poison hemlock

Any of several poisonous herbaceous plants of the parsley family, especially , believed to be the plant that killed Socrates. It is now common in the U.S. as well as in Europe. A tall biennial, this plant has green stems spotted with red or purple, large compound leaves, and white flowers. Though the poison is concentrated in the seeds, the entire plant is dangerous to livestock when fresh. Despite their common name, poison hemlocks are not conifers (see hemlock). Water hemlocks ( species) are similar and also dangerous.

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