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.

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; more than 4,000 U.S. military personnel were soon brought in to assist in wildfire suppression efforts.

In the eastern United States, with its significant rainfall, wildfires are relatively small and have rarely posed a great risk to life and property.

[3] The worst loss of life in United States history due to a wildfire occurred in 1871 when the Peshtigo Fire swept through Wisconsin, killing more than 1,200 people.

[11][12] The Great Fire of 1910 burned 3,000,000 acres (12,000 km2), destroyed a number of communities, and killed 86 people; this event prompted various land management agencies to emphasize wildfire suppression.

[19] However, some researchers in the 20th century argued that this policy should be changed, on the grounds that wildfires clean out the understory and dead plant matter, allowing economically important tree species to grow with less competition for nutrients.

Native Americans would often burn woodlands to reduce overgrowth and increase grasslands for large prey animals such as bison and elk.

[20][21] As early as 1924, environmentalist Aldo Leopold argued that wildfires were beneficial to ecosystems, and were necessary for the natural propagation of numerous tree and plant species.

[26] In Yellowstone, a very short growing season due to high altitude and relatively poor soils allows the lodgepole pine to reach ages approaching three hundred years before other trees such as Engelmann spruce and subalpine fir become established.

[26] The lodgepole pines found throughout the Yellowstone Plateau high country grow in uninterrupted dense stands averaging similar ages in various groupings.

[30] In the northwest, the Fan Fire started on June 25, and was originally considered a threat to the town of Gardiner, Montana, just outside the park's north entrance.

The fire started on July 22, when a man cutting timber dropped his cigarette in Caribou-Targhee National Forest just outside the park's western border.

The fire continued its eastward advance along the Yellowstone Plateau, and on August 25, reached visitor facilities at Canyon, where land management agencies and the U.S. military put forth enormous efforts to protect structures.

[30] There, private citizens assisted assigned personnel in soaking hundreds of acres of forestland to protect both the town and an electrical power substation.

[35] Between September 5 and 7, a dry front pushed flames along the southern section of the North Fork Fire towards the large Old Faithful visitor complex adjacent to the Upper Geyser Basin.

[30] All non-emergency personnel were ordered to be evacuated; however, political issues influenced National Park Service management directives and the complex was not completely closed to incoming tourists, with some visitors still arriving at Old Faithful not long before the intense fire hit by mid-afternoon.

The night of the 9th and the morning of September 10, the North Fork Fire jumped a fireline along its northeastern flank and approached Mammoth Hot Springs where a large concentration of historic structures as well as the Park Headquarters is located.

[1] Some other fires were too remote or in too steep terrain for the safe operation of heavy equipment, and bulldozers were prohibited from many areas because of the impact they have on surface features.

[40] Later analysis has shown that, aside from concentrated fire suppression efforts near major tourist facilities, the firefighting work failed to stop what was likely an unstoppable force.

[42] In regions that did experience complete burnouts, the average depth of charred soil was only about half an inch (14 mm), so few roots, even grasses, were killed by the fire.

[44] The predominant tree in Yellowstone, the lodgepole pine, fared poorly from the fires, except in areas where the heat and flames were very mild.

[46] Contrary to media reports and speculation at the time, the fires killed very few park animals — surveys indicated that only about 345 elk (of an estimated 40,000–50,000), 36 mule deer, 12 moose, 6 black bears, and 9 bison had perished.

[49] Rodents likely experienced the highest mortality of all mammals due not only to heat and smoke they could not easily escape, but also because of the reduction in forest cover, allowing would-be predators less difficulty in spotting them.

There, monitoring stations maintained by the Montana Department of Health and Environmental Sciences and the park recorded 19 days where recommended allowable particulate concentrations were exceeded.

The more than a million gallons of diammonium phosphate-based fire-retardant material polluted some streams, but this too was transient and had no long term ill effects on water quality.

[37] However, fires did a lot of damage to 23 out of 61 picnic areas and campgrounds, 73 hiking bridges, 10 miles (16 km) of power lines and 300 utility poles.

[37] Major tourist locations in the park such as the one at Old Faithful were heavily staffed by fire fighting crews and equipment, especially at times of immediate danger.

On the same day, The Washington Post associated the smoke and presence of military vehicles and helicopters overhead with the 1968 events in Da Nang, Vietnam, giving the impression of catastrophe.

[29] When this optimistic announcement was followed by Black Saturday on August 20, and the fire that threatened the Old Faithful complex in early September, the media were again highly critical of the park service and its policies.

According to the 2004 plan, natural wildfires are allowed to burn, so long as parameters regarding fire size, weather, and potential danger are not exceeded.