Poison Hemlock

Poison Hemlock

Conium maculatum L.


Devil's Beard, Devil's Porridge, Hemlock, Poison Parsley, Spotted Corobane, Spotted Hemlock.

ID Characteristics

Life cycle: Biennial or a short-lived perennial
Growth Habit: Tall, erect stalks coming from a basal rosette. All parts of the plant are poisonous.
Propagation: Seed
Leaf Margin: entire
Leaf Hairs: Stems are hairless
Leaf Structure: Bright green fern-like, triangular pinnately compounded leaves divided into deeply lobed leaflets that are lanceolate
Leaf Arrangement: Alternate lower leaflets on stalks with purple streaks, upper leaves nearly stalkless. Plant parts contain alkaloids that are toxic to humans and animals.
Root Type: Taproot
Flower Color: Umbrella-shaped small white on a stalk


Similar Species

  • Caraway, Water Carum carvi
  • Hemlock, Water Cicuta douglasii
  • Queen Ann's Lace or Wild Carrot Daucus carota

Herbicidal Control Options

  • Preemergence: Selective control option not available
  • Post Emergence: Imazapic, 2,4-D, Dicamba, MCPP, Triclopyr, Clopyralid

Please note: one or more of these active ingredients may exist in combination-type brand name products. Any material used for herbicidal control of any plant may vary in efficacy. Please read the full disclaimer on herbicide usage.