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2022 Weed Biocontrol articles

  1. It’s time to take on purple loosestrife

    Purple loosestrife (Lythrum salicaria) has been a tantalising biocontrol target for many years, but up until recently this weed was an eradication or progressive containment pest in all regions of the country. This work was undertaken by regional councils and unitary authorities as part of their loc...

  2. Aerial surveillance for detecting new weed incursions

    Manaaki Whenua – Landcare Research (MWLR) was recently contracted by the Department of Conservation (DOC) and the Ministry for Primary Industries to collect aerial footage of a new invasive weed, sea spurge (Euphorbia paralias), which was seen along New Zealand’s West Coast for the first time in 201...

  3. Climate in the heather beetle story

    When surveying for candidate biocontrol agents, every effort is made to climate-match collection sites with the intended destination, but compromises often need to be made or best-case scenarios are not realised.

  4. Comparing nodding thistle then and now

    High-quality impact monitoring of weed biocontrol can be ideal for selected flagship projects, but it is an expensive undertaking. Also, although stakeholders like to see monitoring programmes undertaken, they have to balance their investment of resources in monitoring versus supporting new or exist...

  5. Summer activities

    Summer is a busy time for many biocontrol agents, so you might need to schedule the following activities.

  6. Keeping Track of the Adventive Plant Species in New Zealand

    New Zealand (NZ) has a rich adventive seed plant (seed-bearing plant or Spermatophyte) flora, outnumbering the native seed plant flora by over 600 species. A total of 3950 seed plant species are permanently established in the wild in NZ, 1815 of which are endemic, 320 are indigenous but not endemic ...

  7. Predation and the Tradescantia Leaf Beetle

    The success of the tradescantia leaf beetle has been highly variable in several regions of the country. Beetle predation has been implicated in their failure to establish at some sites. Invasive common and German wasps, paper wasps, shield bugs and stink bugs, and spiders are all suspected to be pot...

  8. A Fresh Search for Old Man’s Beard Pathogens

    In 1996 a leaf fungus called ‘Phoma clematidina isolate’ was collected in the USA and released in NZ for the biocontrol of old man’s beard (Clematis vitalba). This fungal isolate initially caused significant damage at some of the release sites, but after some time it became evident that it had not p...

  9. It Established After All!

    The boneseed leafroller is a moth that was released as a biocontrol agent for boneseed in NZ in 2007. Significant effort went into mass-rearing the moth for widespread releases between 2007 and 2008, but establishment in the North Island was limited, and, after lots of unsuccessful searching, was de...

  10. How Damaging is the Broom Gall Mite?

    Scotch broom was first recorded growing outside of cultivation in NZ in 1872 and has since spread throughout the South Island and lower North Island. Its range expansion has been most pronounced over the past 70 years, particularly very recently on the Central Plateau of the North Island.