Tradescantia

Tradescantia is a perennial mat-forming herb less than 60cm tall. It smothers native vegetation and reduces native seedling abundance and species' richness.

Description

• Leaves are shiny, less than 6cm long, and alternate.
• Flowers are white and visible in clusters in December – January.
• Vegetative spread from stem fragments, dispersed by water and livestock.
• Human-mediated dispersal through dumping of garden waste and contaminated footwear, soil and machinery.
• Habitats include forests, forest margins, cliffs, bluffs, and riverbeds.

What you need to know

Forms dense mats, smothers and inhibits native vegetation regeneration. Reduces native seedling abundance and species' richness. Potential to transform forest structure, composition and function.

Management approach

Tradescantia is declared an unwanted organism by the Ministry for Primary Industries (MPI) because it is capable of causing harm to the natural environment, physical resources or human health in Aotearoa/New Zealand.

These species pose a high risk to our environment, economy, recreation, and cultural values.

Rules

Any species declared a pest, including unwanted organisms, cannot be sold or be in a place where plants are being sold. Pest plants cannot be propagated, bred, multiplied, communicated, released, caused to be released, or otherwise spread.

Consider removing this invasive species from your property and consult your local council for appropriate disposal. Consider lower-risk alternatives for your garden, such as native plants.

Control

Site management

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

Physical control

Rake, roll up or pull out.

Plant parts requiring disposal: All parts.

Compost in a composting weed bag for 12 months or more and tip out compost once all stems have decomposed and reuse the bag or contact your local council for appropriate disposal locations.

Chemical control

Certified handler/experienced agrichemical user: For infestations near water, foliar spray with 400ml glyphosate green per 10L of water.

For terrestrial infestations, foliar spray with 60ml triclopyr per 10L of water and 20ml penetrant in spring or summer.

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

Biological control

Check for the presence of agents:

• Tradescantia leaf beetle (Neolema ogloblini)
• Tradescantia stem beetle (Lema basicostata)
• Tradescantia tip beetle (Neolema abbreviata)