University of Tasmania's Landmark Study on Forest Regrowth and Fire Risk

The University of Tasmania (UTAS) has delivered compelling evidence through a groundbreaking study that challenges long-standing debates in fire ecology. Researchers led by Professor David Bowman, a leading expert in pyrogeography and fire science, utilized a rare natural experiment to demonstrate how post-logging regrowth in Tasmania's wet eucalypt forests exhibits heightened flammability compared to mature old-growth stands. This research, published in Environmental Research Letters in early 2026, builds on decades of monitoring at UTAS's dedicated field sites and provides the first landscape-scale experimental proof of a theory first proposed nearly 60 years ago.

Tasmania's tall wet eucalypt forests, dominated by species like Eucalyptus regnans, are iconic ecosystems covering significant portions of the island state. These forests are prized for their biodiversity, carbon storage, and timber value, but they face intensifying pressures from climate change and land management practices. UTAS's Fire Ecology Research Group has been at the forefront of understanding how human interventions, such as commercial logging, alter fire regimes in these environments. The new findings underscore the university's pivotal role in advancing Australian higher education's contributions to environmental science and policy.

The 2019 Riveaux Road Fire: Nature's Perfect Laboratory

In January 2019, a lightning-ignited bushfire known as the Riveaux Road fire swept through a long-term UTAS research site in southern Tasmania. This event burned across a mosaic of old-growth wet eucalypt forest and adjacent 40-year-old regrowth from previous logging operations, creating an ideal 'before-and-after' comparison. Pre-fire data collected by the team included detailed measurements of fuel loads, canopy structure, and microclimates in both forest types. Post-fire assessments revealed stark differences: regrowth areas suffered significantly higher canopy scorch and tree mortality, with flames reaching greater heights due to denser lower canopies and drier conditions.

Specifically, the study quantified that regrowth forests had combustible dense understoreys and hotter, drier microclimates, facilitating more intense burning. Mature forests, characterized by tall canopies and moist rainforest understories, acted as firebreaks, limiting spread under moderate weather conditions. This direct evidence addresses previous limitations in fire research, where indirect methods like satellite imagery or fuel modeling often yielded inconclusive results.

Historical Context: Reviving Jackson's 1968 Theory

The research revives W.D. Jackson's influential 1968 theory, born from observations of Tasmania's catastrophic 1967 bushfires that nearly engulfed Hobart. Jackson posited that wet eucalypt regrowth enters a 20-50 year 'danger zone' post-disturbance, where dense sapling layers near the ground promote crown fires. UTAS scientists confirmed this through rigorous field data, noting that logging mimics severe wildfires by resetting forests to this flammable stage. Regeneration practices—slashing debris, burning slash, and aerial seeding—exacerbate the risk, placing one-fifth of Tasmania's tall wet forests in this vulnerable phase.

UTAS's commitment to paleoecology and long-term plot networks has enabled such historical linkages, positioning the university as a hub for interdisciplinary fire science in Australia. Collaborations with international partners further amplify these insights for global eucalypt-dominated systems.

UTAS Researchers Leading the Charge in Fire Ecology

Professor David Bowman's team at UTAS's School of Natural Sciences includes experts like Grant Williamson (remote sensing specialist), Lynda Prior (stand dynamics), and international collaborators from the University of New South Wales and Australian National University. Bowman's FireLab facility, a state-of-the-art flammability testing lab, supports experimental validation of field observations. This study exemplifies UTAS's strength in applied environmental research, funded by the Australian Research Council and Tasmanian government grants.

The university's researchers emphasize that while the 2019 fire was moderate, climate-amplified extreme weather could overwhelm mature forest buffers, highlighting the need for advanced modeling and predictive tools developed at UTAS.

Implications for Tasmanian Forest Management and Biodiversity

Tasmania's native forest logging industry supplies high-value timber, but the study warns that ongoing clearfelling creates expansive flammable regrowth landscapes. With climate projections forecasting hotter, drier conditions, repeated fires in young stands could convert forests to shrubby sedgelands, eroding biodiversity hotspots. UTAS ecologists note that old-growth forests store more carbon and support unique rainforest understories, making preservation critical for climate resilience.

Photo by Matt Palmer on Unsplash

• Regrowth: Higher fuel continuity from ground to canopy.
• Mature forests: Moist understories suppress fire spread.
• Policy shift: Prioritize selective logging or reserves to minimize regrowth patches.

Australian-Wide Echoes: Insights from ANU and Beyond

David Lindenmayer from the Australian National University (ANU) has published meta-analyses showing logging elevates high-severity fire probability across southeastern Australia, aligning with UTAS findings. A 2020 UTAS study on the same fire using satellite data reported 60% canopy death in regrowth versus 12% in old-growth. These multi-university efforts underscore higher education's role in informing national bushfire policy amid Black Summer legacies.Read the full UTAS study here.

The Debate: Forestry Perspectives and Methodological Critiques

Not all experts agree. Foresters like Robert Onfray argue that logged areas represent <0.1% of forests annually, with weather and topography as primary drivers. The Australian Forestry Association cites studies (e.g., Attiwill et al. 2014) showing no landscape-scale increase in fire severity from harvesting, and prescribed burning/thinning reduces fuels. They critique regrowth claims as conflating wildfire regrowth (dominant post-Black Summer) with logging effects, noting retracted UTAS papers due to errors. UTAS counters that even small regrowth patches intensify local fires, with natural experiments providing robust evidence.

This scholarly debate highlights Australian universities' vibrant discourse in forest science, fostering evidence-based management.

Climate Change Amplifies the Risks

Projections from UTAS climate models indicate more frequent extreme fire weather, potentially overwhelming mature forest buffers. Regrowth's drier microclimates—2-3°C hotter, 10-20% drier—exacerbate this. Collaborative research with CSIRO emphasizes integrating fire ecology into adaptation strategies, positioning UTAS as a leader in interdisciplinary higher education responses to global change.

Future Directions: Research and Policy at Australian Universities

UTAS calls for trials on regrowth fuel reduction beyond commercial thinning, which leaves slash fuels. ANU and UTAS advocate zoning to protect buffers around communities. Higher education institutions are pivotal, training fire ecologists via programs like UTAS's Master of Protected Area Governance. Explore research positions in this field.

Stakeholder Views: Environment, Industry, and Government

Environmental groups hail the study as proof to end native logging; industry stresses sustainable practices and economic contributions (timber jobs). Tasmania's government balances conservation with forestry, funding UTAS research. Multi-perspective dialogues at university forums drive constructive solutions.

Photo by Matt Palmer on Unsplash

Opportunities in Higher Education and Careers

This research opens doors for PhD candidates in fire ecology at UTAS and ANU. Australia's universities offer scholarships for climate-fire studies, preparing graduates for roles in policy, modeling, and management. Check Australian university jobs for openings.