The Zaca fire began on July 4, 2007, deep in the Santa Ynez Mountains, when a rancher accidentally ignited dry brush with sparks from a metal grinder. Firefighters arrived quickly but the fire had already spread up the steep canyon into the difficult terrain of Zaca Ridge. Over the next few days the fire spread rapidly into Los Padres National Forest and the San Rafael Wilderness.
The wildfire was primarily driven by a heavy buildup of fuel that had not burned in many years. The dry and dense chaparral filling the region was so easily combustible that it often seemed to explode into flames upon contact with sparks or embers. These fuel-driven fires can move quickly and unpredictably with scorching hot temperatures, making ground fighting very dangerous. This and the fact that the region has little to no road access meant that firefighters were mostly restricted to aerial attacks. Luckily, the fire burned primarily in uninhabited wilderness, so containment strategy was focused on not letting it move south toward Santa Barbara and Ventura.
While the efforts to keep the fire in the backcountry were ultimately successful, the 240,000-acre fire took three months to contain at a cost of $118 million. No homes burned. Structure damages were limited to a single Forest Service outpost and a helicopter that crashed during takeoff from Figueroa Mountain.