Visual Fuel Hazard Assessment in Eucalyptus salubris Woodlands Across Time Since Fire Chronosequence, Great Western Woodlands SuperSite, 2012

Understanding fire behaviour and vegetation flammability is important for predicting the consequences of fires. Visual assessments of fuel, such as those developed in Project Vesta, have been widely applied to facilitate rapid data acquisition to support fire behaviour models. However, the accuracy and potential wider application to other plant communities of Vesta visual fuel assessments has received limited attention. The Great Western Woodlands (GWW) region of south-western Australia supports the world’s largest remaining area of Mediterranean-climate woodland, which in mosaic with mallee, shrublands and salt lakes cover an area of 160 000 km2. Eucalyptus woodlands in this region are typically fire-sensitive, and fire return intervals recorded over recent decades have been much shorter than the long-term average. This has led to considerable conservation concern regarding the loss of mature woodlands, and has highlighted a need to better understand how fuel and vegetation flammability changes with time since fire. We visually assessed fuels using Vesta methods across 24 sites in a multi-century (10 to 260+ years since fire) time-since-fire sequence derived from growth ring-size relationships in fire-sensitive Eucalyptus salubris (gimlet) woodlands.