THE EXOTIC pest fall army worm has pushed its way south and has been observed in its larvae stage in Victoria for the first time.
The pest, first found in Australian in 2020, however, is not causing significant damage as yet, with other home grown species creating larger crop losses at this stage.
Pest monitoring service PestFacts has reported multiple cases of chewing damage by fall army worm moth larvae in maize crops in diverse locations in Victoria recently.
Julia Severi, PestFacts extension scientist, said fall army worm damage had been reported in Victoria in the geographically distant regions of Gippsland and the north of the state.
She said there had been fall army worm damage around Yarram, Warragul and Sale however the crop damage is not extensive, with a few plants in localised areas displaying feeding symptoms.
But other species have been far more damaging thus far.
Near Fish Creek, also in Gippsland, corn earworm larvae were identified causing estimated damage of up to 40 per cent in a maize crop.
In the north of the state fall armyworm larvae have also been found near Echuca, where they were reported to be causing leaf damage in maize.
Ms Severi said the infestations of fall army worm in the temperate south was caused by the mild and wet spring.
The pests are a subtropical species and cannot survive southern winters, however Ms Severi said fall army worm was highly mobile and could migrate to the south if there was food and suitable conditions.
Ms Severi said while fall army worm moths were detected in Victoria in 2021 this year was the first time PestFacts had received reports of larvae in field crops.
The damage has been far more severe in subtropical and tropical regions in northern Australia, where high rates of crop loss in susceptible species such as maize or cane can occur within days of an infestation.
Ms Severi said that in the south there could be problems with the pest through late summer and early autumn but by May night time temperatures would likely be too cold for them to grow further, although the exact timing of the reprieve would depend on the seasonal conditions.