squirrel corn: see fumitory.

corn laws, regulations restricting the export and import of grain, particularly in England. As early as 1361 export was forbidden in order to keep English grain cheap. Subsequent laws, numerous and complex, forbade export unless the domestic price was low and forbade import unless it was high. The purpose of the laws was to assure a stable and sufficient supply of grain from domestic sources, eliminating undue dependence on foreign supplies, yet allowing for imports in time of scarcity. The corn law of 1815 was designed to maintain high prices and prevent an agricultural depression after the Napoleonic Wars. Consumers and laborers objected, but it was the criticism of manufacturers that the laws hampered industrialization by subsidizing agriculture that proved most effective. Following a campaign by the Anti-Corn-Law League, the corn laws were repealed by the Conservative government of Sir Robert Peel in 1846, despite the opposition of many of his own party, led by Lord George Bentinck and Benjamin Disraeli. With the revival of protectionism in the 20th cent., new grain restriction laws have been passed, but they have not been as extensive as those of earlier times.

corn earworm or cotton bollworm, destructive larva of a moth, Heliothis zea. Also known as tomato fruitworm, the larva attacks a variety of crops, boring into and feeding on the developing fruits—tomatoes, corn kernels, or cotton bolls. The adult moth is pale yellow. It is classified in the phylum Arthropoda, class Insecta, order Lepidoptera, family Noctuidae.

corn borer or European corn borer, common name for the larva of a moth of the family Pyralidae, introduced from S Europe into the Boston area in 1917. The corn borer, Ostrinia nubilalis, has steadily spread southward into the Gulf States and northward and westward across the continent to the Rocky Mts. It also still occurs in most of Europe and parts of Asia. The full-grown larva is about 1 in. (2.5 cm) long, with a dark brown head and pinkish body. It is a major pest of all types of corn, its host preference, but also attacks many other cultivated crops (e.g., sorghum, soybeans, and potatoes) and flower plants (e.g., dahlias, asters, and gladioli). The newly hatched yellowish larvae cause damage by feeding on the leaves of the host plant; older larvae bore into the stalk thereby severely weakening the plant and causing ear damage, which results in a loss in yield and reduction of quality. The full-grown larvae overwinter in cornstalks, corncobs, and debris on the ground. Adults emerge in the spring and are brownish with zigzag streaks across the tips of the forewings. There are sometimes more than one generation per year depending on an increased length of the host's growing season. Control of these pests is complicated by the fact that the larvae also infest common weeds and wild grasses growing near the cornfields. For insecticidal control, see bulletins of the U.S. Dept. of Agriculture. Corn borers are classified in the phylum Arthropoda, class Insecta, order Lepidoptera, family Pyralidae.

corn, in botany. The name corn is given to the leading cereal crop of any major region. In England corn means wheat; in Scotland and Ireland, oats. The grain called corn in the United States is Indian corn or maize (Zea mays). The part of the United States where most of the corn is grown, including Ohio, Illinois, Indiana, Missouri, Kansas, Iowa, and Nebraska, is known as the Corn Belt.

The Corn Plant

The corn plant has a pithy noded stalk supported by prop roots. The staminate (male) flowers form the tassel at the top of the plant. The pistillate (female) flowers are the kernels on the cob, which is enclosed by a leafy husk beyond which extend threadlike styles and stigmas (the silk), which catch the pollen. The corn plant with its ornamental tassel and ears has been a motif of American art since prehistoric times.

The plant is a grass that was domesticated and cultivated in the Americas long before Europeans reached the New World. It is so changed from the ancestral wild grass that its original form has not been identified with certainty, and it has been so adapted to cultivation that it cannot sustain itself without human cultivation. It is probably a complex hybrid of several related New World grasses, e.g., teosinte (Euchlaena mexicana), a tropical American fodder plant in which the seeds are not united in a cob. The Native Americans had many varieties of corn, e.g., sweet corn, popcorn, and corn for corn meal. White, yellow, red, and blue corn were grown as distinct strains.

Development of Hybrids

The easily produced and readily identifiable strains of corn made it a favorite subject for experimental genetics. The development of hybrid corn seed was an early (beginning of the 20th cent.) and revolutionary introduction of the principles of theoretical science into practical agriculture. At first ridiculed, the scientifically developed hybrids came to represent most commercially grown corn types. They resulted in higher yields, increased sugar and lowered starch content, and uniform plants bred to specification for mechanical harvesting. Most recently, genetic engineering has produced corn with added sweetness, disease resistance, and other desired traits.

Uses

As human food, corn is eaten fresh or ground for meal. It is the basic starch plant of Central and Andean South America, where it is still hand ground on metates to be made into tamales, tortillas, and other staple dishes. In the S United States it is familiar as hominy, mush, and grits. Starch, sugar, and oil are also extracted for many products, but the chief use of corn is as animal fodder. It is the primary feed grain of the United States, and in Europe this is almost the only use of corn. Corn is also as a raw material in the manufacture of ethanol for fuel.

European corn borer: see corn borer.

Corn Belt, major agricultural region of the U.S. Midwest where corn acreage once exceeded that of any other crop. It is now commonly called the Feed Grains and Livestock Belt. Located in the north central plains, it is centered in Iowa and Illinois and extends into S Minnesota, SE South Dakota, E Nebraska, NE Kansas, N Missouri, Indiana, and W Ohio. Large-scale commercial and mechanized farming prevails in this region of deep, fertile, well-drained soils and long, hot, humid summers. The belt produces much of the U.S. corn crop, but agriculture has diversified; soybeans are an important yield. Winter wheat and alfalfa are also significant crops in the area.

Anti-Corn-Law League, organization formed in 1839 to work for the repeal of the English corn laws. It was an affiliation of groups in various cities and districts with headquarters at Manchester and was an outgrowth of the smaller Manchester Anti-Corn-Law Association. Richard Cobden and John Bright were its leading figures. The league won over Sir Robert Peel to its views, and the corn laws were repealed in 1846.

Cereal grain plant of the family Poaceae (or Gramineae), probably native to Africa, and its edible starchy seeds. All types raised chiefly for grain belong to the species Sorghum vulgare, which includes varieties of grain sorghums and grass sorghums (grown for hay and fodder), and broomcorn (used in making brooms and brushes). The strong grass usually grows 2–8 ft (0.5–2.5 m) or higher. The seeds are smaller than those of wheat. Though high in carbohydrates, sorghum is of lower feed quality than corn. Resistant to drought and heat, sorghum is one of Africa's major cereal grains. It is also grown in the U.S., India, Pakistan, and northern and northeastern China. Substantial quantities are also grown in Iran, the Arabian Peninsula, Argentina, Australia, and southern Europe. The grain is usually ground into meal for porridge, flatbreads, and cakes.

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Sweet syrup produced by breaking down (hydrolyzing) cornstarch (a product of corn). Corn syrup contains dextrins, maltose, and dextrose and is used in baked goods, jelly and jam, and candy. High-fructose corn syrup is widely used in the manufacture of soft drinks and other foods because it is considerably cheaper than sucrose.

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or cotton bollworm or tomato fruitworm

Moth larva (Heliothis zea, family Noctuidae) that damages corn, tomato, cotton, and other seasonal crops. The smooth, fleshy, green or brown caterpillars feed on corn kernels near the tip of the ear and burrow into tomatoes and cotton bolls. Four or five generations of the pale brown adult moths, with wingspans of 1.3 in. (3.5 cm), are produced annually.

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or maize

Cereal plant (Zea mays) of the family Poaceae (or Gramineae). It originated in the New World and has been introduced globally. American Indians taught colonists to grow corn, including some varieties of yellow corn that are still popular as food, as well as varieties with red, blue, pink, and black kernels, often banded, spotted, or striped, that today are regarded as ornamental and in the U.S. are called Indian corn. The tall, annual grass has a stout, erect, solid stem and large narrow leaves with wavy margins. Corn is used as livestock feed, as human food, and as raw material in industry. Though it is a major food in many parts of the world, it is inferior to other cereals in nutritional value. Inedible parts of the plant are used in industry—stalks for paper and wallboard; husks for filling material; cobs for fuel, to make charcoal, and in the preparation of industrial solvents. Corn husks also have a long history of use in the folk arts for objects such as woven amulets and corn-husk dolls. Corn is one of the most widely distributed of the world's food plants. In the U.S. corn is the most important crop, but slightly more acres of soybeans are planted.

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Traditional area, midwestern U.S. Roughly covering western Ohio, Indiana, Illinois, Iowa, southern Minnesota, eastern South Dakota, Missouri, eastern Nebraska, and eastern Kansas, it is a region in which corn and soybeans are the dominant crops. Many farms are family-operated and average more than 300 acres (120 hectares). Despite the name, the region is agriculturally diverse, raising various feed-grains and livestock.

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