On National Tree Day, researchers from the ARC Training Centre for Bioplastics and Biocomposites joined the national conversation on sustainable revegetation, showcasing a biodegradable tree guard designed to eliminate plastic waste from restoration projects.

Each year, over 70 million trees are planted across Australia, often protected by plastic tree guards. While effective in shielding young saplings, these guards can leave behind tonnes of microplastic pollution in creeks and oceans—especially after flooding and extreme weather events.

In response, researchers from the School of Chemical Engineering at The University of Queensland, including Centre researcher Clement Chan, have developed a biodegradable tree guard made from polyhydroxyalkanoates (PHAs)—a bacteria-produced biopolymer—and wood sawdust. This innovative material offers strength, toughness, and water resistance, while remaining fully biodegradable in natural environments.

“There’s growing industry demand for biodegradable alternatives that actually work in the field, and this prototype is a promising step toward practical, sustainable revegetation,” said Dave Madden, Restoration Project Manager at Queensland Trust for Nature (QTFN).

The tree guard was co-developed with QTFN through the Koala Habitat Restoration Partnership Program (KHRPP), ensuring it meets real-world revegetation needs. Unlike cardboard alternatives that collapse when wet, this prototype maintains its structure and performance, reducing the need for retrieval and preventing long-term plastic pollution.

Highlights:

  • ✅ Bio-based and biodegradable
  • ✅ Water-resistant and field-tested
  • ✅ Eliminates persistent microplastics
  • ✅ Reduces costs by removing retrieval
  • ✅ Strengthens research–industry collaboration

Centre researcher Clement Chan spoke about the innovation on Brisbane’s 4BC radio at 4:01pm on National Tree Day, sharing how bioplastics can support habitat restoration and koala conservation.

Listen here start @1:01: FULL SHOW: listen back to 4BC Drive with Gary Hardgrave, Friday July 25th, 2025 – 4BC – 4BC – Brisbane’s Premier News and talk radio station.

Let’s grow a more sustainable future—starting with smarter solutions.

Image 1: Carboard tree guard getting soggy and collapsing during use.  Image 2: Biodegradable tree guard prototype developed by UQ in collaboration with QTFN.