How to kill ragwort

Access all the information needed for control of this noxious weed, including weed identification, herbicide application and spray timings.


Ragwort description

Ragwort identification

Ragwort is an upright plant that grows up to 1 m tall. Each plant has numerous separate stems and each rigid branched stem is greenish-purple in colour. The leaves are deeply lobed, ragged in appearance, dark green on top and lighter underneath.

Ragwort flowers are daisy-like, about 1 cm across with bright yellow petals. The seeds are light brown, about 2 mm long by 0.5 mm in diameter and attached to a pappus of feathery hairs.

Mature plants have a crown just beneath the soil surface, from which numerous fleshy roots are produced. Ragwort is poisonous to grazing animals, with cattle, horses and pigs the most susceptible. Cross-bred sheep will eat ragwort without showing ill effects unless continually exposed to the plant in large quantities. Ragwort competes strongly with other plant species and will reduce pasture productivity.

Ragwort control

How to kill ragwort

Prompt action is essential to eradicate known infestations of ragwort and to prevent the spread of the weed to new areas. Management of ragwort infestations requires thorough control measures. Integrated management programs must be well planned if they are to be successful.

Ragwort that is slashed, pulled, cut or broken close to the soil surface will produce new growth from the cut crown or small pieces of root left behind in the soil. Slashing must be followed up with chemical application and/or cultivation and pasture improvement.

Sound pasture management is essential. Maintenance of a dense pasture will reduce seedling establishment. Ragwort seedlings that appear after cultivation should be spot sprayed as a priority.

1. Treating isolated patches and limited infestations

Clean areas should be kept free of ragwort and managed to prevent infestation. Lightly infested areas are best cleaned up as soon as possible to prevent spread. Grazon Extra as a foliar application and Tordon Granules as a hand-applied application are two effective methods.

2. Treating extensive infestations

Extensive infestations are best quarantined and tackled progressively as part of a pasture improvement program, in conjunction with other control techniques. Ragwort control in inaccessible areas may be best achieved by fencing off the area and allowing it to return to bush or by grazing with sheep or goats.

Herbicides for killing ragwort

Product#Method of applicationRate*State
Lontrel® Advanced Herbicide Boom application 500 mL to 1 L/ha + surfactant All
Grazon® Extra Herbicide Controlled droplet application Apply undiluted All
Grazon® Extra Herbicide Foliar spray 350 or 500 mL/100 L of water All
Lontrel® Advanced Herbicide Foliar spray 100-150 mL/100 L of water All

# Note: Preferred product option in bold.  * Consult label for details of growth stage and use, especially where range of rates is given.

Treatment timing

Timing to kill ragwort

Ragwort is normally a biennial but cutting or grazing may delay flowering until a later season.

In practice, the plant becomes a perennial when control measures are attempted. Ragwort reproduces from seed, from root fragments and from the crown of the plant, which persists from season to season.

Ragwort flowers from October to March. Each plant produces numerous seeds. Most seeds germinate almost immediately but some may remain viable in the soil for many years

Grazon® Extra Herbicide
Key: Best time to spray/treat Can spray/treat if conditions are suitable Do not spray/treat