06/11/2026
It’s very visible right now.
It's time for everyone's favorite tradition--that one time each year when we quote from Plato’s Phaedo: “Crito, we owe a c**k to Asklepios. Pay it and do not neglect it.”
According to Plato, those were the last words of Socrates after he chose to drink a tea brewed with poison hemlock (Conium maculatum)--the same plant pictured here that has been spreading as an invasive species across the United States.* Originally native to Europe, northern Africa, and western Asia, Conium maculatum was introduced to the United States as an ornamental plant.*
True to its common name, this biennial plant is poisonous. As Doris Behnke writes for University of Maryland Extension, "Poison hemlock is toxic to humans and to livestock if ingested by affecting the respiratory, central nervous, and reproductive systems. Some humans and animals can experience dermatitis on the skin just by coming into direct contact with this w**d due to the potency of the eight alkaloids that contribute to its toxicity. All parts of this plant are poisonous and can be fatal to livestock and humans if ingested."*
Growing as an "erect biennial," Conium maculatum is most readily identified by its "smooth, hollow stems that are covered with purple spots."*
To help you better identify Conium maculatum, check out the Penn State Extension article cited below.
Sources:
* “Poison Hemlock Identification and Management,” Doris Behnke (Principal Agent Associate), University of Maryland Extension (updated Nov. 1, 2024) (https://extension.umd.edu/resource/poison-hemlock-identification-and-management/.
“Poison Hemlock Identification,” Liz Bozak, Ph.D. (Extension Educator), Penn State Extension (accessed June 7, 2026) ( https://extension.psu.edu/poison-hemlock-identification).
