Appearance
"Eupatorium cannabinum" is a perennial herb up to 1.5 meters tall or more and 1.2 meters 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.
Defense
"Eupatorium cannabinum" contains tumorigenic pyrrolizidine alkaloids. The alkaloids may be present in the plant material as their N-oxides.References:
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