Cyathea cooperi

Rough tree fern

Also known as:

Australian tree fern

Family: Cyatheaceae

Origin: Australia

A canopy of rough tree fern leaves.
The tree fern can grow as high as 12m displacing many other vegetation. Disperses spores into the wind to reproduce.
Photo credit: Peter de Lange

Regional Pest Management Plan (RPMP) status

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

View more about the RPMP statuses

General description

Tree fern < 12 m tall. Sori do not have indusium.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell rough tree fern. As rough tree fern 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 rough tree fern 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 rough tree fern 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.


Forest and riparian margins, gullies, light gaps, roadsides, disturbed sites.


Spores dispersed by wind.

Impact on environment

Highly efficient competitor that may displace vegetation. Can alter nutrient cycling.


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. Ensure correct identification and it is not a native tree fern.

Recommended approaches

Physical control

Method: Dig out.

Plant parts requiring disposal: Spores on leaves.

Disposal options: Remove to greenwaste or landfill if practical.


Biocontrol is currently not available for this species.

Community agrichemical control recommendations

No qualifications: Cut stump and paste freshly cut base of stems with metsulfuron gel.

Basic Growsafe certified: Cut stump and spray freshly cut base with 1g metsulfuron-methyl per 1 L of water.

Certified Handler/Experienced agrichemical user: Foliar spray seedlings with 5g metsulfuron-methyl per 10L of water and 20ml penetrant.

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