Geography of Illinois

Introduction to Geography of Illinois

Illinois, one of the Midwestern states of the United States. It is bounded by Wisconsin, Indiana, Kentucky, Missouri, and Iowa. Lake Michigan forms part of the eastern boundary. Illinois is the 25th largest state, with an area of 57,918 square miles (150,007 km2).

Physical Geography

Illinois is predominantly flat, lying within the Central Lowlands region of the United States. The surface slopes gradually downward from the northeast to the southwest and reaches its lowest point, 279 feet (85 m) above sea level, in the extreme southwest at the junction of the Mississippi and Ohio rivers. The state's average elevation is 600 feet (183 m) above sea level.

During the last Ice Age, glaciers covered the state as far south as Carbondale; only the extreme south and a small section of the northwest were free from glaciation. In most of the extreme south low, eroded plateaus extend into the state from Kentucky and Missouri. In the northwest section is the state's highest point, Charles Mound, reaching 1,235 feet (376 m). As the glaciers receded they left behind deep layers of debris.

Illinois is bordered by two of the nation's great rivers—the Mississippi and the Ohio. The Mississippi forms the state's western boundary. The rivers flowing southwesterly into it drain much of the state. The chief Mississippi tributary in Illinois is the Illinois River, flowing across the central part of the state. Tributaries of the Illinois include the Kankakee, Des Plaines, Fox, and Sangamon. Other rivers that join the Mississippi include the Rock, Kaskaskia, and Big Muddy. The Ohio River forms the Illinois-Kentucky border. Its main tributary in Illinois is the Wabash River, which forms part of the Illinois-Indiana border. Illinois rivers that flow into the Wabash include the Little Wabash and Embarras rivers.

Illinois has few large lakes. In northeastern Illinois are a number of small glacial lakes. Fox Lake, the largest, is part of the Chain O'Lakes, a group connected by the Fox River. Artificial lakes, formed by dams, are found in many parts of the state; among the large ones are Lake Shelbyville, Carlyle Lake, and Rend Lake. Many communities in northeastern Illinois get their water from Lake Michigan.

Illinois has a continental type of climate, with cold winters and hot summers. Because of the state's great length, temperature differences from north to south are often pronounced. Average January temperatures are 36° F. (2° C.) in Cairo in the extreme south, 20° F. (-7° C.) in Rockford in the north; average July temperatures are 81° F. (27° C.) in Cairo, 73° F. (23° C.) in Rockford. Illinois is subject to occasional severe storms, including tornadoes, violent thunderstorms, and blizzards.

Annual precipitation increases from an average 34 inches (860 mm) in the north to 43 inches (1,090 mm) in the south. Annual snowfall however, decreases north to south from an average of 30 inches (760 mm) to 10 inches (250 mm). Flooding often occurs in the early spring, especially when there are heavy rainfalls while snow and river ice are melting.

In the early 1800's, when rapid settlement began, tall prairie grasses covered most of northern and central Illinois. Forests covered the southern fourth of the state and extended as narrow strips along rivers far into the grasslands. By the early 20th century, most of the forests and all but tiny remnants of the grasslands had been turned into farmland.

Forests presently cover only about 10 per cent of the state. Virtually all the trees are second-growth hardwoods of commercial quality, mainly oaks. Most of the forests are privately owned and consist of scattered parcels on farms.

Economy

Illinois has long held a prominent position in the national economy, primarily as a producer of manufactured goods and farm products. A key factor in the state's economic success is its position as a chief junction of the national transportation network—particularly for air, highway, and railway routes. For several decades after World War II, manufacturing dominated the economy. Today, such activities as banking, insurance, publishing, and various services provide a growing share of the state's jobs. Adding a further measure of diversity is Chicago's place as a major center for wholesale trade and conventions and trade shows.

Illinois is one of the nation's leading manufacturing states by value of its products. Large-scale industrial development began in the last quarter of the 19th century with such activities as meat packing, flour milling, and the making of farm equipment. Chicago grew to be the center of manufacturing, but such cities as Peoria, Moline, Rockford, and East St. Louis also developed important industries. During World War II and in the following two decades heavy industry, especially the making of iron and steel, grew rapidly. By the late 1960's, however, the number of industrial workers had begun to decline. Illinois manufacturing industries were among the hardest hit by the nationwide recession of the late 1970's and early 1980's. Nevertheless, the state is still one of the nation's leading producers of such manufactured goods as machinery, particularly for farming and construction; computer and electronic equipment; metals and fabricated metal products; chemicals; and precision instruments. Food processing, one of the state's earliest industrial activities, is also of major importance.

Excellent soils, a long growing season, and adequate rainfall help make Illinois a national leader in farm output, by total value. Illinois farmland is among the most valuable in the United States. Farms occupy about 75 per cent of the state's land. Most farms are devoted to crops, with planted area accounting for much of all farmland. Soybeans and corn are the most important crops; nationally, Illinois usually ranks high in soybean and corn production. Also harvested in large amounts are hay, oats, and wheat. Central and southern Illinois are the main grain-growing regions, although grain is grown throughout the state. There are many truck farms and orchards, especially in the north. Hogs and cattle are the chief livestock raised. Poultry is also raised, mainly for eggs. The northern and western parts of the state are the principal dairying regions.

Fossil fuels make up more than 80 per cent of the value of mineral output. Illinois is one of the nation's largest producers of bituminous coal and has enormous reserves for future use. The mines, most of which are underground, are in the southern part of the state. Moderate amounts of petroleum are produced, mainly in the southeastern part of the state.

Other minerals produced in large amounts are industrial sand and gravel. Also important are stone, clays, and tripoli.

Illinois has a very well-developed transportation network. It has long been the leading railway center in the nation, with numerous major lines converging at Chicago. The state is served by a large number of Interstate highways and other high-speed limited-access routes. Chicago's O'Hare International Airport is among the busiest airports in the world.

The Illinois Waterway, a series of rivers and canals, is the transportation link between Lake Michigan and the Mississippi River. Illinois shipping is linked to Atlantic Ocean traffic by way of the Great Lakes and the St. Lawrence Seaway. The chief port facility in the state is Lake Calumet Harbor near Chicago.

The People

In 2000, the population density was 223.4 persons per square mile (86.3 per km2), slightly less than three times that of the United States as a whole. Almost half of the state's population lived in Cook County, in which Chicago is located.

Illinois's early settlers were largely English, Irish, Scottish, and German. The period of heavy immigration in the late 19th and early 20th centuries brought more Germans, Swedes, Italians, Poles, and Russians. The extreme south had a high percentage of blacks from the days of earliest settlement. Beginning in World War I the Chicago region received a steady influx of blacks from the southern states. In 2000 15.1 per cent of Illinois's population were black. People of Hispanic origin made up 12.3 per cent of the population.

Education

The state superintendent of education is responsible for the supervision of public schools in Illinois. The superintendent is selected by the state board of education, whose members are appointed by the governor. School attendance is compulsory from age 7 to age 16.

The first school in the state was a log mission school founded by Father Jacques Marquette at Starved Rock in 1675. The first college in Illinois was Illinois College, established at Jacksonville in 1830. Legislation providing for a free public school system was enacted in 1855. The nation's first coeducational high school was opened in Chicago in 1856. The nation's first public junior college was founded in 1901 in Joliet.

The largest institution of higher learning in the state is the University of Illinois, a land-grant school. It was incorporated as Illinois Industrial University in 1867 and received its present name in 1885. The Urbana-Champaign campus extends over more than 700 acres (280 hectares). The Chicago campus was opened in 1965 near downtown Chicago. Among the state's well-known privately supported schools are the University of Chicago, Northwestern University, and Illinois Institute of Technology, all in the Chicago area.

Government

Illinois is governed under its fourth constitution, adopted in 1970 and effective July 1, 1971. The governor heads the executive branch of government. Elected executive officials are the governor, lieutenant governor, secretary of state, comptroller, treasurer, and attorney general. All serve four-year terms.

The General Assembly (legislature) consists of a Senate of 59 members and a House of Representatives of 118 members. It con venes in January of each year. State senators serve terms of either two or four years and representatives serve terms of two years.

The Supreme Court has seven justices elected for 10-year terms. Other courts include an appellate court, whose judges are elected for 10 years, and circuit courts, whose judges are elected for 6 years.

Illinois has 102 counties. The state is represented in Congress by 2 senators and 19 representatives.