Diamondback moth alert

Diamondback moth Plutella xylostella

There have been reports of a dramatic increase in the numbers of the diamondback moth. The adult moths are greyish brown in colour and have diamond markings on their backs. They are nocturnal and about 1cm, half inch in length. The adults pose no threat to crops. It is the emerging green caterpillars that do all the damage. They can devastate a crop with great speed. The target crop seems to be most members of the brassica family. The soft leaf tissue is stripped leaving the tougher leaf stalk and ribs.

The moth appears to be resistant to most pesticides. But it may be worth considering trying a biological caterpillar killer such as (Steinernema carpocapsae) to control the caterpillars. It is important to wait until the earliest hatchings are seen before using the product which is available from Nemasys, Agralan, Neudorff and Scarllets.

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