Poison Hemlock

Additional Common Names: Poison Parsley, Spotted Hemlock, Winter Fern, California Fern, Nebraska Fern, Deadly Hemlock
Scientific Name: Conium maculatum
Family: Umbelliferae
Toxicity: Toxic to Dogs, Toxic to Cats, Toxic to Horses
Toxic Principles: Various alkaloids
Clinical Signs: Infrequently causing poisonings, this plant is not likely to be consumed unless other forage is not available. A number of toxic alkaloids are contained within the plant, and the content varies depending on the stage of maturity or repoduction, and climactic conditions. As the plant dries out, the toxic potential disappears. Clinical signs can develop within minutes after ingestion, and may include central nervous system excitation, muscle tremors, incoordination, excessive salivation, frequent bowel movements and urination, abdominal pain, and increased respiratory rate. As the syndrome advances, weakness progresses to muscular paralysis. Death is possible due to respiratory paralysis.

Credit: William & Wilma Follette @ USDA-NRCS PLANTS Database / USDA NRCS. 1992.
Western wetland flora: Field office guide to plant species. West Region, Sacramento, CA.

If your pet ingested this plant, contact your local veterinarian or the ASPCA Animal Poison Control Center at 888-426-4435.*

* A $65 consultation fee may apply.

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