What are the two main parts of a wildfire?

The two main parts of a wildfire are commonly referred to as the head and heel. The head of the fire is the leading edge that spreads rapidly and is typically the most intense and destructive part of the wildfire. This area can produce large flames and severe heat as it consumes available fuel, usually moving in the direction of the wind. The heel refers to the back portion of the fire, which burns more slowly and generally with less intensity. Understanding these two parts is essential for fire behavior analysis and management strategies during wildfire incidents.

In contrast, the other terms refer to concepts that are not standard nomenclature used to describe the structure of wildfires, often relating to different aspects of fire behavior or propagation rather than distinct parts of the wildfire itself. For instance, the term 'crown' might refer to crown fires burning in the tops of trees, while 'base' is not a commonly used or defined term in wildfire terminology. Similarly, 'front and back' and 'tail and spread' do not represent established concepts within the context of wildfire parts, focusing instead on dynamics and behaviors that occur during a fire event.