An extended season for native budworm

As long as pods are green in pulses and other legumes, keep your sweep net at hand.

Exceptional native budworm (Helicoverpa punctigera) moth activity in many areas, as measured by catches within a network of pheromone traps, has not been mirrored by an intense wave of caterpillar activity this season.

In the Riverina, sweep netting for budworm in faba beans, field peas and broadleaf lupins has revealed only low numbers.

Similarly, in Victoria’s Northern Country, field peas have been sampled extensively but no caterpillars were observed.

There are many factors that can be attributed to the low caterpillar infestations, particularly the wet and cold conditions that reduce egg and neonate survival rates.

With the slightly warmer conditions predicted this week, populations are expected to increase.

Canola is likely to be windrowed over the next 2-3 weeks in northern Victoria and NSW and is now unlikely to be affected by native budworm.

We predicted that 3^rd instar caterpillars would first start to appear from late September to mid-October (depending on location), based on the arrival of the first large moth flight for the season.

While this was the case, large moth flights have persisted through September and October in the Victorian Mallee and Wimmera, and peaked in early October in NSW (Table 1).

High moth numbers in lupins around the Wellington region of the NSW Central West Slopes & Plains have also been reported.

Despite the patchy caterpillar numbers to date, we strongly recommend that monitoring of pulse and canola crops continue until they fully mature.

Once pulses and canola have been harvested, some summer crops that remain at risk include lucerne, soybeans, sunflower, safflower, annual medic and clovers, and cotton.

Trap location	District	9th Sep	16th Sep	23rd Sep	30th Sep	7th Oct	14th Oct	21st Oct
Ouyen	Mallee, VIC	125	942	662	527	846	239	9
Swan Hill	Mallee, VIC	131	181	303	351	466	281	440
Kerang	Mallee, VIC	183	306	516	108	296	198	51
Rupanyup	Wimmera, VIC	35	413	116	63	730	174	230
Warracknabeal	Wimmera, VIC	0	0	0	0	0	0	0
Wonwondah	Wimmera, VIC	2	75	na	250	250	0	50
Forbes	Central West, NSW	0	22	573	79	114	na	na
Warren	Central West, NSW	11	1	3	0	37	5	1
Wagga Wagga	Riverina, NSW	0	0	na	na	168	na	33

Acknowledgements

We would like to thank the following trap operators:

Brad Bennett  – Consultant, AGRIvision (Victorian Mallee)

Jim Cronin – Agronomist, Landmark (NSW Central West Slopes & Plains)

Adam Dellwo – Agronomist, Elders (NSW Riverina)

Bill Gardner – Agronomist and Grower (Victorian Wimmera)

Shayn Healey – Agronomist, Crop-Rite Pty Ltd (Victorian Mallee)

George Hepburn – Agronomist, Tylers Hardware & Rural Supplies (Victorian Wimmera)

Damian Jones – Agronomist, Agronomic Results (Victorian Mallee)

Jake Leith – Agronomist, AGRIvision (Victorian Wimmera)

David White – Agronomist, Delta Agribusiness (NSW Riverina)

Sources of field reports

Jack Edwards – Agronomist, D & J Rural (NSW Central West Slopes & Plains)

Greg Toomey – Agronomist, Landmark (Victorian Northern Country)

David White – Agronomist, Delta Agribusiness (NSW Riverina)

Cover image: Photo by Andrew Weeks, Cesar Australia