The main entrance to Woodfield is located off the old Great Road across from Tenacre Foundation; a gravel drive leads to a small parking lot. A hiking trail leading into the Reservation begins here. A second entrance to the Reservation is a footpath from the south side of Drakes Corner Road. Both entrances are marked by signs.
Woodfield Reservation is an irregularly shaped tract of almost 100 acres. It is a prime illustration of undisturbed land of Princeton Ridge, which has been called an "island of forest" in a "sea of suburban and agricultural development." The Reservation is covered with a mature forest and has many fairly steep slopes, making it suitable for vigorous walkers. Two of the most interesting features of Woodfield are Council Rock, which overlooks a large, heavily bouldered basin, and Tent Rock, a massive boulder.
About half of the land is owned by Princeton Township. The remaining half of the Reservation was made available for public use in 1964 by Mrs. John P. Poe. At this writing, negotiations are in progress to add this tract to the public domain. Under a 1992 agreement between the Princeton Regional Planning Board and developers of Rushbrook, seven additional acres, including Tent Rock, have been designated for inclusion in Woodfield. New access trails into the Reservation from Rushbrook will also be added.
Geology and Topography
The Reservation lies along the steep south slope of Princeton's diabase ridge, an area of igneous rock formed more than 150 million years ago by volcanic intrusion of basalt, or "diabase," rocks into a region of bedded shales. The slopes feature stony soils, extensive fields of large boulders, and outcrops of the diabase, which is medium to light gray when weathered, and darker on a fresh surface. Individual crystals can easily be seen in the rock. The outcrops have fractures perpendicular to each other, probably from shrinking while cooling. Contrary to popular local myth, these boulders were not deposited by glaciers (which did not extend this far south). They are "home grown," the result of 180 million years of weathering and erosion of the rock originally located here.
Woodfield's high wetland areas drain into several stream corridors and two chains of ponds that, in turn, feed into Stony Brook. The water table here is quite unusual, because both the diabase and shale rocks not only form boulder fields into which water drains easily, but also weather to a fine and nearly impervious clay. Soils that overlay accumulations of clay drain very poorly and are wet much of the time; soils that overlay stony subsoil drain quickly and are generally dry. This patchy pattern of natural drainage produces a mosaic of seasonally swampy and dry upland forest.
Woodfield contains many mature hardwoods, including large tulip poplar, beech, oak, and hickory. In most areas there is a full understory of shrubs, ferns, and wildflowers. The first leaves of spring at the confluence of the two streams in the center of the Reservation are a sight not to be missed.
The woods are home to a wide range of birds, among them the rarely seen pileated woodpecker. Summer residents include scarlet tanagers, rose-breasted grosbeaks, Northern orioles, and numerous warblers. The woods are a welcome stopover point for these and other migratory species in spring and fall. It is the only woodland tract where serious birders can spot the Louisiana water thrush. Many deer and small animals, such as raccoons and opossums, make their homes here.
Signs at the entrances carry a map of the trails and include prohibitions against horseback riding, use of motorized vehicles, and injury of animal or plant life.