orange, name for a tree of the family Rutaceae (rue, or orange, family), native to China and Indochina, and for its fruit, the most important fresh fruit of international commerce. Its physical characteristics (especially the rich citric acid and vitamin content of the fruit) and history of cultivation are similar to those of the other types of citrus fruits, all of which are species of Citrus.

Among the commercially important species of oranges are the sweet, or common, orange (C. sinensis), which furnishes most of the varieties for commercial growing, including the Baiá, or Washington, navel (a winter orange), and the Valencia (a summer orange); the sour, or Seville, orange (C. aurantium), which is grown in the United States chiefly as understock on which to bud sweet orange varieties, although in Europe its fruit is much used in marmalade; the mandarin (C. reticulata or nobilis), or the "kid glove," or loose-rind, group of oranges, which includes the Satsuma varieties, known for their hardiness, tangerines, and clementines. Oranges hybridize freely. The Temple orange is a cross between a mandarin and a sweet orange; the citrange a cross between the inedible trifoliate orange (C. trifoliata) and a sweet orange; and the tangelo is produced by crossing a tangerine and a grapefruit.

Columbus brought the orange to the West Indies, and it is known that orange trees were well established in Florida before 1565 and were growing in California by 1800. The orange now grows in the warm parts of all continents. Flowers and fruits in all stages of development are on the tree throughout the year, although a large portion of the fruits ripen at one time. The orange is attacked by many insects and fungus diseases and is quite sensitive to frost. If the fruits are picked when still "green" (though fully mature), they must undergo a bleaching or degreening process to bring out the orange or yellow color in their rinds. Some oranges are artificially colored and waxed before marketing.

Most oranges, like other citrus fruits, are consumed fresh or made into juice. The fruit and rind are also much used in marmalade, preserves, flavoring, and confections. Some varieties yield essential oils used in perfume. The flower is a favorite for bridal decoration and is the state flower of Florida. The yellow wood, which is hard and close-grained, is manufactured into small articles.

Orange is classified in the division Magnoliophyta, class Magnoliopsida, order Sapindales, family Rutaceae.

mock orange: see saxifrage.

William of Orange: see William the Silent; William II, prince of Orange; William III, king of England.

West Orange, town (1990 pop. 39,103), Essex co., NE N.J., a residential suburb of Newark; set off from Orange 1862, inc. 1900. "Glenmont," Thomas Edison's home in Llewellyn Park, and his laboratory (now a museum) are included in the Edison National Historic Site (see National Parks and Monuments, table).

South Orange, village (1990 pop. 16,390), Essex co., NE N.J., inc. 1869. Mostly residential, it has some small industries. Seton Hall Univ. is in South Orange.

Osage orange: see mulberry.

Orange River, chief river of S Africa, c.1,300 mi (2,090 km) long, rising in the Maluti Mts., N Lesotho. It flows SW through Lesotho, then meanders northwest and west through central South Africa, forming the SW boundary of Free State and part of the South Africa-Namibia line before entering the Atlantic Ocean at Oranjemund. The Vaal River is its chief tributary. The lower Orange River flows through the southern part of the Kalahari and Namib deserts; in very dry years it does not reach the sea. At the mouth of the river are rich alluvial diamond beds. Shoals, falls (Aughrabies Falls is 400 ft/122 m high), irregular flow, and a sandbar at its mouth limit navigation, but the river is used extensively for irrigation. The South African Orange River Project, which includes the Gariep and Vanderkloof dams, provides water for irrigation, hydroelectric power generation, and municipal water supplies. Tunnels divert water to the Great Fish and Sundays rivers.

Orange Free State, former province, South Africa: see Free State.

Orange, town (1990 pop. 28,136), Vaucluse dept., SE France. An agricultural market center, the town also produces refined sugar, pâtés, preserves, wool, and shoes. Tourism is also important. Orange was an earldom probably founded by Charlemagne. It became the capital of a principality (12th cent.) and was passed from family to family and eventually (1554), through inheritance, to William the Silent, of the house of Nassau. Among William's descendants were William III of England and the ruling family of the Netherlands. Orange was conquered (1672) by Louis XIV and confirmed in French possession by the Treaty of Ryswick (1697) and the Peace of Utrecht (1713), although the title remained with the Dutch princes of Orange. The town has important Roman ruins, notably a triumphal arch (1st cent. A.D.) and an amphitheater (c.A.D. 120) which is still in use.

Orange. 1 City (1990 pop. 110,658), Orange co., S Calif.; inc. 1888. Citrus fruits and nuts are packed, processed, and shipped; rubber and plastic products, electronic components, aircraft parts, and industrial furnaces are manufactured. The city grew rapidly in the late 20th cent. Founded as Richland, the city was renamed in 1875. Chapman Univ. is there.

2 Town (1990 pop. 12,830), New Haven co., SW Conn., a residential suburb of New Haven, on the Housatonic; settled 1720, set off from Milford 1822, inc. 1921. It is a major retail center; manufactures include metal products, furniture, electronic and transportation equipment, and foods. The town's first house (1720) still stands.

3 City (1990 pop. 29,925), Essex co., NE N.J.; settled c.1675, set off from Newark 1806, inc. as a city 1872. Orange and the surrounding municipalities of East Orange, West Orange, South Orange, and Maplewood are known as "The Oranges," a single suburb of Newark and New York City. Although chiefly residential, Orange has some manufacturing.

4 City (1990 pop. 19,381), seat of Orange co., SE Tex., a deepwater port on the Sabine River at its junction with the Intracoastal Waterway; settled c.1800, inc. 1858. It is a port of entry, with shipyards, oil and gas wells, and major petrochemical plants. Steel, rubber and paper products, and plastics are manufactured. Cattle, hogs, honey, and wine are also produced. The U.S. navy has a mothballed fleet there.

Judd, Orange, 1822-92, American agricultural editor and publisher, b. near Niagara Falls, N.Y., grad. Wesleyan Univ., 1847. At Wesleyan he built (1871) the Orange Judd Hall of Natural Science and secured through his gifts the establishment of the first agricultural experiment station in the country. He became in 1853 joint editor and owner of the American Agriculturist, which he made into one of the leading farm papers of the country.

East Orange, city (1990 pop. 73,552), Essex co., NE N.J.; settled 1678, separated from Orange and inc. 1863. A residential city adjacent to Newark, it also has various manufactures. Upsala College, here since 1893, closed in 1995.

Agent Orange, herbicide used by U.S. forces during the Vietnam War to expose enemy guerrilla forces in forested areas. Agent Orange contains varying amounts of dioxin. Exposure to the defoliant has been linked with chemical acne, non-Hodgkin's lymphoma, Hodgkin's disease, and soft-tissue sarcoma. Many soldiers were exposed to Agent Orange in the Vietnam War. Afflicted veterans brought a class-action suit against manufacturers of Agent Orange, which was settled out of court by the establishment of a fund to compensate them and their families for any disabilities. That settlement, however, covered only those who became ill by 1994 and, as a result of a 2003 Supreme Court decision, veterans who became ill after 1994 can sue the herbicide's manufacturers. The herbicide has also been blamed for a significantly higher than normal rate of birth defects in areas of Vietnam that were sprayed; tests have shown persistent high levels of dioxin in the local environment and in people living there.

North American plant (Asclepias tuberosa) of the milkweed family, a stout, rough-haired perennial with long horizontal roots. The leafy, erect, somewhat branching stem is about 1–3 ft (0.3–0.9 m) tall. In midsummer it bears numerous clusters of bright orange flowers. Unlike most milkweeds, it has a scanty milky juice. It is native to dry fields and is often planted in wild gardens or grown as a border plant.

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Any of several species of small trees or shrubs in the genus Citrus of the rue (or citrus) family and their fruits. Grown in tropical and subtropical regions, the nearly round fruits have leathery, oily rinds and edible, juicy inner flesh rich in vitamin C. Key commercial species include the China (sweet, or common) orange; the mandarin orange (including tangerines); and seedless navel oranges. The tree has broad, glossy, medium-size evergreen leaves, leafstalks with narrow wings, and very fragrant flowers. It bears fruit abundantly for 50–80 years. Oranges do not improve in quality off the tree, so they are picked when fully ripe. A sizeable portion of the U.S. crop is processed for frozen concentrated juice. By-products include essential oils, pectin, candied peel, orange marmalade, and stock feed.

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Dutch Willem Alexander Paul Frederik Lodewijk

(born Feb. 19, 1817, Brussels, Belg.—died Nov. 23, 1890, Apeldoorn, Neth.) King of The Netherlands and grand duke of Luxembourg (1849–90). Son of William II, he succeeded to the throne on his father's death in 1849. Opposed to the liberal constitution of 1848, he adopted an anti-Catholic posture and from 1862 to 1868 was able to rule through the cabinet. He tried to sell his sovereignty over Luxembourg to France (1867) but yielded to Prussia's demand that the area be independent. Following this crisis, his influence over parliament declined. On his death, he was succeeded by his daughter, Wilhelmina.

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German Friedrich Wilhelm

(born Aug. 3, 1770, Potsdam, Prussia—died June 7, 1840, Berlin) King of Prussia (1797–1840). The son of Frederick William II, he pursued a policy of neutrality in the early years of the Napoleonic Wars, which accelerated the decline of Prussia's prestige. Prussia joined the third coalition against France in 1806 and suffered crushing defeat at the Battles of Jena and Auerstedt. Defeat convinced the king of the need to make decisive changes. He allowed Prussian statesmen such as Karl August, prince von Hardenberg, and Karl, imperial baron vom Stein, to make domestic reforms, though the state remained absolutist. The Congress of Vienna confirmed Prussia's acquisition of Westphalia and much of Saxony, but the last 25 years of the king's reign brought a downward trend in Prussia's fortunes.

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River, southern Africa. It rises in the Lesotho Highlands as the Sinqu River and flows west as the Orange across South Africa. It passes the southern edge of the Kalahari Desert and winds through the Namib Desert before draining into the Atlantic Ocean in South Africa. It forms the border between South Africa and Namibia. It is about 1,300 mi (2,100 km) long. There are some irrigated sections along the river and many dams but no large towns.

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Former province, central South Africa. Before the arrival of the Europeans, the area was the home of Bantu-speaking peoples. Afrikaners came in large part during the Great Trek of the 1830s. Britain administered the territory from 1848 to 1854; then the independent Orange Free State was established. British rule was reimposed following the South African War in 1902, though self-government was later restored. In 1910 it became the Orange Free State province of the Union of South Africa (from 1961 the Republic of South Africa). After the South African elections of 1994, it became the province of Free State. Blacks make up about 80percnt of the population; most of the whites speak Afrikaans. The province's capital is Bloemfontein.

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Mixture of herbicides. It contains approximately equal amounts of esters of 2,4-D (2,4-dichlorophenoxyacetic acid) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) and trace amounts of dioxin. About 13 million gallons were sprayed by U.S. military forces onto Vietnam's forests and crops during the Vietnam War, with the dual purpose of destroying cover for enemy movements and destroying food sources. Exposure to Agent Orange has been blamed for an abnormally high incidence of miscarriages, skin diseases, cancers, birth defects, and malformations among Vietnamese and of cancers and other disorders in U.S., Australian, and New Zealand servicemen and their families.

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