Spotted golden thistle (Scolymus maculatus)
Spotted golden thistle is a spiny, upright, branched herb with yellow flowerheads. It forms dense infestations in pastures, reducing productivity and contaminating wool.
Profile
How does this weed affect you?
Spotted golden thistle:
- forms thick clumps that restrict movement of people and animals
- outcompetes pasture plants, reducing productivity
- contaminates and devalues wool
- can harbour pest animals such as rabbits.
What does it look like?
Spotted golden thistle is a spiny, annual herb up to 1 m tall.
Leaves:
Leaves in the rosette at the base of the plants are
- shiny green with white veins and spots
- white along the edges
- 4-20 cm long and 2-8 cm wide
- soft
- deeply divided into many lobes with spines at the tips
Leaves along the stems are:
- smaller
- rigid
- similar in colour
- alternate along the stems
- broad at the base and form wings on the stem.
Flowerheads are:
- golden yellow
- up to 2.5 cm in diameter
- on short stalks
- solitary or in clusters of up to 4 flowers
- surrounded by stiff spiny bracts.
Seeds are:
- yellow brown
- up to 4 mm long
- oval shaped.
Stems:
- are erect
- are slightly hairy
- have spiny wings with thick white edges.
Roots are:
- a fleshy, dark coloured tap root with fibrous roots
- up to 60 cm long and up to 10 cm in diameter.
Where is it found?
In NSW, spotted golden thistle mostly grows in the North West and Hunter regions.
It is native to the Mediterranean region.
Spotted golden thistle grows in warm temperate climates with winter dominant rainfall.
References
Auld B.A. and Medd R.W. (1999). Weeds. An illustrated botanical guide to the weeds of Australia. (Inkata Press, Melbourne).
Parsons, W.T., & Cuthbertson, E. G. (2001). Noxious weeds of Australia. 2nd edition. CSIRO publishing.
PlantNET (The NSW Plant Information Network System). Royal Botanic Gardens and Domain Trust, Sydney. Retrieved 25 September 2026 from: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Scolymus~maculatus
More information
Control
Wear personal protective clothing and equipment when handling this plant to prevent injuries from the spines
Physical removal
Dig out individual plants in small infestations. This is best done before flowering. Remove as much of the roots as possible.
Cultivation
Large infestations can be managed by cultivation before flowering. This needs to be thorough and repeated to kill new seedlings.
Herbicide control
Spraying
Spray while the plants are still in the rosette stage before the stem develops.
Wiping
Apply the herbicide gel to at least 50% of the rosette leaves by wiping the applicator along the middle of each leaf.
Wear personal protective clothing and equipment when handling this plant to prevent injuries from the spines
Physical removal
Dig out individual plants in small infestations. This is best done before flowering. Remove as much of the roots as possible.
Cultivation
Large infestations can be managed by cultivation before flowering. This needs to be thorough and repeated to kill new seedlings.
Herbicide control
Spraying
Spray while the plants are still in the rosette stage before the stem develops.
Wiping
Apply the herbicide gel to at least 50% of the rosette leaves by wiping the applicator along the middle of each leaf.
Herbicide options
Users of agricultural or veterinary chemical products must always read the label and any permit, before using the product, and strictly comply with the directions on the label and the conditions of any permit. Users are not absolved from compliance with the directions on the label or the conditions of the permit by reason of any statement made or not made in this information. To view permits or product labels go to the Australian Pesticides and Veterinary Medicines Authority website www.apvma.gov.au
See Using herbicides for more information.
2,4-D 300 g/L + Picloram 75 g/L
(Tordon® 75-D)
Rate: 300 mL in 100 L of water
Comments: Spot spray.
Withholding period: Do not graze or cut crops (except sugar cane 8 weeks) or pastures for stock food for 7 days after application.
Sugar Cane: Do not harvest for 8 weeks after application. Do not graze or cut for stock food for 8 weeks after application.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
2,4-D 300 g/L + Picloram 75 g/L
(Tordon® 75-D)
Rate: 3.5 L/ha
Comments: Boom spray. Apply to seedling and rosette stages.
Withholding period: Do not graze or cut crops (except sugar cane 8 weeks) or pastures for stock food for 7 days after application.
Sugar Cane: Do not harvest for 8 weeks after application. Do not graze or cut for stock food for 8 weeks after application.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
Dicamba 750 g/L
(Kamba® 750)
Rate: 53 mL in 100 L of water. Add a surfactant.
Comments: Spray prior to flowering. For non crop situations.
Withholding period: Do not harvest, graze or cut for stock food for 7 days after application.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
Fluroxypyr 140 g/L + Aminopyralid 10 g/L
(Various products)
Rate: 500 mL in 100 L of water
Comments: Hand gun application
Withholding period: Not required for pastures when used as directed. Do not graze or cut crops for stock food for 7 days after application. See label for export restrictions.
Herbicide group: 4 (previously group I), Disruptors of plant cell growth (Auxin mimics)
Resistance risk: Moderate
Biosecurity duty
The content provided here is for information purposes only and is taken from the NSW Biosecurity Act 2015 and its subordinate legislation, and the Regional Strategic Weed Management Plans (published by each Local Land Services region in NSW). It describes the state and regional priorities for weeds in New South Wales, Australia.
| Area | Duty |
|---|---|
| All of NSW | General Biosecurity Duty All pest plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant, who knows (or ought to know) of any biosecurity risk, has a duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable. |
Reviewed 2021
