Fire modelling in Tasmanian buttongrass moorlands. IV - Sustaining versus non-sustaining fires

Buttongrass moorlands are widespread in western Tasmania. In these moorland s, the ability to conduct burning without having to rely on hard fuel bound aries (e.g. vegetation which is too wet to burn, water courses, mineral ear th breaks and/or roads) would be a major advantage to land managers, Such b urning relies on fires self-extinguishing and is normally referred to as un bounded burning. The aim of this project was to model the probability of fi res extinguishing using the data from 156 buttongrass moorland fires. The v ariables used were wind speed, dead fuel moisture and site productivity. Th e model, derived from a combination of logistic regression and classificati on tree modelling, predicts that fires will self-extinguish over a wide ran ge of conditions in low productivity moorlands but, in medium productivity moorlands, the conditions within which fires will self-extinguish will be m uch more restrictive. As a result, the technique of unbounded burning shoul d be widely applicable in low productivity moorlands, but will be of margin al utility in medium productivity moorlands.