Physical Geography

New Jersey occupies part of two physical regions of the United States, the Atlantic Coastal Plain and the Appalachian Highlands. The state lies within three sections of the Appalachian Highlands—the Piedmont; the Highlands, the southernmost extension of the New England Upland; and the Ridge and Valley.

The Coastal Plain is a generally flat to rolling area south of a line connecting Trenton and Perth Amboy. Roughly three-fifths of New Jersey lies in this region. The inner part of the Coastal Plain is a fertile area of truck farms, dairy farms, and orchards; the rest (the seaward section), with soil made up of loosely consoliated sands, is of low fertility and little agricultural use. Along the coast, from Cape May to Sandy Hook, are dunes and sandy beaches, offshore sand bars, and numerous islands.

The Piedmont, which lies northwest of the Coastal Plain, is the lowest and most northerly part of the Piedmont Plateau. Also called the Piedmont Lowland and the Triassic Lowland, the Piedmont is a low plains region marked by occasional outcrops of ancient basalt, called traprock. Some of the outcrops reach heights of more than 500 feet (150 m) above sea level. Among them are the Watchung Mountains, southwest of New-ark, and the clifflike Palisades, which overlook the Hudson River. The Piedmont is heavily urbanized and contains nearly all the largest cities of the state. Immediately to the east, beyond the Hudson River, is New York City.

The Highlands region lies northwest of the Piedmont. It consists of low, rounded mountain ridges and intervening valleys. Elevations of 1,100 to 1,400 feet (335 to 427 m) occur in the Allamuchy, Bearfort, Green Pond, Jenny Jump, Ramapo, and Schooleys mountains. Much of the regions was glaciated during the last Ice Age and is studded with clear, small lakes.

The Ridge and Valley region is in the extreme northwest. It consists of the Kittatinny Mountains and Kittatinny Valley— New Jersey's section of the Great Valley of the Appalachians, which extends from New York to Alabama. High Point, a 1,803-foot (550-m) peak in the Kittatinny Mountains, is the highest point in the state. Above Columbia, the Delaware River cuts through the Kittatinny Mountains in a deep notch called the Delaware Water Gap.

Two major rivers, the Delaware and the Hudson, border New Jersey. The Delaware, in the west, separates New Jersey from Delaware and Pennsylvania and, with its tributaries, drains roughly half of the state. The Hudson, in the northeast, forms part of the New York-New Jersey state line. Numerous short rivers flowing to the Atlantic drain the rest of the state. In the north are the Hackensack, Passaic, and Raritan rivers, which empty into arms of New York Bay. Farther south are the Toms, Mullica, Great Egg Harbor, and Maurice rivers.

Lake Hopatcong and Wanaque Reservoir, though relatively small, are the largest of the state's many inland waters, which total 319 square miles (826 km 2 ).

New Jersey has a continental climate that varies from north to south, with closeness to the ocean, and with increased elevation inland. Summers are warm to hot; winters are generally cold.

Average July temperatures range from about 70° to 77° F. (21° to 25° C.), the cooler parts of the state being in the mountains and, to a lesser extent, along the coast. Average January temperatures range from about 25° to 35° F. (-4° to 2° C.), the warmest area being the southern tip of the state. Extreme temperatures of more than 105° F. (41° C.) and less than -30° F. (-34° C.) have been recorded in the state. The length of the frost-free season ranges from about 130 days in some mountain locations to 230 days along the southern coast.

Precipitation is fairly well distributed throughout the year. The annual average varies from about 40 inches (1,020 mm) along the southeast coast to somewhat more than 50 inches (1,270 mm) in the north-central part of the state. Part of the precipitation occurs as snow. Only in the mountains does the annual snowfall reach 50 inches a year; the rest of the state gets considerably less.

Hurricanes and tornadoes occasionally strike the state.

More than a third of New Jersey is forest-covered, mostly with second-growth trees. In the northern and central parts of the state, forests are mainly mixed hardwoods, primarily oak, tulip, hickory, birch, gum, and maple. In the far north near the New York state line, there are stands of white pine, hemlock, and other evergreen trees as well as stands of mixed evergreens and hardwoods.

Forests in the southern part of the state are mostly pines, particularly pitch, short-leaf, and Virginia pines. One of the chief forested tracts is the Pine Barrens, north of the Mullica River.

A great variety of smaller plants grow throughout the state. Native hollies, blueberries, and cranberries are among the more distinctive plants.