The Pine Barrens was named for its sandy, acidic, nutrient-deficient soil. The pitch pine species that dominates the Pine Barrens has developed cones that open in response to intense heat, scattering seeds on the nutrient-rich ashes left by the fire. Another fire-adaptive characteristic is to drop lower branches, creating a canopy high enough to resist surface fires. Fire clears competing vegetation and brings in the sunlight that pines need.
The Pine Barrens is home to three main pine-dominated habitats. Pine-oak forest is the tallest, with a tree layer consisting of post oak and blackjack oak. The shortest forest type is the pygmy forest, a scrub species of pitch pine and blackjack oak, generally less than 10 feet tall. In between the tall and short extremes, the pine-shrub oak forest has pitch pines reaching heights of more than 30 feet.
Cedar and red maple swamps border drainage courses in the Pine Barrens. White cedar needs open, sunlit conditions for germination and growth; fire suppression may result in the displacement of white cedar by shade-tolerant red maple. The tannic acid present in Atlantic white cedar, iron in the streams and acidic waters contributed to the formation of a number of unique plant and animal communities. According to the New York Natural Heritage Program, the cedar swamps are the second rarest Pine Barrens ecological community in the state; the rarest is the dwarf pine plains.
Only about 10 percent of the original extent of the Pine Barrens remains as intact habitat. Changes in vegetation cover have an impact on habitat and the wildlife that depends on it. There are 850 species of plants found in the Pines, including the rare curly grass fern, and broom crowberry. Another special feature is range overlaps, where 109 southern plants and 14 northern plants reach their geographic limits.