The plant, Senecio jacobaea is commonly found in the northwestern United States and has been reported to contain 6 pyrrolizidine alkaloids. Pyrrolizidine alkaloids are well known to cause liver damage to humans and livestock. This article reports that 6 pyrrolizidine alkaloids may be rapidly isolated using high-pressure liquid chromatography (HPLC). HPLC also provides evidence that there are a number of other pyrrolizidine alkaloids present in S. jacobaea. Not all these peaks have as yet been identified and characterized. © 1978.