A branched, straggling annual or perennial, about a foot or so high, more like a short Marsh Ragwort than Common Ragwort, and virtually hairless, with glossy leaves varying from deeply pinnately lobed to undivided, only the lower ones stalked. Fruits normally all downy. An increasing invader of walls, waysides, railway banks, waste and cultivated ground, though still far from everywhere and very local in the N and Ireland. Toxicity All parts of Ragwort are poisonous. Stems contain from 25 to 50 percent of the alkaloid concentration found in the leaves, whereas the flowers contain at least twice as much as the leaves.
Ragwort contains six different pyrrolizidine alkaloids, which accumulate in the liver.
When these compounds are converted in pyrroles, they cause liver damage. Poisoning often occurs when small plants intermixed with desirable forage are ingested accidentally by cattle and horses while grazing. Animals may die after consuming 3 to 7 percent of their body weight in Ragwort. Ragwort poisoning also is caused by contaminated hay or silage. Stock cannot avoid it in hay or silage, and the poisonous alkaloids are unaffected by drying or ensiling.