Aethusa cynapium

The Fool's Parsley (Aethusa cynapium) or Fool's Cicely is an annual (rarely biennial) herb in the plant family Apiaceae, native to Europe, western Asia and northwest Africa. It is the only member of the genus Aesthusa.It has a fusiform root and a smooth hollow branched stem growing to about 80 cm high, with much divided (ternately pinnate) smooth leaves with an unpleasant smell, and small compound umbels of small irregular white flowers. It is related to Hemlock and Water-dropwort and like them is poisonous, though the toxins are destroyed by drying, and hay containing the plant is not poisonous. Symptoms of poisoning are heat in the mouth and throat.
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Noun
1. European weed naturalized in America that resembles parsley but causes nausea and poisoning when eaten
(synonym) fool's parsley, lesser hemlock
(hypernym) poisonous plant
(member-holonym) Aethusa, genus Aethusa