By Joshua Kato
The major pests likely to cause problems in young trees are:
· Macadamia felted coccid
· Scale insects (mainly latania scale and long soft scale)
· Macadamia twig-girdler
· Macadamia leaf miner
· Redshouldered leaf beetle (monolepta beetle)
The only major disease of young trees is trunk canker. These eat away at the stems. Pull back affected bark and wood with a sharp knife, and thoroughly soak trunks with a registered copper fungicide mixed with white, water-based paint. This helps to maintain contact with the fungicide and seals the wound. Where cankers are more extensive, and paring back affected bark and wood is impracticable, spray affected areas with metalaxyl and copper oxychloride. Alternatively, spray affected trees with phosphorous acid. Repeat the treatment two to three months later.