Hundreds of trees cut down as 'significant' outbreak poses huge risk to Australia

The area has been urgently quarantined until the destructive pest can be eradicated.

Australia's $24 billion commercial forestry industry is under threat following the discovery of an exotic pest in Adelaide that has seen a park closed and 300 trees destroyed.

The City of Tea Tree Gully in South Australia has notified the public of a serious outbreak of giant pine scale that has forced the Department of Primary Industries and Regions (PIRSA) to destroy hundreds of trees in Highbury and Hope Valley.

Locals have been told that certain areas, including the popular Elliston Reserve, will be closed until 2024 while experts attempt to eradicate the pest from South Australia. Those who attempt to go in and remove vegetation from the restricted area face a maximum $5000 fine under the Plant Health Act.

Pictured are felled trees in Highbury, Adelaide after a Giant pine scale infection. Source: Adelaide Now
Trees are removed in Highbury, Adelaide after a confirmed giant pine scale infection. Source: Adelaide Advertiser

Contagious and destructive pine pest

“The impact of the giant pine scale insect on our community is significant," General Manager, City of Tree Gully Operations, Felicity Birch has said in a recent statement. "We understand that it’s confronting for locals to see these established trees be removed so quickly, but it was a necessary measure to protect further losses elsewhere."

Australia has about two million hectares of sustainable, commercial plantation forestry, and Australia's forest industries contribute around $24 billion to the economy every year.

Giant pine scale is considered a biohazard due to how destructive it is and how easily it can spread through infested plant material, or by latching on to humans and their clothes. According to Forestry South Australia, an infestation can only be fully eradicated by quarantining the area of infection and destroying the host trees.

Giant pine scale pest not native to Australia

Giant Pine Scale is an insect from the eastern Mediterranean region that sucks the sap from pine trees, and any plants from the pine family exclusively, slowly killing the plants. Infection is easy to spot because the tiny insects excrete what looks like white cotton or snow.

This pest has not been detected in South Australia since 2018, but has been found in some of Victoria after an outbreak so large that it could not be fully eradicated from the area.

Left: A tree infected by giant pine scale. Right: The pest excretes a substance that looks like white cotton.Source: the Department of Primary Industries and Regions / Agriculture Victoria
Giant pine scale excretes a substance that looks like white cotton. Source: The Department of Primary Industries and Regions/Agriculture Victoria

Adelaide locals fuming over closed reserve

The community in the Tea Tree Gully Council, where Elliston Reserve is located, have been distressed over the reserve's closure — believing it was closed so it could be sold off.

One social media user commented on the Council's announcement, "Watching this space to see if this becomes an estate. Just saying." While another has replied, "My thoughts exactly..."

Tea Tree Gully Mayor Marijka Ryan told Adelaide Now the council has received "abusive emails by the dozen,” after closing the reserve. "We’re as devastated as the community but we can’t do anything about it," she continued.

Locals are urged to contact the Exotic Plant Pest Hotline on 1800 084 881 if they see, or suspect giant pine scale.

Love Australia's weird and wonderful environment? Get our new weekly newsletter showcasing the week’s best stories.

Banner reads 'What on Earth' with 'Subscribe to our new weekly newsletter' and a collage of images of australian natural wildlife.
Click here to sign up to our newsletter.