Palm : common name for members of the Palmae, a large family of chiefly tropical trees, shrubs, and vines. Most species are treelike, characterized by a crown of compound leaves, called fronds, terminating a tall, woody, unbranched stem. The fruits, covered with a tough fleshy, fibrous, or leathery outer layer, usually contain a large amount of endosperm in the seed (stored food). Although the palms are of limited use in the United States and other temperate areas, their economic importance in the tropical regions can exceed that of the grasses. Members of the family often furnish food, shelter, clothing, and other necessities of life for entire populations; an ancient Hindu song about the Palmyra palm ( Borassus flabelliformis ) of India enumerates 801 uses for the plant. Among the most important palms providing food and other products are the coconut , date , and sago . Palm sugar (jaggery) is obtained from the sap of several palms, e.g., species of Phoenix, Cocos, Arenga (in India), and Raphia (in Africa). Palm toddy, or wine, is made especially in Africa and Southeast Asia. The fruit of the betel palm provides the world's most-used masticatory. Carnauba wax is obtained from a Brazilian species. Among the important palm fibers are raffia and rattan . Daemonorops draco yields dragon's blood , a resin. Another palm-fruit product, tagua , is used as a substitute for ivory. Species native to the United States include the tall royal palm of Florida and Cuba (usually Roystonea regia in Florida) and the California fan palm ( Washingtonia filifera ) of the Southwest and Mexico, much planted as an avenue ornamental. The palmetto palm is the characteristic underbrush plant of the SE United States. Cabbage palm is a name applied to several species whose young heads of tender leaves are cooked as vegetables; these include the coconut palm, a royal palm ( R. oleracea ), and the cabbage palmetto ( Sabal palmetto ). The largest known plant seed, enclosed in a fruit weighing up to 40 lb (18 kg), is borne by Lodoicea maldivica, a palm of the Seychelles, variously called the Seychelles nut palm, the coco-de-mer, or the double coconut. The talipot palm, Corypha umbraculifera, has leaf blades that may be up to 16 ft (4.9 m) across and the largest compound inflorescence, or flowerhead, in the plant kingdom. Palm oil is the fat pressed from the fibrous flesh of the fruit of many palms, principally the coconut palm, the African oil palm ( Elaeis guineensis ), the peach palm ( Bactris gasipaes ), the babassu palm ( Orbignya species, especially O. phalerata ), and other South American species. Commercial palm oils are used for soaps and candles, lubricants, margarine, fuel, feed (chiefly the caked residue remaining after the oil has been expressed), and many other purposes. In the tropics much of the palm oil produced (often by crude extraction methods) is consumed locally. The total output of palm oil equals that of all other nondrying oils combined. The palm family is classified in the division Magnoliophyta , class Liliopsida, order Arecales.
Cycads are a group of palm-like plants. The cycads are a subset of the gymnosperms , the seed-bearing, non-flowering plants. The cycads were very common in the Mesozoic era especially during the Jurassic period . In fact, the Jurassic period is known as the Age of Cycads. Today cycads are only found in the tropical or subtropical areas of the world. There are three main families of Cycads today: Cycadaceae, Stangeriaceae, and Zamiaceae. The best known cycad is the sago palm which is often kept as a houseplant. The sago palm is not related to the true palms.
Cycad : any plant of the order Cycadales, tropical and subtropical palmlike evergreens. The cycads, ginkgoes , and conifers comprise the three major orders of gymnosperms, or cone-bearing plants (see cone and plant ). The cycads first appeared in the Permian period. They are the most primitive of the living seed-bearing plants and in many ways resemble the ferns . Some have tuberous underground stems, with the crown of leathery, glossy, fernlike leaves springing from ground level; others have a columnar stem, usually 6 to 10 ft (1.8-3.1 m) high (though the corcho of Cuba reaches 30 ft/9.1 m), and are often mistaken for palms. There are 11 genera composed of less than 150 species, some found in very restricted areas. Many cycads (e.g., the fern palm of the Old World tropics and the nut palm of Australia) bear poisonous nutlike seeds. The pith of the coontie ( Zamia floridana ) yields a starch called Florida arrowroot or sago ; the coontie is often called sago palm. Cycads are grown as ornamentals in warm regions and in greenhouses. The cycads are classified in the division Pinophyta , class Cycadopsida.
From : http://encyclopedia.thefreedictionary.com
2004-07-29 00:05:12
