Jacobaea vulgaris” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.