Fuel The substance that is ignited and burned during the process of combustion is called a fuel. Trees and other vegetation are fuels for wildland fires. This process is called photosynthesis . There are two main steps to photosynthesis. First, plants trap the sun's light energy in a compound called chlorophyll.
Energy is released in the form of heat and light.
This process is called combustion . A similar process occurs inside plants and animals. It is called respiration . During this process, carbon dioxide is released to the atmosphere. In other words, flamability is how easily a fuel ignites and how quickly the flames spread to nearby fuel.