Eupatorium cannabinum

Eupatorium cannabinum, commonly known as hemp-agrimony, or holy rope, is a herbaceous plant of the daisy family. It is a robust perennial native to many areas of Europe. It is cultivated as an ornamental and occasionally found as a garden escape in scattered locations in China, the United States and Canada. It is extremely attractive to butterflies, much like buddleia. If the genus Eupatorium is defined in a restricted sense (about 42 species), E. cannabinum is the only species of that genus native to Europe (with the remainder in Asia or North America). Eupatorium cannabinum is a perennial herb up to 1.5 meters (4.9 feet) tall or more and 1.2 meters (3.9 feet) wide. It lives in moist low-lying areas in temperate Eurasia. It is dioecious, with racemes of mauve flower heads which are pollinated by insects from July to early September. The flowers are visited by many types of insects, and can be characterized by a generalized pollination syndrome. The flower heads are tiny, fluffy and can be pale dusty pink or whitish. The fruit is an achene about 2 or 3 mm long, borne by a pappus with hairs 3 to 5 mm long, which is distributed by the wind. The plant over-winters as a hemicryptophyte. Eupatorium cannabinum contains tumorigenic pyrrolizidine alkaloids. The alkaloids may be present in the plant material as their N-oxides. E. cannabinum is used in the European traditional medicine as anti-inflammatory agent for respiratory tract diseases, and several of its sesquiterpene lactone constituents were identified to have anti-inflammatory effect in isolated human neutrophils, with the anti-inflammatory action of the sesquiterpene lactone eupatoriopicrin being verified also in mouse peritonitis model.