Depending on the environmental conditions , and the relative effectiveness of a given firebreak , firebreaks often have to be backed up with other firefighting efforts . Even then , it is still sometimes possible for fire to spread across a seemingly impenetrable divide . During the worst part of the fire season in southern California , strong Santa Ana winds were observed to blow carpets of burning embers across eight-lane freeways . During the 1988 fires in Yellowstone National Park , hot embers managed to cross the Lewis Canyon , a natural canyon up to a mile wide and 600 feet ( 180 m ) deep . In Australia , firebreaks are less effective against eucalyptus forest fires , since intense fires in tinder-dry eucalyptus forest spread through flying embers , which can be carried by the winds to trigger new blazes several kilometres away
1988 fires
Yellowstone fires of 1988
Firebreak