As of September 21, 2016, fires have burned over 62,000 acres of Yellowstone National Park, the highest number of acres since the 1988 fire season.
For comparison, the 1988 fires burned approximately 800,000 acres of Yellowstone National Park.
According to a Yellowstone press release, 22 fires sparked in Yellowstone National Park, with four still active: Maple, Buffalo, Fawn, and Central Fires. One fire (Boundary Fire) was suppressed at 192 acres. The remaining 17 burned a collective 14.8 acres. The majority of Yellowstone’s burn acreage came from Maple Fire, which has burned over 45,000 acres so far. From a Yellowstone press release:
The park protects human life and developed areas (e.g., roads, buildings, and other infrastructure) from the threat of wildfire. At the same time, fire is allowed to carry out its ecological role on the landscape as much as possible. This season, 11 fires were immediately suppressed because values were at risk. Seven fires were the result of human activity such as campfires not being put out, vehicle operations, or improper cigarette disposal. Fifteen fires were caused by lightning strikes.
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As fall approaches and brings with it cooler temperatures, shorter days, and some recent precipitation, fire activity slows. Concentrations of down trees in some of these fire areas will burn until snow blankets the Yellowstone plateau. Visitors will see smoke rising within burned areas from time-to-time as wind and warmer weather pass over the area. This will occur until enough moisture accumulates to extinguish the hot spots.
Since 1988, the number of fires in Yellowstone National Park has ranged from one to 78 in a given year. As seen this year, lightning is the major cause of fires within the park. In an average year, the park will see 26 lightning-caused fires. Human-caused fires are still a significant contributor to the fire history within the park.
The public hears much about the large fires that occur in Yellowstone, yet, 75 percent do not reach more than 0.25 acres in size. About 92 percent never burn more than 100 acres. These fires occur in areas where fuel conditions and topography limit the fire’s growth or they go out on their own due to weather. Another factor in keeping the average size of fires low is the quick response by the park’s fire crews to suppress any human-caused fire.
Fire plays a central role in Yellowstone’s ecosystem by burning away old growth, renewing habitat by redistributing nutrients in the soil. In addition, Yellowstone’s lodgepole pine population requires fire in order to spread seeds, in a process known as pyriscence. When enough heat melts the resin of a lodgepole pine cone, the seeds burst forth, ready, in time, to take their parents’ place in the forest.