Hemlock
Botanical Name
Conium maculatum
Family
Apiaceae (umbellifer)
Also known as
Poison hemlock
Where is it originally from?
Europe, Asia, North Africa
What does it look like?
Tall (<2 m) branching, musty-smelling annual or biennial, growing as a large rosette initially, then forming a tall, upright flower stem (<1 m) in its second year of growth. Smooth, hollow, branching, blue-green stems have conspicuous pink or purple blotches. Finely divided, fern-like leaves are dark green on upper surface and grey-green underneath. Small white flowers (Sep-Jan) appear in umbrella-shaped fans at top of stems, and are followed by dark brown, barrel-shaped seed capsules. Plant dies after flowering.
Are there any similar species?
Wild carrot (Daucus carota) has a hairy leaf stalk. Fennel (Foeniculum vulgare) has yellow flowers and leaves smell of aniseed.
Why is it weedy?
Seeds in soil germinate readily. Very poisonous to stock and to humans.
How does it spread?
Seeds dispersed short distances by wind, and by water, on machinery, clothing or animals, and in gravel or soil. Most seeds emerge as soon as conditions are suitable for germination, although a few may survive in the soil for up to 3 years.
What damage does it do?
Forms large beds of rosettes, crowding out other species
Which habitats is it likely to invade?
Roadsides, riverbeds, forest margins, damp or marshy areas, waste areas.
What can I do to get rid of it?
1. Physically remove the plant by hand pulling or digging.
WARNING - All parts of this plant are poisonous. Ensure gloves are worn if pulling and do not dipsose of pulled plants to areas where stock may eat them.
2. Foliar spray
Apply either glyphosate (360 g/L active ingredient at 100ml/10L knapsack, 1L/100L gun and hose) plus organosilicone penetrant (3ml/L), to cover entire plant. Note: Glyphosate overspray will kill other (desirable) plants.
OR Apply Metsulfuron herbicide (600g/kg active ingredient at 5g/10L knapsack or 20g/100L gun and hose) plus organosilicone penetrant (3ml/L) Note: Metsulfuron overspray will kill other (desirable) broadleaf plants and has residual activity in the soil which aids in killing below ground parts.
OR triclopyr herbicide (600g/L active ingredient at a 6ml/L) plus organosilicone penetrant (3ml/L). Triclopyr is 'grass friendly' but overspray will damage clover and other broadleaf plants.
WARNING Spraying plants will make them more palatable to stock. Ensure stock are not grazed in paddocks where hemlock plants (dead or alive) are present.
CAUTION: When using any herbicide or pesticide, PLEASE READ THE LABEL THOROUGHLY to ensure that all instructions and directions for the purchase, use and storage of the product, are followed and adhered to.
What can I do to stop it coming back?
Replant with native species to prevent re-establishment. Follow up for seedlings.
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