Poison hemlock (Conium maculatum)

Poison Hemlock

(Conium maculatum)


  • Native to Europe and Asia
  • Grows up to 3m tall with musty smelling fern-like leaves
  • Large clusters of five-petalled white flowers that can produce 40,000 seeds per plant. These seeds are viable for up to 6 years.
  • Mature plants have thick, hollow, hairless stems with purple spots and streaks.
  • Grows in a variety of conditions, but prefers moist soil with sun.

Consequences of Invasion

  • WARNING! All parts of the plant are DEADLY to people, livestock, and wildlife when ingested. Young plants can be mistaken for carrots.

Integrated Pest Management Options

  • Mechanical: For small patches, roots may be dug up. Wear protective equipment and wash hands thoroughly after treatment. All landfills within the RDCK and RDKB accept invasive plant species for free. Ensure your material is bagged in clear plastic bags and notify the attendant that you have invasive plant species. Plants must be identifiable through the bag. For more information please see the RDCK Resource Recovery Bylaw.
  • Mechanical: Poison hemlock should not be mowed, as mowing can disperse inhalable toxins into the air.
  • Chemical: Herbicides are available. More information here.
  • Biological: None to date.

Reporting Sightings

If you see this plant, please report it using the provincial reporting tools or send an email to info@ckiss.ca. Please include the following details: date observed, precise location, photos, and the size of the infestation.

Additional Resources:

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