Tanacetum vulgare Compositae

Tansy produces a volatile oil that contains up to 70 per cent thujone, bitter glycosides, pyrethrins, tannin, vitamin C and citric acid.

Traditionally tansy has been used as a strewing herb to deter insects and also for treating parasites. A strong decoction made by steeping 25g (¾oz) each of tansy leaves and poke root in 0.6 litre (1 pint) of boiling water can be used in a compress to bring relief to rheumatic joints, bruises and sprains. Tansy should be used only under the supervision of a medical herbalist, and not in pregnancy.