Target pest: Ulex europaeus (Fabales: Fabaceae), gorse
Agent introduced: Aceria genistae (Acarina: Eriophyidae), broom gall mite
Harman et al. (1996) - accidental introduction. [NB: a strain specific to broom was deliberately imported in 2006 (see 'General comments' section).]
Harman et al. (1996) - first recorded in New Zealand in 1985.
Harman et al. (1996) - Aceria genistae is widespread on gorse.
Impacts on target:
Harman et al. (1996) - has little apparent impact on growth of gorse.
Gourlay (2010a) - Aceria genistae was introduced into New Zealand in 2006 as biocontrol agent against broom (Cytisus scoparius), subsequent to it being recorded in New Zealand on gorse. Recent research shows that A. genistae includes a number of distinct strains, each of which is specific to one species of plant. The mites being introduced against broom are specific to broom and are unlikely to interbreed with the resident strain on gorse.
Gourlay H. (2010a). Broom Gall Mite. In The Biological Control of Weeds Book (Landcare Research) https://www.landcareresearch.co.nz/discover-our-research/biosecurity/weed-management/using-biocontrol/the-biological-control-of-weeds-book/
Harman HM, Syrett P, Hill RL, Jessep CT. (1996). Arthropod introductions for biological control of weeds in New Zealand, 1929 - 1995. New Zealand Entomologist, 19(1): 71-80