Ontario Wildflowers website

Poison Hemlock
Conium maculatum

Other common names: Snakeweed

French names: Ciguë maculée

Family: Parsley Family (Apiaceae)

Distinctive features: Spotted stem.

Similar species:
  •   Japanese Hedge Parsley (Torilis japonica) - A much more delicate plant.

  •   Spreading Hedge Parsley (Torilis arvensis) - A much more delicate plant.

  •   Water Hemlock (Cicuta maculata) - Grows in wet areas; leaves are not finely divided.

  •   Bulb-bearing Water Hemlock (Cicuta bulbifera) - Grows in wet areas; leaves are very narrow.
  •   Eastern Hemlock (Tsuga canadensis) - A tree; similar in name only; no relation; not poisonous. See the Ontario Trees & Shrubs website.

Flowers: Summer;  White;  5 parts (petals)

Leaves: Alternate, Compound, Toothed

Stem: Spotted stem.

Habitat: Fields and Open Areas

Poisonous: ***DEADLY POISONOUS***.

Books: Newcomb's Wildflower Guide: 220   

Native/Non-native: Non-native

Origin and Meaning of Names:
 Scientific Name: maculatum: spotted


Photographs: 45 photographs available, of which 5 are featured on this page. SCROLL DOWN FOR PHOTOGRAPHS.

Range Map is at the bottom of the page

Poison Hemlock (Conium maculatum)
Photograph by Glenda Theresa Lucas

A view of the overall plant.

Poison Hemlock (Conium maculatum)
Photograph by Glenda Theresa Lucas

The flower umbel.

Poison Hemlock (Conium maculatum)
Photograph by Glenda Theresa Lucas

Poison Hemlock (Conium maculatum)
Photograph by Glenda Theresa Lucas

Closeup showing the spotted stem.

Poison Hemlock (Conium maculatum)
Photograph by Glenda Theresa Lucas

Some leaves. They are finely divided, feather-like.


Range map for Poison Hemlock (Conium maculatum)

PLEASE NOTE: A coloured Province or State means this species occurs somewhere in that Province/State.
The entire Province/State is coloured, regardless of where in that Province/State it occurs.

(Range map provided courtesy of the USDA website and is displayed here in accordance with their Policies)