The fire ecology of Johnson County is variable, depending upon the diverse plant communities that reach from the Big Horn Mountains to the Powder River basin. Most plants in the area are adapted to fire and re-establish themselves by seed or re-sprouting. Chokecherries, aspen, and most grasses typically re-sprout after fire whereas Curl-Leaf Mountain Mahogany and Wyoming Big Sagebrush reestablish themselves by seed. Some trees like Ponderosa Pine are resistant to surface fire and survive the low flames. The Lodgepole Pine forests require canopy fires to create favorable conditions for new seedlings as the heat opens the closed pinecones and releases their seeds.
A number of plant species require fire or other disturbances to maintain structure and function while others require long undisturbed periods of time to fully develop. Seasonal weather systems and lightning from summer thunderstorms contribute to these fire cycles and burn patterns in northeastern Wyoming.
At various places around Johnson County you can see burn patterns where fires have occurred. This is most easily seen along the eastern slopes of the Bighorn Mountains where some patches of forest look shorter or younger than the surrounding forest. Some patches are so young that grasses and shrubs have re-sprouted and dominate the landscape.