Whilst both the Latin and English names might tempt those inclined to try smoking the leaves, they would be disappointed. The plant contains no psychoactive compounds, is unrelated to Hemp (Cannabis sativa) but has similar leaves. I was amused to read that the Drug Squad paid a visit to the Sussex Trust for Nature Headquarters following a tip off from a concerned visitor. No butterflies were arrested!
The Genus name Eupatorium traces back to the Greek king Mithridates Eupator (120-63 BC), said to be the first to use species in this genus as medicines. But with laxative, diuretic and purgative effects, definitely not one to eat. Anglo Saxons used it as a poultice for wounds to stop bleeding and prevent infection, whilst the common name ague weed comes from its use to treat fevers. It does contain many compounds with potential anti inflammatory and antiviral effects but the roots and leaves are now known to be rich in liver toxic, carcinogenic pyrrolizidine alkaloids (in plants a defence against herbivores)
The stem and leaves, like hemp are tough and the common name Holy Rope comes from the legend of it being used to bind Christ to the cross.
My favourite local name is Raspberries and Cream which captures the creamy haze from the long white stigmas protruding from the pinky purple flowers. Rich in nectar, our pollinators love it. The patch of hemp agrimony near the bench circle in Frank’s Wood is a great place to butterfly watch in Summer. Looking a bit rain battered at the moment. More on Hemp Agrimony. A lovely blog