From 1972, the National Park Service began allowing natural fires in Yellowstone to burn under controlled conditions. Fires of this type were referred to as prescribed natural fires. Between 1972 and 1987, a total of 235 prescribed natural fires burned a relatively small 33,759 acres (137 km2) under the directives of the new policy. Of these, only 15 spread to more than 100 acres (0.4 km2). The five years prior to 1988 were much wetter than normal and this may have reduced the area of the fires during that period. The prescribed natural fire policy appeared to be an effective way to manage fires, especially in the Yellowstone region.
From 1972, the National Park Service began allowing natural fires in Yellowstone to burn under controlled conditions. Fires of this type were referred to as prescribed natural fires. Between 1972 and 1987, a total of 235 prescribed natural fires burned a relatively small 33,759 acres (137 km2) under the directives of the new policy. Of these, only 15 spread to more than 100 acres (0.4 km2). The five years prior to 1988 were much wetter than normal and this may have reduced the area of the fires during that period. The prescribed natural fire policy appeared to be an effective way to manage fires, especially in the Yellowstone region.
制定的自然山火可以在哪個公園使用？
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