Giant Hogweed

Also known as:
Cow Parsnip, Giant Carrot

General description

Biennial or perennial megaherb < 5 m tall. Taproot is fibrous. Stems are hollow, finely haired and covered in red/purple spots. Leaves are compound, large, < 50 cm across and serrated. Flowers are small, green/white and borne in umbels.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell giant hogweed. As giant hogweed 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 giant hogweed within the Auckland region.
If you see giant hogweed anywhere in the Auckland region, please report it to Auckland Council at

Riparian and forest margins, roadsides, flood plains, drains.

Seeds dispersed by water, gravity and wind. Human-mediated dispersal through movement of contaminated soil and deliberate plantings.

Forms dense infestations, suppressing native vegetation and exposing banks to erosion during periods of seasonal dieback. Can cause photodermatitis in humans, possibly requiring medical treatment.

Site Management

Recommended approaches

Do not attempt to undertake control of this species. Please report to Auckland Council.

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

Similar species

Chilean rhubarb
Gunnera tinctoria

Chilean rhubarb's leaves are less deeply lobed. It forms tiny green flowers on a spike.

RPMP status

National Pest Plant Accord Species
Whole region (Exclusion)
Giant hogweed - Main species image