Water hemlock
Water hemlock is a common name for highly poisonous flowering plants in the genus Cicuta, in the parsley family Apiaceae.
Water hemlock is a common name for highly poisonous flowering plants in the genus Cicuta, family Apiaceae, that grow in wet habitats across temperate North America. The plants contain cicutoxin, a potent neurotoxin that can cause rapid neurological symptoms and death if ingested. In Canada, water hemlock is native and poses a serious risk when mistaken for edible plants.
Description
Water hemlock is a perennial herbaceous plant with small white flowers arranged in umbrella-shaped clusters, typical of the Apiaceae family. It is commonly described as a wetland plant with very high toxicity.
Toxicity
The plant contains cicutoxin, a powerful poison that affects the central nervous system. Symptoms can appear quickly and may include nausea, abdominal pain, vomiting, seizures, delirium, convulsions, and death. All parts of the plant are toxic, with roots reported as especially poisonous.
Habitat and distribution
Water hemlock grows in wet and marshy places such as stream banks, ditches, swamps, and low meadows. It is native to parts of North America and is widespread in temperate regions.
Identification and confusion with other plants
Water hemlock can be mistaken for other plants in the carrot family, including harmless edible species. Because of this, sources recommend avoiding consumption of any uncertain white-flowered aquatic or wetland plant.
Key facts
- Water hemlock refers to several highly poisonous species in the genus Cicuta.
- All parts of the plant are toxic, with roots especially poisonous.
- The toxin cicutoxin can cause rapid neurological symptoms including seizures and death.
- Water hemlock is often confused with edible members of the carrot family.
- It is considered among the most poisonous plants in North America.
Water hemlock is native in parts of Canada and is relevant to Canadian readers because it grows in wet habitats across temperate North America and has caused serious poisonings where it is mistaken for edible plants.
Frequently asked questions
What is water hemlock?
Why is water hemlock dangerous?
Where does water hemlock grow?
Which parts of the plant are toxic?
Is water hemlock the same as poison hemlock?
References
- Encyclopaedia Britannica — https://www.britannica.com/plant/water-hemlockSupports: Genus-level definition, family, habitat, toxicity, and cicutoxin information.
- U.S. Forest Service — https://www.fs.usda.gov/wildflowers/plant-of-the-week/cicuta_maculata.shtmlSupports: Toxic effects of cicutoxin and the plant's reputation for extreme poisoning.
- USDA Agricultural Research Service — https://www.ars.usda.gov/pacific-west-area/logan-ut/poisonous-plant-research/docs/water-hemlock-cicuta-douglasii/Supports: Assessment of water hemlock as one of the most violently toxic plants in North America.
- University of Florida IFAS — https://www.ifas.ufl.edu/plant-directory/cicuta-maculata/Supports: All parts are poisonous, confusion with edible plants, and wetland habitat.
- Illinois Wildflowers — https://www.illinoiswildflowers.info/wetland/plants/water_hemlock.htmSupports: Roots as especially toxic and species-level identification details.
- Michigan State University Extension — https://www.canr.msu.edu/news/poison-hemlock-identification-and-controlSupports: Native species in North America, wet habitat, and toxin location in roots and other tissues.