Hemlock

Conium maculatum
Family: Apiaceae

Growth Habit: An erect plant which can reach a height of 2.75m but normally averages 1-1.5m. Hemlock has hollow, pale green stems with purplish patches. The plant also has large, pale green leaves, similar to carrot leaves.

Type of Plant: Hemlock can be an annual or biennial.

Flowers: Broad flower heads are produced in summer, which comprise hundreds of tiny white flowers.

Fruit/Seed: Thousands of tiny seeds are produced in autumn.

Dispersal: Reproduces by seed, and from fragments of the root system if disturbed, such as by earthmoving equipment.

Distribution: Hemlock can be usually found on disturbed ground or in damp areas. It is also common on roadsides.

Status: Secondary in Tasmania.

Weed Impact:

  • All parts of the plant are poisonous to both humans and livestock. This is due to the presence of 5 alkaloids, coniceine and coniine being the most active.
  • The plant is toxic either green or dried in hay.
  • Rarely causes significant economic losses to crops.

For further information contact the Department of Primary Industry, Water and Environment, Tasmania.

Control Methods:

  • Grubbing (all year). Isolated plants may be manually removed with a fork or similar tool. Wear gloves as this plant has poisonous properties.
  • Herbicide (spring, summer). Herbicides registered in Tasmania include 2,4-D, triclopyr, MCPA + glyphosate. BE WARNED: As herbicide treated plants are attractive to stock, they must be kept away till plant completely disintegrates.

N.B. Always check the herbicide label before use.