Surveys by the Department of Agriculture and Food have confirmed hatchings of Australian Plague Locusts inthe central and eastern Wheatbelt.
Growers in the Shires of Dowerin, Kellerberrin, Koorda, Merredin, Mukinbudin, Narembeen, Nungarin, Trayning, Westonia, Yilgarn and Kondinin are reminded to closely monitor and control locusts if pastures and crops are at risk.
Department invasive species project manager Martin Atwell said late rainfall through parts of the eastern wheatbelt had prolonged remnant green feed and increased the chances of locusts surviving.
"Experience from previous years suggests that late maturing green crops or areas of green pasture could be at risk of potential damage by locust nymphs and adults," Mr Atwell said.
"In the central agricultural region, many crops will soon be ready for harvest and be too dry to attract locusts.
"The department can provide advice and recommendations to landholders that need to undertake locust control spraying."
Department entomologist Svetlana Micic said growers looking to spray locusts should first monitor pest density levels and their movement to assess potential damage relative to pasture and crop maturity.
Ms Micic said a number of registered chemicals were available to control locusts and had specific withholding periods for stock and harvested crops intended for both domestic and export markets.
The withholding period listed on insecticide product labels for grazing is only for animals destined for the domestic market, not the export market. Export markets require different withholding periods for different chemicals.Specific information on insecticide withholding periods is available in the 'Locust spraying and withholding periods' information sheet and the 'Registered or permitted chemical guide for APL'. Information on identification, monitoring and control is available from the department's web site www.agric.wa.gov.au/locusts