Regional Pest Management Plan (RPMP) status
- Parkland with Significant Ecological Areas — Site-led (on-park only)
- Whole region — Sustained control
- Waitākere Ranges Heritage Area priority status
- National Pest Plant Accord Species
Evergreen perennial with woody rhizomes. Leaves are < 40 cm long, erect and often in a flattened fan. Flowers are blue and borne in clusters of 5-7. Capsules are dehiscent and three-sided, with dark red-brown seeds.
What you need to know
To help protect our environment:
- You must not breed, distribute, release or sell aristea. As aristea 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 aristea 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 aristea 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.
Open and disturbed sites, roadsides, forest, scrubland, coastlines, herbfields, rocky and bare sites.
Seeds dispersed by water. Vegetative spread from rhizomes, dispersed by water. Human-mediated dispersal through contaminated soil on footwear and machinery.
Impact on environment
Forms dense stands, preventing native seedling establishment. May facilitate introduced shrub, vine and grass succession in forests.
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.
Method: Dig out.
Plant parts requiring disposal: All parts.
Disposal options: Compost in a composting weed bag or remove to greenwaste or landfill.
Biocontrol is currently not available for this species.
Community agrichemical control recommendations
Basic Growsafe certified:
For small infestations: Foliar spray with 3g metsulfuron-methyl plus 150ml glyphosate per 10L of water.
Certified Handler/Experienced agrichemical user:
For medium to large infestations: Foliar spray with 3g metsulfuron-methyl plus 150ml glyphosate per 10L of water and 10ml penetrant.
Caution: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.