In 2006, it was the third largest wildfire in California history. The fire started on Labor Day, September 4, 2006 and by October 1 had burned over 162,700 acres (658 km2), cost US$70.3 million, and at one point had 4,600 active firefighters. It was completely contained on October 13.
The Day Fire burned approximately 162,702 acres of both National Forest (97.4%) and privately owned lands. The fire started on the Ojai Ranger District, in the Congressionally Designated Wilderness known as the Sespe Wilderness, in Ventura County. The Sespe Wilderness is under the Federal jurisdiction of the United States Forest Service. 1,943 acres of private land was burned in Lockwood Valley and the Mutau Flat area. A total of eleven structures were reported destroyed including one residence and ten outbuildings; 1 modular home, 1 small cabin, 3 outbuildings, 2 barns, 3 trailers and 1 unknown. In addition there were four damaged buildings; including, one damaged residence and three damaged outbuildings.
The Day Fire was determined to be human caused. Specifically, a debris burn consisting of clothing, ammunition and other items were illegally ignited during fire restrictions. Ignited material coming out of the debris burn came in contact with surrounding dry grasses, causing a wildland fire to occur. On September 7, 2006, Steven Butcher walked out of the Day Fire with burns to his face. Butcher’s statements to responding officials and Forest Service investigators place him at scene when the fire initially started. Additionally, Butcher’s statements describe how the fire first burned. Those statements closely resemble where Forest Service fire investigators placed the fire origin and how the fire initially spread. Steven Butcher subsequently went to trial, was found guilty in Federal Court and sentenced to serve six years in Federal detention.