Fires have always occurred periodically in the Yellowstone ecosystem. Records kept since 1930 show that lightning starts an average of 22 fires each year. Vegetation in the Greater Yellowstone Ecosystem has adapted to fire and in some cases is dependent on the removal of the forest overstory to become established. Other plants growing on the forest floor are adapted to survive at a subsistence level for long periods of time until fires open the overstory.

Wildland Fire in Yellowstone