Fire Regimes
Brown and Smith (2000) described four different types of fire regimes. The severity of the fire is crucial for managers to understand the survival and structure of the dominant vegetation. The four classifications based on severity are listed below.
Forests and Woodlands
Understory Fire: fires are usually non-lethal to the dominant vegetation and do not change the structure of the dominant vegetation. It is usually a low intensity surface fire.
Mixed severity fire: the fire causes selective mortality in the dominant vegetation, dependent on type of tree, or it can vary between understory and stand replacement.
Forest, Woodlands, Shrublands and Grasslands
Stand replacement: fire kills the above ground parts of the dominant vegetation and changes the structure substantially by 80 percent or more.
Non-fire regime: little or no occurrence of natural fire. This is considered to be a wet environment.
Land managers are using fire as a tool to begin restoring a natural fire regime in areas where fire suppression has been the practice. Ecosystems where fire has been suppressed, often requires several fires to restore a natural balance.

