Tree species response to prescribed burns in rehabilitated bauxite mines in Western Australia

Abstract

The response of fourteen tree species to autumn and spring prescribed burns was assessed in 11 to 13-year-old rehabilitated bauxite mines. Of the 578 trees recorded, 2.8% were killed, a further 14.7% resprouted basally (no resprouts above 2 m) while the remainder resprouted aerially (73.2%) or were not scorched (8.5%). This is indicative of the high tolerance to fire of all species recorded in this study. The most fire tolerant species were Eucalyptus calophylla, E. patens, E. botryiodes and E. maculata. The most susceptible species were E. accedens and E. wandoo. Increased fire tolerance was related to increased bark thickness and larger stem diameter. Rough-barked species were more resistant to fire than smooth-barked species. Tree mortality and the incidence of basal resprouting was higher following autumn burning than spring burning. Based on these findings, it would appear that spring burns are more favourable than autumn burns to the survival and growth of tree species in rehabilitated areas.