Pacific Pests, Pathogens and Weeds

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Summary

• Widespread distribution. Especially woody plants. Common on avocado, breadfruit, Casuarina, citrus, Ficus, guava. Hosts occur in more than 60 plant families. Many hosts. An important pest.
• Females produce living young. Males rare.
• Outbreaks cause leaves to yellow and shoots to die.
• Honeydew from these sap-sucking scales falls onto leaves and fruits, to be turned black by fungal moulds.
• Natural enemies: ladybird beetles (Rodolia) important.
• Cultural control: prune infested stems, branches and fruits, and burn; add fertilizer, manure or compost to improve tree health; assist natural enemies: destroy ants' nests (hot water), prune low branches, and weed.
• Chemical control: soap, white or horticultural oils; priority is to remove ants to let natural enemies work: use synthetic pyrethroids.