Western Australian broadacre property owners have been encouraged to keep monitoring crops and pastures for signs of Australian plague locust (APL) activity, despite relatively low activity this spring.
The delayed start to the growing season and protracted cold and wet conditions during spring have delayed hatchings in some areas of the Grainbelt.
There have been localised reports of APL hatchings from Southern Cross, Narrogin, Katanning, York, Jennacubbine and Cadoux, posing a risk to some crops and pastures that are still green.
Department of Primary Industries and Regional Development research officer, Svetlana Micic, said it was important for landholders to monitor hopper and adult locust numbers and to undertake control measures, if required.
“While hoppers tend to generally avoid established green crops, when locusts begin to fly crops that are beginning to hay off are most susceptible to damage,” Ms Micic said.
“Locusts will hatch at variable times so it is important for growers to continue to monitor crops and pastures that are still green to determine if and when to start spraying.
“The main activity will be seen in pastures so look for early hatchings and hatching egg beds in places where there are bare patches, such as around dam banks, road catchments and along fencelines.”
Ms Micic said treatment measures to protect pastures were recommended, if the cost of controlling the pest exceeded the cost of replacing the feed.
“The threshold for treating pastures is 20 hoppers per square metre or 10 adult APL/m²,” she said.
“Landholders who observed APL on their properties last autumn need to be particularly vigilant, as there are likely to be egg beds hatching now.”
While it is up to landholders to control locusts on their properties, department officers will be monitoring for APL over spring and summer and providing advice on treatment measures.
Landholders are reminded to comply with label regulations, particularly the withholding periods, when treating locusts.
For more information on locust identification and control options click here.