Fire-Tolerant or Fire-Dependent? (Rock Creek Park)

Pitch pine (Pinus rigida) cones mature in two years. Many of them require fire to open and release their seeds.
Photographer: Flickr user sandy richard
Mature pitch pine can be found scattered near Boulder Bridge, on hilly areas in the north of the park, and at Fort Totten in the Coastal Plain, but juvenile pitch pine trees are harder to find in the Park. Pitch pine seedlings have difficulty getting established in the natural layer of "duff" (decayed leaves, pine needles, and other organic matter) that builds up on top of the mineral soil in the absence of wildfire. In the Coastal Plain, many pitch pine cones are serotinous, which means they stay tightly closed unless the heat of fire opens them; only then do they drop their enclosed seed onto the freshly groomed (burned!), sunlit forest floor.1 We can say that pitch pine is not only tolerant of fire, but somewhat dependent on fire for its species’ regeneration and long-term survival.