Pygmy Pine Plains
The Pgymy Pine Plains (or Dwarf Plains) of the Pine Barrens of New Jersey are upland forests that have long intrigued biologists.
A sandy road cuts across a pygmy pine forest. © Mark Schoneveld
Early in the 20th Century, Witmer Stone described them as “desolate stretches of white sand barrens … for the most part devoid of trees higher than one’s knees.” The Pine Plains are dominated by dwarfed Pitch Pines and Blackjack Oaks in the low canopy. Pine Barrens Heather is frequent in the understory. Ground cover includes lichens, mosses, and the sub-shrubs Bearberry and Teaberry.
All of the tree species in the Pine Plains are also found throughout the Pine Barrens, so why do they take on a dwarf form in the Plains? Though the mechanisms are not entirely understood, most experts believe that a combination of factors are involved. The Pine Plains soils are particularly droughty and nutrient-poor, and, as plateaus elevated above their surroundings, the plains are subject to higher winds. Most importantly, for centuries these forests have been exposed to wildfires at least twice as frequently as other Pine Barrens forests. These extremely harsh conditions have created a forest with Pitch Pine trees that are stunted and have adopted certain genetic peculiarities. The pines of the Plains almost exclusively produce “serotinous” cones - cones that open only when subjected to the heat of wildfire - and have an extraordinary ability to send up new growth from their roots, even when the rest of the tree is completely burned.