McPhee opens The Pine Barrens with one of the descriptive techniques he use. He gives a detailed physical description. The opening perspective for this description is from atop the Bear Swamp Hill fire tower in Washington Township. He gives a panoramic eagle's-eye view of the vast expanse of Pine Barren. He adds that the view is virtually the same from the neighboring fire tower at Apple Pie Hill. He remarks on several distinguishing features that break up the scene of pines and some oaks in the Barren. There are the Atlantic white cedars that extend above the pines and grow along the twists of rivers within the Pine Barren. There is the dwarf forest where a person "can stand among the trees and see for miles over their uppermost branches." There is the view to the south where the "view is twice broken slightly--by a lake and a cranberry bog--but otherwise ... to the horizon in forest."
After the physical detail, McPhee switches to describing the Barrens in terms of history; this includes present history and distant history. He describes how developments presently encroach at the borders of the Barren and create small inlets of city life in the edges of the quiet wilderness of the forest. He describes how New Jersey had plans (now realized) for expanding its high-speed roadway system and accompanying the New Jersey Turnpike with half a dozen other north-south turnpikes. He further describes the Barrens in terms of recent history by comparing population per square mile giving New Jersey's as at least 1,000 and the Pine Barren's as about 15 people per square mile. The distant history reveals that it came by its name when the original settlers judged the forests to be so dense and unfavorable to farming that they left them intact and began to refer to that land as "barren," leading to the Pine Barrens.
Settlers ... found these soils unproductive for farming , left the land uncleared, and began to refer to the region as the Pine Barrens.
The mention the people per square mile leads to another more complicated descriptive technique in which he describes the Barrens in relation to the people who live there in what some call "a suburb":
the heart of the pine country is ... Hog Wallow. ... [with] twenty-five people ... [who] describe it, without any apparent intention to be clever, as a suburb of Jenkins, a town three miles away, [with] forty-five people.
One of these people, through whose eyes McPhee describes Pine Barrens, is Frederick Chambers Brown. He lives up a dirt road "at the edge of a wide cranberry bog" and gave McPhee a drink of water from his front yard pump and a tour of his home and his life in Pine Barrens. These are some of the techniques McPhee uses to describe the Pine Barrens, which includes its 15 people per square mile.