Every great murder mystery has a key ingredient. To the naked eye, everything looks similar. The murderer is hidden amongst a sea of victims. The novel would lose the reader if the antagonist was obvious to everyone around from the start. The wilds of Wintergreen are home to the deadliest plant in North America. This edition of the Nine Minute Naturalist delves into the details of the native spotted water hemlock that hides in plain sight at Wintergreen.

The Apiaceae family, otherwise known as the parsley or carrot family, is large and diverse. Boasting more than 3700 species of plants, this family has numerous members important as leaf and root vegetables, herbs, spices, and ornamental plants. Carrot, celery, parsnip, parsley, anise, coriander, dill, cumin, and Queen Anne’s lace are just a few of the species that provide the world tremendous benefit. This family has a hefty number of “black sheep” members. Nearly 60 species of cow parsnip, especially giant hogweed, cause skin irritation and while some such as poison hemlock and fool’s parsley are deadly poisonous. The deadliest of them all is spotted water hemlock (Cicuta maculata).

Water hemlock is at home in the freshwater marshes of North America. It has a massive home range but needs to be in those locations which keeps its “feet” wet. This is a perennial herb identified by having leaflets with veins ending in the notch between the teeth. These key features distinguish it from other members of the Apiaceae family. Their first-year growth is in low-growing rosette while they mature in year two and develop a talk stalk up to 8 feet tall. It has umbrella-like clusters of small white flowers which bloom from early summer to early fall. They are pollinated by bees, wasps and butterflies and are a host plant for the black swallowtail butterfly.

What makes this plant truly unique is its poison. The primary toxin is called cicutoxin, which affects the nervous system as an incredibly potent stimulant. Cicutoxin turns off the inhibitory neurotransmitter causing the body to go nuts. Cicutoxin causes everything to start firing leading to sweating, vomiting, salivating, stomach pain, delirium, convulsions, seizures all within the first hour. Kidney failure is common along with irregular heartbeat and difficulty breathing. The result is quite often death within two hours of consuming water hemlock.

Hemlock will always be known as the method of death for Socrates, chosen as opposed to a life of exile. Make no mistake, he did not choose the terrible death of water hemlock. His choose was poison hemlock, a European native that has become abundant across North America. Poison hemlock is quite deadly but the method is quite differently. Poison hemlock uses coniine which is a neurotoxin for humans and causes death via respiratory paralysis. You stop breathing and your heart stops. Not a great method death but certainly less violent than water hemlock. Poison hemlock can be differentiated from water hemlock by its almost fern-like leaf and the stem is spotted with purple. It is also found in a bit drier location than its look alike spotted water hemlock, who insists on having its feet wet.

If you want to see the deadliest plant in North America, spend time in the wetlands of Wintergreen. The Shamokin Springs and Allen Creek Nature Preserve have an abundance of the plant along their waterways. This is a plant that should be seen and not touched! Good luck finding this hidden killer.