Poison Hemlock—“I know that I know nothing.”

By Steven Foster |

Drive along any field-flanked highway in Northwest Arkansas for the next two weeks, and notice the wall of vegetation created by a tall, gangly plant of no particular beauty. Festooned in tiny-white flowers on flat-topped clusters, this annual weed stretches from six to ten feet tall. The stems are smooth and purple-spotted or -streaked, particularly at the stem base, holding fern-like leaves. Crushed leaves smell as if they ought to be poisonous. This is poison hemlock Conium maculatum, a carrot family member (Umbelliferae). If mistaken for wild carrot (Daucus carota), the results can be fatal. Take note: wild carrot has hairy stems; poison hemlock has smooth stems. Both are European weeds.

All plant parts contain highly variable amounts of toxic alkaloids, especially coniine, which is slowly lost from the plant upon drying. Death from poison hemlock is variously described as tranquil to violently delirious.

The name Conium derives from the Greek konos or “cone top” referring to the hats worn by Sufi whirling dervishes, describing the plant’s effects. Soon after ingesting the green plant’s juice, dizziness with a spinning sensation foretells impending death. Ingested purposefully or by accident, the victim will not be able to stand-up or sit. One must lie down. If dosed appropriately, the victim has about 30 minutes before lungs and heart cease to function, remaining alert and conscious ‘til the end.

Poison Hemlock, Conium maculatumIn ancient Athens, poison hemlock, given in sufficient quantities, caused certain and almost immediate death (within an hour). It was the mode of execution by the tribunal of Areopagus, famously administered to the philosopher Socrates, 470-399 B.C.E. whose crime of not believing in the city’s gods and expressing that to others, earned him a death sentence. Before Oklahoma executioners (that would be the judiciary, legislature and governor acting in secret proceedings) get too excited about the potential of poison hemlock, they should be aware that the historical acceptance of Conium maculatum as the actual poison that killed Socrates only dates to the mid-1750s. Earlier writers suggested that it may have be another poisonous plant or a mixture of several poisonous plants. All deaths ascribed to poison hemlock have not been as peaceful as Plato’s description of Socrates’s serene death. “I know that I know nothing,” said Socrates.

How about you elected official executioners?

More images of Poison Hemlock, Conium maculatum here.

Adapted from Nature of Eureka Column by Steven Foster in the 28 May Issue of the Eureka Springs Independent Newspaper.