Gunnera tinctoria

Chilean rhubarb

Family: Gunneraceae

Origin: South America

Large leaves with a flower in the centre of the Chilean rhubarb.
Chilean rhubarb is a giant, rhubarb-like herb with huge prickly leaves. It can grow to be 2.5 m tall.
Photo credit: C. Howell, Department of Conservation

Regional Pest Management Plan (RPMP) status

  • National Pest Plant Accord Species
  • Whole region — Sustained control

View more about the RPMP statuses

General description

Clump-forming perennial herb < 2.5 m tall. Rhizomes are stout. Leaves are very large and prickly. Flowers are minute, green and borne on dense, closely branched, < 1 m long conical panicles in early summer. Drupes are c. 2 mm long.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell Chilean rhubarb. As Chilean rhubarb is a National Pest Plant Accord species, these restrictions apply within the Auckland region and across the whole of New Zealand.
  • You must not plant Chilean rhubarb within the Auckland region.
  • You must destroy any Chilean rhubarb 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

Coastal and riparian areas, cliffs, wetlands, disturbed sites, slips, roadsides.

Dispersal

Seeds dispersed by water, birds, wind and livestock. Vegetative spread from rhizome fragments.

Impact on environment

Forms dense colonies, displacing and suppressing native vegetation.

Control

Site Management

Follow up treated areas 3 times per year. Encourage natural regeneration of native plants or replant treated areas where possible after 2-3 treatments to establish dense ground cover and minimise reinvasion.

Recommended approaches

Physical control

Method: Dig out.

Plant parts requiring disposal: Seeds and rhizomes.

Disposal options: Remove to greenwaste or landfill if practical.

Biocontrol

Biocontrol is currently not available for this species.

Community agrichemical control recommendations

No qualifications: Cut stump and paste freshly cut base of stems with double strength glyphosate gel
or cut stump and spray freshly cut base with 200ml glyphosate green per 1L of water.

Certified Handler/Experienced agrichemical user: Foliar spray with 200ml 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.

Close up of Chilean rhubarb flower.
The spikes are covered in little flowers that are followed by tiny orange fruits.
Photo credit: C. Howell, Department of Conservation
Chilean rhubarb leaves.
Leaves are rough, wrinkled and umbrella-sized on sturdy stalks.
Photo credit: C. Howell, Department of Conservation
Large Chilean rhubarb leaves.
Forms dense patches that exclude other plants.
Photo credit: Colin Ogle
Chilean rhubarb leaves.
Chilean rhubarb produces large amounts seed.
Photo credit: Jonathan Boow