Chemical use and crop residues

Managing Australian plague locusts

Populations of the Australian plague locust (APL) occur episodically in Victoria. They most often migrate into Victoria from their home breeding ranges in New South Wales and Queensland but can also breed further generations within Victoria. In heavy outbreak years they can cause severe economic damage to agricultural and horticultural crops and the amenity of our rural areas.

Control of APL can be difficult, particularly at the adult stage when they are highly mobile and moving in swarms. Eggs which are laid in the soil cannot be effectively controlled. Egg beds may be difficult to spot and could range over large areas. When they hatch, damaging populations can arise in a very short time.

The most effective means of managing APL is to spray the non-flying second and third nymphal stages, when the hoppers have started to band together. This occurs around two weeks after hatching in warm weather.

Widespread aerial spraying is usually deployed for large open spaces and managed by the Australian Plague Locust Commission (APLC) in collaboration with state government authorities. However, in densely populated mixed crop and forested areas, this is the least preferred option.

Control authorities use licenced ground operators to mix and apply control chemicals. Landholders must apply the same level of professional care.

Producers of crops harvested for human consumption, and products derived from animals for human food (meat, eggs, milk), should obtain information about the chemicals which may be applied to control locusts, regardless of whether they are controlling the locusts themselves or control is being undertaken by an outside authority.