Stinking Mayweed (Anthemis cotula)

Photo: (c) Cornwell University CC BY 2.0 license

Family: Asteraceae

Growth Habit: Stinking Mayweed is an annual winter herb of the daisy family, growing from 20 to 60 cm high. Stinking Mayweed has a strong unpleasant odour when crushed and a bitter taste. The stems are erect and densely branched topped by a single large flower head. The leaves look similar to fennel, pinnate in shape with many extremely thin lobes up to 5 cm long.

Type of Plant: Stinking Mayweed is a small erect annual winter herb.

Photo: (c) Cornwell University CC BY 2.0 license

Flowers: Stinking Mayweed has a daisy-like flower, 2.5 cm in diameter, yellow in the centre which is surrounded by 10-18 white florets.

Fruit/Seed:  Achenes (simple dry fruit), wrinkled, ribbed with ten ridges, and small glandular bumps across the surface. The majority of seeds are produced through spring and summer, although, seed production can occur throughout the year.

Dispersal: Reproduces by seed. The plant germinates mainly in Autumn and Spring but it can germinate any time in the year if there is plenty of moisture.

Distribution: Stinking mayweed is widely distributed in Tasmania, especially in the north and north-west. Smaller populations occur in the south around Hobart. This weed is located on roadsides, cultivated paddocks and waste places.

Status: Secondary in Tasmania.

Weed Impact:

  • Stinking Mayweed contaminates animal products if ingested, although it is seldom eaten due to its pungent nature.
  • May cause poisoning in poultry, dogs, cats, horses and guinea pigs.
  • Possibly causes human dermatitis.

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

Control Methods:

  • Machinery, equipment and vehicles which have been used on infested areas should be thoroughly cleaned on leaving. Ensure that all machinery, equipment and vehicles coming onto your property are not contaminated. Washdown Guidelines for Weed and Disease Control.
  • Grubbing. Isolated plants and small infestations can be removed using hand tools.
  • Pasture management (all year). Maintaining a vigorous pasture and avoiding overgrazing will help control stinking mayweed.
  • Large infestations can be controlled by repeated cultivation and cropping. Sow as late as possible and treat any Stinking Mayweed seedlings in the crop with herbicide. Repeat cultivations as required to kill later germinations.
  • Herbicides (summer). Spot spray for smaller patches and boom spray for larger areas. Herbicides registered in Tasmania include 2,4-D, MCPA and glyphosate. DPIPWE Herbicides for Stinking Mayweed Control

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