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In many temperate and boreal forests, a century of aggressive fire suppression allowed dead branches, needles, and undergrowth to accumulate on the forest floor. This litter, once cleared periodically by small natural fires, now serves as continuous fuel that can carry flames into the tree canopy. Modern prevention programs have therefore shifted strategy: rather than extinguishing every ignition, land managers conduct controlled burns during cool, damp seasons to remove excess fuel before it can support a catastrophic wildfire. Firebreaks, cleared strips of land that deny flames a continuous fuel path, are also maintained along ridgelines. Officials note that these preventive burns are deliberately timed for low wind and high humidity, since a burn conducted under the wrong weather conditions could itself escape control.