The pest search is moving to the Tiaki Tāmaki Makaurau website from early June 2021. Find out more.

Variegated Thistle

Also known as:
Milk Thistle
Europe, Mediterranean

General description

Large annual or biennial prickly thistle < 2.5 m tall and < 2 m in diameter. Leaves are variegated, with white veins and blotches. Flowers are purple, surrounded by spines and borne in late spring – summer. Achenes bear pappus and ripen in summer – autumn.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell variegated thistle within the Auckland region.
  • You must not plant variegated thistle within the Auckland region.
  • You must destroy any variegated thistle plants on land that you occupy.

Pasture, croplands, river flats, roadsides.

Seeds dispersed by wind and contaminated soil, machinery and animals.

Competes with valued pasture plants. Can be toxic to livestock.

Site Management

Maintaining good pasture cover can prevent establishment or suppress an infestation. Prevent overgrazing especially in summer. Other herbicides are available for selective use in pasture.

Recommended approaches

Physical control

Method: Dig or grub out at least the first 5cm of taproot

Plant parts requiring disposal: Seeds

Disposal options: Remove to greenwaste or landfill if practical


Biocontrol is currently not available for this species.

Community agrichemical control recommendations

No qualifications
Foliar spray with 100ml glyphosate green per 10L of water

Certified Handler/Experienced agrichemical user
Foliar spray with 100ml glyphosate green per 10L of water and 20ml penetrant

Safety notes

Plant has spines.

CAUTION: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.

RPMP status

Whole region (Sustained Control)
Hauraki Gulf Controlled Area Notice pest
Variegated thistle - Main species image