Chemical treatment advice
Seek professional advice
If undertaking chemical control of locusts, landholders must ensure all activities are carried out safely, responsibly and in accordance with relevant legal requirements.
The information below is provided as a starting point so that you can have an informed conversation when seeking advice or purchasing chemicals.
Before undertaking locust control, you are encouraged to seek advice from:
- agronomists
- chemical resellers
- PIRSA
- other appropriately qualified advisers.
PIRSA does not recommend any particular product. Professional advice can help ensure the most effective and appropriate treatment option for the situation.
Selecting chemicals
The Australian Pesticides and Veterinary Medicines Authority (APVMA) has approved several chemicals and biological products to control locusts.
The most suitable option depends on your:
- use situation – crop, pasture or non-crop areas
- location
- application method – aerial, ground, mister, spot spray
- development stage of locusts – nymphs or adults
- environmental considerations – buffer distances, sensitive environments or sites.
Always read and follow the product label or permit before use as labels, registrations and permit approvals and instructions can change.
Follow all mandatory label directions.
Ensure you comply with any spray drift restraints and withholding period requirements for harvest and livestock grazing.
Note: Fenitrothion and some other chemicals available during the 2010 locust outbreak are no longer approved for Australian plague locust control.
Malathion is registered for locust control in cereals, pastures and non-crop areas.
Some Malathion product labels state "ground application only" – check if the product is approved for aerial use if that is your intention.
Check each Malathion label for specific instructions.
- Do not graze or cut for stock food for 1 day after application to cereals, pastures, and forage crops.
- Do not harvest for 1 day after application to cereals, pastures, and forage crops.
- Breaks down quickly after application.
- Effective at low application rates.
- Highly toxic to bees and aquatic life.
- Do not spray near waterways or when bees are foraging.
Carbaryl is registered for locust control and is suitable for cereals, pastures and non-crop areas.
Carbaryl is not approved for aerial application.
Check each Carbaryl label for specific instructions.
- Cereals: do not harvest for 14 days after application. Do not graze or cut for stock food for 4 days after application.
- Pastures and lucerne: do not graze or cut for stock food for 7 days after application.
- Highly toxic to bees and aquatic life.
- Do not spray near waterways or when bees are foraging.
These chemicals are all synthetic pyrethroid pesticides that are permitted for locust control in a range of cereal and pasture situations.
The chemicals' product labels do not have direct recommendations for Australian plague locusts but recommendations are available on some permits approved by the APVMA. Note that efficacy for locusts will be based on observation and not stated on the label.
These products may be applied by either air or ground application – check specific labels for details.
Check each label for specific instructions.
- Cereals: check specific label for 'do not harvest' and 'do not graze' withholding periods.
- Pastures and lucerne: check specific label for 'do not harvest' and 'do not graze' withholding periods.
- Dangerous to bees and aquatic life.
- Do not spray near waterways or when bees are foraging.
Fipronil can only be used in pasture and sorghum crops. It must not be used in cereal or pulse crops.
Fipronil is approved for ground and aerial application to pastures.
Fipronil affects the locusts' nervous system. Locusts are exposed when they come into contact with the chemical or consume treated vegetation.
- Do not graze for 14 days after application to pasture.
- Effective at low application rates.
- Lower use rates reduce risks to mammals.
- Extremely toxic to bees and aquatic life.
- Do not use near waterways or when bees are foraging.
Metarhizium, sold as Green Guard, is a naturally occurring fungus used to control locusts.
It infects locusts after contact and takes 1 to 3 weeks to kill them.
Metarhizium is a useful option where conventional insecticides are not suitable, such as near waterways or in environmentally sensitive areas.
Works best:
- in warm weather
- on young locusts (nymphs or hoppers).
Metarhizium is available in several formulations, including products for ground or aerial application.
Check Agricultural and veterinary permits search for the latest approved APVMA permits.
The SAFEMEAT website has advice on chemical residue risks to livestock, use of national vendor declarations and export slaughter intervals – see Plague locusts, wingless grasshoppers and livestock residue.