If a fire ring is already established at your site, make every effort to use it. It takes years for the forest to cover the scars left by even the smallest fires. Always keep this in mind when building a fire. Never use rocks that hold moisture, from a river bank or lake shore, for a fire ring. Once heated, the expanding moisture will cause them to explode, this is very dangerous.
Fires deplete a resource, wood, that can be a necessity in an emergency situation.
Fires are also difficult for cooking often being quite messy, time consuming, and unreliable. Wet wood fires offer no constant temperature or simmering potential, and can be terribly frustrating. To build a fire, start with dry twigs and small sticks, pencil to finger size in diameter. Use tinder, leaves, pine needles, or bark to ignite the kindling. Add larger sticks as the fire builds up.