Native budworm

Native budworm (Helicoverpa punctigera) is a major pest of many crops and pastures over spring. The larvae are up to 40 mm long with substantial colour variation, usually with darkish strips along the body and bumpy skin with sparse stiff black hairs. Newly hatched larvae (approximately 1.5 mm in length) are light in colour with dark brown heads and spots, and as they develop they become darker in colour.

TOPCROP agronomist, Michelle Pardy (Vic DPI), says that high levels of budworm activity continue to be reported in many parts of Victoria; with spraying continuing in some areas where yield potential is still reasonable. Agronomist, Kate McCormick (John Stuchbery and Associates), reports that many crops have recently required chemical control for native budworm in the Mallee district of Victoria, although there have been far less crops sprayed than in previous years. For example, in lentils, Kate estimates about 50% of the crops have needed spraying, while the remaining paddocks have not been sprayed due to low budworm numbers and/or poor crop conditions. 

The following native budworm pheromone trapping information for October 6^th – 15^th has kindly been provided by The Victorian Department of Primary Industries.

Region	Trap Sites	Moth count 10 days	Crop & Growth Stage	Comments
Mallee	Walpeup Berriwillock	0 0	Peas - close to harvest Lentils - sprayed	Preceding week - hot/windy, no rain
Wimmera	Warracknabeal Brim	481 452	Vetch - stressed Beans - stressed	Hot/windy
North Central	Kerang Elmore	162 20	Faba Beans Lupins - flowering	Dry
South West	Hamilton	70	Peas - flowering	22 mm rain

Remember, moth numbers, and the subsequent generation of grubs, will vary between regions and paddocks, so monitoring remains the best way to determine the risk native budworm pose to individual crops.

It is unlikely that crops will be significantly damaged by caterpillars hatching from the most recent egg-laying, due to the conclusion of flowering and hardening of pods. However, growers should continue to monitor individual paddocks for caterpillar activity in ripening crops and assess this against the cost of spraying.