Description of adult
- Bright yellow hind wing with a marginal dark brown or black band.
- Makes a distinctive clicking noise when flying.
- In the solitary phase populations are predominantly green but when in the gregarious phase. (swarming) populations are predominantly brown.
- Males are 25 to 35 mm, females are 35 to 50 mm in length.
Description of nymph
- In profile the thorax is domed well above the head.
- Hind femur (thigh) is banded.
- General body is grey-black in colour.
Habitat
Prefers moist coastal and sub-coastal regions and is commonly found in the tropics and sub-tropics.
Found in association with a variety of grasses, both native and introduced. It is common in the rangelands, pastures, lawns and in parks.
Life cycle
- In temperate regions this locust has one generation but can have up to three generations in tropical regions.
- Egg pods are laid on bare, compact soil, especially in overgrazed pastures.
- In tropical regions:
- Eggs hatch after 17 days, producing nymphs.
- Nymphs take 40-50 days to become immature adults.
- Immature adults take a further 12-14 days to mature and lay eggs.
- Adults are usually noticed from September to April.
- At high population densities, nymph bands and adult swarms can form.
- Adult swarms are infrequent, localised and spread slowly.
- As the dry season starts, numbers of locusts will decrease.
Control considerations
- Control should only be considered to protect high value crops.
- Control of yellow-winged locust is the responsibility of the landholder.
- This locust species is not declared in Western Australia.
- Nymph bands can be sprayed with boom sprays, this is the most effective control method.
- Spraying in the late afternoon is more effective, as nymphs tend to spread out during the day.
- Dense, high pasture or crops should not be sprayed in still conditions, as wind turbulence is needed for spray to penetrate foliage.
- Nymphs die after contact with, or ingestion of, treated vegetation within 2-48 hours after spraying. Follow-up treatments may be necessary for up to 2 weeks after spraying, as not all eggs hatch at the same time.
- Once locusts are flying, aerial spraying of agricultural chemicals is the only efficient control method. However, locusts can migrate back into sprayed areas.
Chemical control options
- Landholders are reminded to comply with label regulations, particularly the withholding periods for grazing and export intervals. Label withholding periods only apply to domestic markets; refer to SafeMeat for export withholding period (EAFIs, ESIs and EGIs).
- Fenitrothion has a registration for yellow-winged locust control at 200-300 mL/ha.
- Use of permitted chemicals is restricted to crops for which there are current registrations for other pests. Chemicals registered for spur-throated locust and Australian plague locust will also have efficacy on yellow-winged locust nymphs. However, rates of application must not exceed the label rate for each crop.