Kaitlyn L. Hammond, Craig R. Nitschke, Raphaël Trouvé and Patrick J. Baker, Forest Science, 1 July 2026
New long-term research from the University of Melbourne shows that carefully designed tree removal can help remaining trees grow larger, maintain carbon storage and support wildlife. The researchers compared different levels of tree removal with unharvested areas in largely even-aged mountain ash regrowth at Tanjil Bren.
After approximately 30 years, the heavily thinned areas had the largest trees. The researchers report that these trees were around 20% greater in diameter than those in the unharvested areas. The retained stands had also recovered the biomass removed and most of the additional growth recorded in the controls. Larger mountain ash are more likely to form hollows and less likely to be killed by low- to moderate-intensity fire.
Disturbance also allowed Acacia, an essential food and movement resource for Leadbeater’s possum, to regenerate. Acacia had disappeared from the unharvested areas, which the academic paper found were no longer suitable Leadbeater’s possum habitat. The researchers found the possums in every treated area surveyed, including clearfelled areas, and none in the unharvested areas.
This research matters for forest restoration. Rules that assume tree removal is inherently harmful risk excluding tools that can restore large trees, forest structure and wildlife habitat. Active management should be carefully designed, evidence-based and matched to the condition of each forest.
- Read the peer-reviewed research, ‘Alternative Silvicultural Systems Maintain Multiple Values in Tall Eucalypt Forest’, in Forest Science.
- Read in the researchers’ overview, ‘We revisited a forest experiment that lay forgotten for 30 years. What we found was astounding’, in The Conversation.
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