Plant Doctor Archive

Codling moth on fruit trees

Question WITH our property we have inherited a couple of apple and pear trees. Over the past few years they have never been free of codling moth. Can you please advise how we can rid these poor plants from this pest? I am happy to use sprays but an organic alternative would be interesting.

Answer FRUIT is damaged when the young codling moth caterpillar hatches and enters the fruit. An insecticide such as Carbaryl can be used as soon as petals fall in spring. Do not spray while in flower as Carbaryl is toxic to bees. Repeat spray at fortnightly intervals; cease spraying one month before harvest.

The best time to control codling moth is when the adults are flying, from September to November, using yellow pheromone traps. These are sticky traps that are hung in the tree and contain a pheromone which attracts the female. The female gets stuck and cannot lay her eggs. These traps are available from garden centres and hardware stores under the Trappit brand.

A band of cardboard can be put around the trunk or branches to trap larvae as they come down the tree to pupate — burn the bands in winter.