Since muck fires occur below ground level, the state of Florida is not able to officially track the number of such fires annually. The blazes are triggered when loosely packed organic material or "muck" below the top soil ignites, most commonly from wildfires and lightning strikes.
Since muck fires may thrive underground weeks after fires appear to be extinguished, the ground must be thoroughly soaked for them to be eliminated. Reaching temperatures up to 500 degrees, embers spreading sideways often cause additional ground fires great distances away. The underground burning also weakens tree roots and destabilizes the ground above, making it difficult for firefighters to bring equipment near fires due to soft ground and the risk of falling trees.