Indices of fire characteristics in sandstone heath near Sydney, Australia

The relative sensitivity and performance of post-hoc indices of fire charac teristics were examined in a heathland area burnt in 1994. Sites burnt at d iffering times before 1994 were selected and qualitatively allocated to cla sses of high and low crown damage. Subsequent measures were made of height of consumption of crowns, length of the dead portion of Xanthorrhoea resini fera leaves, and minimum tip diameters of burnt branches of the shrubs, Ban ksia oblongifolia and Banksia ericifolia. Results indicated that significan t differences in mean, minimum tip diameter corresponded to contrasting cla sses of crown damage (larger mean tip diameters in high crown damage sites) . Mean minimum branch tip diameter in B. oblongifolia was not significantly correlated with fuel age but significant correlations were found with esti mates of rate of spread and Byram fire intensity at the study sites. The mi nimum branch tip diameter method has potential for further development and use as an indicator of fire intensity in heathland vegetation.