Yellowstone fires of 1988
The Yellowstone fires of 1988 together formed the largest wildfire in the recorded history of Yellowstone National Park in the United States. Starting as many smaller individual fires, the flames quickly spread out of control with increasing winds and drought and combined into one large conflagration, which burned for several months. The fires almost destroyed two major visitor destinations and, on September 8, 1988, the entire park was closed to all non-emergency personnel for the first time in its history. Only the arrival of cool and moist weather in the late autumn brought the fires to an end. A total of 793,880 acres (3,213 km2), or 36 percent of the park was affected by the wildfires.
Thousands of firefighters fought the fires, assisted by dozens of helicopters and fixed-wing aircraft which were used for water and fire retardant drops. At the peak of the effort, over 9,000 firefighters were assigned to the park. With fires raging throughout the Greater Yellowstone Ecosystem and other areas in the western United States, the staffing levels of the National Park Service and other land management agencies were inadequate for the situation; over 4,000 U.S. military personnel were soon brought in to assist in fire suppression efforts. The firefighting effort cost $120 million ($240 million in 2017). No firefighters died while fighting Yellowstone fires, though there were two fire-related deaths outside the park.
Before the late 1960s, fires were generally believed to be detrimental for parks and forests, and management policies were aimed at suppressing fires as quickly as possible. However, as the beneficial ecological role of fire became better understood in the decades before 1988, a policy was adopted of allowing natural fires to burn under controlled conditions, which proved highly successful in reducing the area lost annually to wildfires.
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