Forage crops, soybeans, and grain for dairy cattle occupy the largest acreage of cropland. Wooded areas, consisting mostly of farm woodlots, are extensive on the steepest parts of the area. Large centers of population and industry stimulate urbanization throughout the area. On some ridges and isolated peaks, however, elevation is as much as 500 m or more. The dissected part of the Piedmont Plateau is underlain mainly by granite, gneiss, and schist.
Basins are underlain by Triassic traprock, sandstone, shale, and conglomerate.
The sedimentary rocks contain numerous dikes and sills of diabase and basalt. Other local areas are underlain by limestone. Topography is mostly gently sloping or sloping. Steeper slopes are mostly on the ridges at higher elevations or on side slopes adjacent to drainageways. Average annual precipitation -900 to 1,150 mm.