Project overview
Tradescantia is native to South America. It was brought to New Zealand as an ornamental plant, but it has become a major weed throughout the North Island and parts of the South Island. It forms dense mats in forest margins, forest clearings, and stream margins, smothering tree and shrub seedlings and low-growing native plants.
Four biocontrol agents from Brazil have been released to attack tradescantia. Three are beetles: the tradescantia leaf beetle (Neolema ogloblini) damages the foliage, the tradescantia stem beetle (Lema basicostata) attacks the stems, and the tradescantia tip beetle (Neolema abbreviata) attacks the growing tips. All three beetles have established and are showing early promise. The beetles cause extensive damage to tradescantia in their native range, and it is hoped they will do the same here.
A yellow leaf spot fungus (Kordyana brasiliensis) has also been released in New Zealand in 2018 and is establishing well in damp areas. The fungus is expected to complement the beetles, especially since it will likely thrive at sites that flood regularly.
