Native budworm update to October 2026

PestFacts SA has received several reports of spray failure using synthetic pyrethroids against budworms in peas in the mid north – mostly native budworm and an occasional lesser budworm.

No cotton bollworm (Helicoverpa armigera) caterpillars have been seen, and even the few moths caught in the armigera pheromone traps were all identified as native budworm (H. punctigera).

No spray failures have been reported in other crops.

It is not clear if spray failure is caused by resistance development, but this seems unlikely as native budworm usually migrates each season from the outback. It is more likely that spray failure is due to low spray volumes on a very leafy crop, where caterpillars sometimes hide in pods. If follow-up spraying is required, be aware that harvest is approaching, and choose a product from another chemical family, such as Chlorantraniliprole or similar – see the Australian Pesticides and Veterinary Medicines Authority's (APVMA) Public chemical registration information system search for registered products. Make sure you apply a larger volume to cover the vegetation.

The latest results from our native budworm trapping network up to 21 October show low activity since the last report. Be aware that local flights might still occur, resulting in egg lay and developing caterpillars. In most cases, it will now be too late for effective insecticide application, but crops are likely to be approaching maturity and are becoming less attractive for egg laying.