Biocontrol introduction
Target pest: Ulex europaeus (Fabales: Fabaceae), gorse
Agent introduced: Scythris grandipennis (Lepidoptera: Scythrididae), gorse hard shoot moth
Imported:
1992
Import source:
UK
Released:
1993
Release details:
Hill et al. (2000) - one hundred S. grandipennis pupae in webs were released at one site in Canterbury in spring 1993.
Landcare Research (2000b), Gourlay (2011c) - a small number were released at one site at Burnham, Canterbury; no further releases are planned due to rearing difficulties.
Establishment:
Harman et al. (1996) - Scythrus grandipennis has been recovered in the field but is not considered established yet.
Hill et al. (2000) - one adult was seen shortly after the 1993 release of pupae, but larvae have never been observed at the release site; S. grandipennis has probably not established.
Landcare Research (2000b) - failed to establish.
Landcare Research (2006c) - Scythrus grandipennis is not thought to have survived from the one very small release that was made.
Impacts on non-targets:
Hill et al. (2000) - despite difficulties rearing S. grandipennis in the laboratory, it was possible to complete adequate host-range tests that demonstrated a high degree of host-specificity.
General comments:
Landcare Research (2006c) - gorse hard shoot moth (S. grandipennis) was dropped from the gorse biocontrol programme in the early 1990s when it proved impossible to rear and the colonial hard shoot moth (Pempelia genistella) was looking like a much better candidate.
References
Gourlay H (2011c). Gorse colonial hard shoot moth: Pempelia genistella. The Biological Control of Weeds Book - Te Whakapau Taru: A New Zealand Guide (Landcare Research) [Updated 2020] https://www.landcareresearch.co.nz/discover-our-research/biodiversity-biosecurity/weed-biocontrol/projects-agents/biocontrol-agents/gorse-colonial-hard-shoot-moth/
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
Hill RL, Gourlay AH, Fowler SV (2000). The biological control program against gorse in New Zealand. In Proceedings of the X international Symposium on Biological Control of Weeds 2000 Jul (Vol. 917, pp. 909-917). Montana State University Bozeman, Montana, USA. https://www.landcareresearch.co.nz/assets/researchpubs/biologial_control_gorse_Hill_2000.pdf
Landcare Research (2000b). Who's who in biological control of weeds? Patua Te Otaota - Weed Clippings. Biological Control of Weeds Annual Review 1999/2000. August 2000, 6: 10-11 https://www.landcareresearch.co.nz/assets/Publications/Weed-biocontrol/weedcp00.pdf
Landcare Research (2006c). Our gaggle of gorse agents. What’s New In Biological Control of Weeds? May 2006, 36: 6-7 https://www.landcareresearch.co.nz/assets/Publications/Weed-biocontrol/wtsnew36.pdf
