Wildfire 山火
A wildfire or wildland fire is an uncontrolled fire in an area of combustible vegetation that occurs in the countryside area. Depending on the type of vegetation that is burned, a wildfire can also be classified as a brush fire, bush fire, forest fire, desert fire, grass fire, hill fire, peat fire, vegetation fire, or veld fire. A wildfire differs from other fires by its extensive size, the speed at which it can spread out from its original source, its potential to change direction unexpectedly, and its ability to jump gaps such as roads, rivers and fire breaks. Wildfires are characterized in terms of the cause of ignition, their physical properties such as speed of propagation, the combustible material present, and the effect of weather on the fire.