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Poison Hemlock
Conium maculatum L.
Apiaceae (Carrot Family)
▲ ▼ seedlings
▲▼ Young plants
▲▼ Young plants
▲▼ Young plants
Leaf ▲▼
▲▼Spotted stems
▲▼Spotted stems
▲▼Spotted stems
▲▼ mature, flowering plants
▲▼ mature, flowering plants
▲▼ mature, flowering plants
▲▼ flowers
▲ young plants growing at base of past season's dried flowering stems
Colony of poison hemlock in June along roadside in pasture▲
Conium maculatum
L.; Poison Hemlock:
(Bayer Code:
COIMA; US Code COMA2)
· Herbaceous biennial native to Europe
· Produces large rosette of finely divided, fernlike leaves in fall of first year
· Produces elongated, spotted (usually hairless or nearly so), flower stalk with multiple loose umbels of tiny white flowers
· Flower stalk can grow 3-8 feet tall, sometimes taller
· Appears very similar to Wild Carrot/Queen Ann's Lace:
o Wild Carrot has hairy stems, and leaves and has a carrot-like odor; dried flower heads fold up into funnel shape
o Poison Hemlock is nearly hairless; flowering stems smooth or waxy with purple spots; stems and leaves have a musky (mousy) odor; dried flower head remain open, flat
· Entire plant is poisonous to consume; some people get contact dermatitis from foliage contact
· Consuming very small amount of plant can be deadly to humans—leaves are most poisonous part
· Also causes sickness in grazing livestock
· Very common in southwest Missouri