In
Australia, we use this term for a fire that tears through the
bush, usually fueled by hot summer winds.
Bushfires are a natural part of the Australian environment and in the past would have been started mostly by lightning. The flora has evolved to adapt very well and many native trees have thick bark that burns easily, but protects the trunk underneath. The aftermath of a bushfire is often quite spectacular with fresh green shoots exploding out of the charred remains of the undergrowth.
However, since the arrival of humans and their fire creation, bushfire frequency has increased rapidly and it is not unusual to go through summer without there being at least one burning every day. Many of these will have been accidental, usually through stupidity - untendered camp fires, cigarette butts, etc. Occasionally they will have been deliberately lit - supposedly just for fun.
Bushfires destroy thousands of hectares of forest each year in Australia. They also cause millions of dollars worth of damage and sometimes lives are lost.
The Country Fire Authority are a group of volunteers that serve as the firefighters of the bush. They are usually made up of people that live near the area that they work in and they save thousands of sqaure kilometres of bush each year.
Bushfires are bad. Respect them and be prepared for them.