What is a firebreak or fireguard?

This is some type of break or barrier on the boundary of the burn unit that aids in containing the fire. Firebreaks delineate the boundary of the burn unit, allow for vehicle access around the unit and reduce the intensity of the fire along the edge. Firebreaks can be mowed lines, bareground lines made by dozing, grading or discing, or natural barriers such as creeks, cultivated fields, vegetation changes or roads.