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spurge (spûrj), common name for members of the Euphorbiaceae, a family of herbs, shrubs, and trees of greatly varied structure and almost cosmopolitan distribution, although most species are tropical. In the United States the family is most common in the Southeast.
Many plants of the spurge family have reduced fleshy leaves, in particular the vast Euphorbia genus of approximately 1,600 subtropical and warm-temperate species. These cactuslike plants, comprising most of the species commonly called spurge, have spiny, jointed stems and are among the most common Old World desert succulents. The euphorbias and the cacti illustrate the biological phenomenon of convergent evolution, in which unrelated groups of organisms, subject to the same environmental pressures, gradually develop similar structures. The euphorbias exhibit another family trait: "naked flowers" (i.e., flowers lacking petals and sometimes sepals) that are enclosed in a bract envelope, from which they emerge during the flowering period to permit pollination.
Many species are cultivated for their brilliant, showy bracts as well as for their frequently colorful foliage. These include snow-on-the-mountain (E. marginata), native to the United States; the cypress spurge (E. cyparissias), a favored cemetery plant that was introduced from Europe and naturalized; the scarlet-bracted greenhouse plant crown-of-thorns (E. splendens), native to Madagascar; and the poinsettia (for J. R. Poinsett Poinsett, Joel Roberts , 1779–1851, American diplomat and politician, b. Charleston, S.C. In 1810 he was sent as a special commissioner to South America to investigate political conditions of the countries struggling for independence.
Other Spurges and Their Uses
Many spurges are of great economic importance as a source of food, drugs, rubber, and other products. The sap of most species is a milky latex, and the source of a very large part of the world's natural rubber rubber, any solid substance that upon vulcanization becomes elastic; the term includes natural rubber (caoutchouc) and synthetic rubber. The term elastomer
Other valuable commercial products of this family are castor oil castor oil, yellowish oil obtained from the seed of the castor bean. The oil content of the seeds varies from about 20% to 50%. After the hulls are removed the seeds are cold-pressed.
Various spurges provide medicines, dyes, oils, and other products; primitive peoples utilized the poisonous saps of other spurges on arrow tips and to poison fish. The presence of poisonous substances in many euphorbias and in a number of other spurges has led these to be classed as noxious pests, especially when they grow as weeds on livestock ranges.
Spurge is classified in the division Magnoliophyta Magnoliophyta , division of the plant kingdom consisting of those organisms commonly called the flowering plants, or angiosperms. The angiosperms have leaves, stems, and roots, and vascular, or conducting, tissue (xylem and phloem).
spurgeOne of the largest flowering-plant genera (Euphorbia), with more than 1,600 species. It takes its common name from a group of annual herbs used as purgatives, or spurges. Many spurges are important as ornamentals or as sources of drugs; many others are weeds. One of the best-known is the poinsettia. Euphorbia is part of the family Euphorbiaceae, which contains about 7,500 species of flowering annual and perennial herbs and woody shrubs or trees in 275 genera; most are found in temperate and tropical regions. Flowers usually lack petals; those of Euphorbia are borne in cup-shaped clusters. The fruit is a capsule. Leaves are usually simple. The stems of many species contain a milky latex. In addition to Euphorbia, economically important family members include the castor-oil plant, croton, cassava, and rubber tree.
any of various euphorbiaceous plants of the genus Euphorbia that have milky sap and small flowers typically surrounded by conspicuous bracts. Some species have purgative properties
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