Fall armyworm

Fall armyworm, Spodoptera frugiperda, is a highly invasive pest that was detected in north Queensland in January 2020. It has the capacity to travel long distances relatively quickly and has been detected in NSW and WA. A detailed description of fall armyworm and the biosecurity implications of this pest is available in this bulletin from Vinehealth Australia.

While fall armyworm feeds preferentially on grass-type crops, many plants are susceptible, including horticultural crops. There is potential for fall armyworm to spread into grapegrowing regions; however, the development and behaviour of this insect in vineyards is not yet known.

Characteristics
Fall armyworm is the name commonly attributed to the larval stage of the moth Spodoptera frugiperda. Other Spodoptera species already found in Australia include the lawn armyworm and the dayfeeding armyworm. More information about their characteristics can be found in:

There is very limited published information on this pest’s development, feeding behaviour and ability to damage grapevines. As a result, the potential impact on Australia’s vineyards is not known.

Monitoring
Prior to applying a chemical treatment, growers are required to regularly scout crops to monitor for eggs and larvae. Treatments should be applied when pests appear, targeting eggs at the time of hatching or small larvae (prior to third instar stage) before the pest becomes entrenched. Permits should be read and instructions followed prior to spraying.

Fall armyworm is a notifiable plant pest. Any sightings resembling fall armyworm must be reported to the Exotic Plant Pest Hotline on 1800 084 881.

Management
The Australian Pesticides and Veterinary Medicines Authority has a broad range of chemical classes listed under permit for use against fall armyworm in grape production (shown in Table 1 below, along with the recommended restriction on use for export wine). This information is provided to inform the Australian grape and wine sector and should not be interpreted as an endorsement of any product.

Table 1. Chemical control options for fall armyworm in wine-grape production

Active constituent Activity group Some registered products Restriction on use for export wine Permit number
methomyl 1A Electra 225, KDpc Metho, Landrin 225, Lannate L, Lymo 225, Methomyl (225, 225 SL), Nudrin 225, Pirate, Seneca (Ultra 400SP), Sinmas 225 Not recommended on grapes destined for export wine. Contact your winery prior to any methomyl application. 89293
chlorantraniliprole 28 Altacor Hort Use no later than E-L 25, 80% capfall. 89259
spinetoram 5 Delegate Use no later than E-L 31, berries pea-size (not > 7 mm diameter). 89241
spinosad 5 Entrust Organic 89870
emamectin 6 Energise, Proclaim, Proclaim Opti, Warlock Use no later than E-L 31, berries pea-size (not > 7 mm diameter) AND do not use within 56 days of harvest. 89263
indoxacarb 22A Avatar, Incarnate 300 WG, Indoxacarb 300WG, Lepta 300 WG, Persona 300 WG, Spymaster 300WG 89278
Bacillus thuringiensis subspecies aizawai 11 Bacchus WG May be used until harvest
Bacillus thuringiensis subspecies kurstaki 11 Delfin, DiPel DF May be used until harvest