Calicotome spinosa

Spiny broom

Family: Leguminosae

Origin: Mediterranean

Close up of spiny broom leaves.
Bears yellow pea-like flowers that turn into green pods once pollinated. Branches have long thorns on them and seed pods have small spines at the tip.
Photo credit: Trevor James, AgResearch

Regional Pest Management Plan (RPMP) status

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

View more about the RPMP statuses

General description

Many-branched perennial shrub < 3 m tall. Stems bear spines < 4 cm long. Leaves comprise three leaflets < 12 mm long. Flowers are yellow, < 15 mm long and borne in spring-summer. Seed pods are < 4 cm long, flattened and hairless, with a small spine at the tip.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell spiny broom within the Auckland region.
  • You must not plant spiny broom 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 spiny broom 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

Rocky soils, grassland, pasture, open woodland, roadsides, disturbed areas, wasteland.

Dispersal

Seeds dispersed by explosive dehiscence and contaminated soil on animals. Human-mediated dispersal through contaminated soil on machinery and vehicles and dumping of garden waste.

Impact on environment

Forms dense stands, excluding and competing with native vegetation. May reduce pasture grazing potential and outcompete plantation tree seedlings. Nitrogen fixer. May facilitate other exotic species.

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: All parts.

Disposal options: Remove to greenwaste or landfill.

Biocontrol

Biocontrol is currently not available for this species.

Community agrichemical control recommendations

Certified Handler/Experienced agrichemical user: Foliar spray with 200ml glyphosate green per 10L of water and 20ml penetrant when in full leaf or foliar spray with 5g metsulfuron-methyl 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.

A spiny broom seed pod.
A perennial shrub that grows up to 3m tall. Has roots that can fix nitrogen in the soil so is adapted to grow in poor soil conditions.
Photo credit: Trevor James, AgResearch
An overgrown spiny broom bush.
Seed pods mature over summer and start to dry out. Once completely dry they pop open and seeds are exploded away from the plant.
Photo credit: Trevor James, AgResearch
The yellow flowers of spiny broom.
Plants are not browsed by cattle so they are able to take over pasture areas. Can form dense populations which can out-compete native brooms.
Photo credit: Trevor James, AgResearch