Macadamia pest continues reign of terror from orchard to orchard

The spread of the macadamia felted coccid (MFC) is continuing across South Africa’s macadamia nut orchards as crop protection options remain evasive.

Speaking at the AmberMacs expo in White River, Mpumalanga, Dr Schalk Schoeman, research extension manager at SA Macadamias (SAMAC), lamented that the pest was behaving contrary to previous research.

“All research literature to date states that this coccid is a very slowmoving pest, yet we have seen rapid spread in South Africa from one orchard to the next, and one region to the next,” said Schoeman.

The MFC was introduced to South Africa from Australia through illegally imported plant material around 2019. The pest has had severely detrimental effects on orchards in Australia and Hawaii, causing mass tree dieback. So far there has been little progress made in controlling the pest in those countries. It was first detected in the Barberton area of Mpumalanga and has moved across Limpopo and KwaZulu-Natal.

SAMAC has been working on various options since the outbreak, including collaborating with Hawaiian and Australian researchers. Schoeman said although parasitoids had been used successfully in Hawaii, with 80% success, they only produced a 5% success rate in South Africa.

He said even when pest numbers were under control, research showed that the trees took time to reach pre-infestation yield levels.

SAMAC is in the process of importing a parasitoid from Australia which has shown success. In the meantime, Schoeman said farmers needed to focus on understanding and controlling the different life cycles of the MFC. –