guayule(redirected from guayules)
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guayule(wīyo͞o`lē, gwä–), multibranched flowering evergreen shrub, Parthenium argentatum, native to the deserts of the SW United States and N Mexico. Growing to 3 ft (1 m) in height, the guayule has leaves and outer stems that are covered with silvery hairs; its small yellow-white composite flowers are produced in clusters. Sometimes used as a landscape plant in dry areas, the shrub has been primarily of interest, since the early 1900s, as an alternative source of rubber, and was widely planted for that purpose in California and the Southwest during World War II. The rubber produced from the latex found in the bark of the stems is used in a number of products, including gloves for individuals allergic to latex from the Pará rubber treePará rubber tree
, large tree (Hevea brasiliensis) of the family Euphorbiaceae (spurge family), native to tropical South America and the source of the greatest amount and finest quality of natural rubber.
..... Click the link for more information. . Resin from the shrub is used as a wood preservative, and pulp from processing is used in particle board. The guayule is classified in the division MagnoliophytaMagnoliophyta
, 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).
..... Click the link for more information. , class Magnoliopsida, order Asterales, family Asteraceae.
(Parthenium argentatum), a rubber-bearing plant of the family Compositae. It grows in the deserts of the northern part of the Mexican plateau, as high as 2,000 m above sea level, and in Texas. It is an evergreen, heavily branched semishrub, reaching a height of 1 m, with a long branched tap root and numerous surface side roots. The leaves measure about 5-8 cm long, with pointed or lobed edges that may be notched or feathered, and contain 3-5 paired lobes. The long cauliform peduncles carry 7-30 small heads of flowers. The leaves, stems, and annual branches are covered with short, thick, silvery hairs. Rubber is found in the roots and the branches. Guayule also contains resin and ester oils.