Life after endosulfan, the Australian macadamia experience

Abstract

As of October 2012 the use of endosulfan was prohibited in Australian Horticulture. Within the macadamia pest management system endosulfan had been a mainstay of production for NSW growers in particular since the mid-1980s. It offered a compromise between a residual flower spray with miticide properties and a low bee toxicity not found in other pesticides of that generation. Some pesticide free crops had been grown prior to 2012 but recent changes to pest distributions in these areas have put pressure on the feasibility and profitability of that approach. Outbreak populations of pests like macadamia lace bugs (especially Ulonemia decoris Drake), and macadamia seed weevils (Sigastus sp.) have developed in many macadamia crops in the NSW growing districts since late 2008 (50% of Australian production area). These threaten production even in areas with good spray coverage and monitoring. These pests are migrating freely from abandoned orchards causing almost total crop loss in some instances. The APVMA needs to realise how reliant the Australian macadamia industry (30% of world production) is on access to effective chemistry. Without endosulfan, new chemistry for managing Scirtothrips albomaculatus and Polyphagotarsonemus sp. (broad mites) on the expanding macadamia buds in autumn is required because multiple pyrethroid and organophosphate applications will generate more activity. Abamectin appears to be the most effective short term solution.