PRICKLY encyclopedia topics

prickly heat (miliaria), inflammatory skin eruption due to obstruction of the sweat glands by keratin, the substance that forms the horny cells of the epidermis. It consists of blisterlike elevations with burning and itching, and is common in infants, obese persons, and those exposed to a hot, moist atmosphere for long periods of time. Relief may be obtained by applying soothing and drying lotions.

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prickly ash

prickly ash, name for two deciduous shrubs or small trees (Zanthoxylum americanum and Z. clava-herculis) of the family Rutaceae (rue family). They are native to E North America and have prickly twigs and foliage similar to that of the unrelated ash tree. A pungent aromatic principle in the bark has been used as a home remedy for various ailments including rheumatism and toothaches (hence the local name toothache tree). Z. clava-herculis, of more southerly distribution, is also known as Hercules'-club. Both Hercules'-club and prickly ash are names sometimes used for an unrelated plant of the family Araliaceae (ginseng family). Other Zanthoxylum species are the sources of Sichuan and Sansho peppercorns (Z. simulans and Z. piperitum, respectively) and of satinwood (Z. flavum). Prickly ash of the genus Zanthoxylum is classified in the division Magnoliophyta, class Magnoliopsida, order Sapindales, family Rutaceae. The family Araliaceae belongs to the order Apiales.

The Columbia Electronic Encyclopedia Copyright © 2004.
Licensed from Columbia University Press

pear, prickly

pear, prickly: see cactus.

The Columbia Electronic Encyclopedia Copyright © 2004.
Licensed from Columbia University Press

prickly pear

Engelmann prickly pear (Opuntia engelmannii)

Any of a group of flat-stemmed, spiny opuntia cacti (see cactus), native to the Western Hemisphere, or the edible fruit of certain species. Engelmann prickly pear (Opuntia engelmannii) and beaver tail cactus (O. basilaris) commonly occur in the southwestern U.S. The Indian fig (O. ficus-indica) is an important food in tropical and subtropical countries. Because their stems have a high water content, prickly pears can be used as forage crops and emergency stock feed during drought. Some species are cultivated as ornamentals and valued for their large flowers.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.