The eucalyptus trees in this photo owe their very existence to fire. Rainforest is largely confined to moist gulleys. But as in the last few decades where bushfires are not let to burn, the rainforest is slowly creeping out of the gulleys. Rainforest species prevent young eucalyptus trees from growing by blocking sunlight. Rainforest flora is largely non-fire resistant.
Eucalypts are fire tolerant.
A bushfire kills off the advancing rainforest species, allowing light to the forest floor, the young eucalypts grow quickly in the new light, by the time rainforest species start advancing again the young eucalypts hopefully are above canopy level, and so the cycle goes on. Bushfires are that much a part of Australian climate that many tree species such as the Eucalyptus are fire resistant, others such as some of the Banksias actually require fire to open seed pods. In New South Wales the most fire prone areas are the coastal forests, the tablelands and Great Divide. The Sydney region has had its share of fires. As recently as January 1994 saw out of control bushfires in the Sydney area, many homes were lost.