Joanne Taggat’s backyard in East Fremantle has been dubbed “ground zero” for the spread of a devastating polyphagous foraminifer pest in Australia.

The scientist first noticed unusual traces of the invasive South Asian pest on a fallen branch of his ash-leafed maple in early August 2021.

Within hours of reporting the discovery on a pest-tracking app, biosecurity officers and entomologists rushed to her home and determined that this would soon be the first confirmed case in the country.

Since then, the Department of Primary Industries and Regional Development has tried to stop the spread of the disease by destroying more than 3000 trees in Perth.

“They ran to see it and identified it very quickly. The department was on top of it. It was devastating to see it spread,” she said.

The official quarantine zone was expanded on Friday and now covers the entire Perth metropolitan area – reaching as far as Two Rocks in the north and Jarrahdale in the south.

The new boundaries expanded the area to include five local governments – Armadale, Kwinana, Mundaring, Rockingham and Serpentine-Jarrahdale.

The expanded zone has been divided into two parts: Zone A with more stringent regulations for more infested areas and Zone B with fewer restrictions.

“The expansion of the quarantine area will provide an additional buffer zone where we will increase pest surveillance and take immediate actions to control the pest in the area,” said Vincent Lanoiselet, Chief Plant Biosecurity Officer at DPIRD.

Ms Taggat urged Western Australians to remain vigilant, report any detections using the MyPestGuide Reporter app and adhere to the Department’s quarantine measures.

“I hope people spread the word as widely as possible. Be vigilant and release your app if you see anything because — in my experience and others I know — DPIRDs are very responsive,” she said.

“This will be a community effort. Everyone has a key role to play. We should all do what we can to support the government’s response.”

She planted the maples 40 years ago and named them after her granddaughters, Ella and Olivia, to educate them about trees and caring for the environment.

Ms Taggat said she hoped to take part in the Government’s tree replanting programme, which aims to replace trees lost to the pest.

More information on the extended quarantine area and individual zones can be found at agric.wa.gov.au/borer.

Report pest damage using the MyPestGuide Reporter app, call the Exotic Plant Pest Hotline on 1800 084 881 or visit the department’s website.