Acaena agnipila

Sheep's bur

Family: Rosaceae

Origin: Australia

Regional Pest Management Plan (RPMP) status

  • Whole region — Sustained control
  • Hauraki Gulf Controlled Area Notice pest

View more about the RPMP statuses

General description

Erect, clump-forming perennial herb < 80 cm tall. Leaves are divided into pairs of toothed, soft-haired leaflets.

Flowers are spiny, green with purple anthers, and borne on narrow flower spikes. Fruits are covered with red, barbed spines.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell sheep's bur within the Auckland region.
  • You must not plant sheep's bur within the Auckland region, unless you are transferring an existing plant on your land to another location within the boundaries of the same property.
  • You must destroy any sheep's bur on land that you occupy if it has been planted in breach of the above rules and you are directed to do so by an authorised person.

Habitats

Grassland, pasture, riverbeds, roadsides, wastelands, plantations.

Dispersal

Seeds dispersed by attachment to wool, fur and clothing.

Impact on environment

Burs get tangled in and contaminate sheep wool.

Control

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

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

Seeds have spines.

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

Close up on a stalk of sheep's bur.
A perennial herb growing up to 80cm tall. Leaves have little teeth and soft hairs.
Photo credit: Harry Rose
Sheep's bur growing in a cluster.
Flowers are spiny and green and grow on narrow spikes. Seeds form on burs which are prickly, and these catch on clothing and animal pelts and are transported to new areas.
Photo credit: Harry Rose