Spatial variability of experimental fires in south‐west Western Australia

Descriptions of fire behaviour and severity are often limited to single measures of intensiv and some assessment of spread rates. This study examined the small‐scale variability in fire severity during three prescribed fires in shrub and woodland communities in south‐west Western Australia. Using Thermocolor pyrometers, the temperatures reached during the fires were found to vary spatially, because of variation in fuel distribution and type. Different shrub species also reached different temperatures during ignition. Temperatures at and just below the soil surface also varied greatly. Only in a very intense fire caused by heavy fuel loads was a uniform fire treatment experienced. Such fire variability may be important in determining post‐fire vegetation response, especially where temperature‐dependent germination or coneopening occurs. In fire studies some estimate of fire variability should be obtained to allow adequate explanation of subsequent regeneration patterns.