Difference between revisions of "Cactus"

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__NOTOC__{{Plantbox
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| name = ''Cactaceae''
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| common_names = Cactus
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| growth_habit = various, succulent
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| high = 1cm to 19m
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| wide =    <!--- 65cm (25 inches) -->
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| origin =    <!--- Mexico, S America, S Europe, garden, etc -->
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| poisonous =    <!--- indicate parts of plants which are known/thought to be poisonous -->
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| lifespan =    <!--- perennial, annual, etc -->
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| exposure =    <!--- full sun, part-sun, semi-shade, shade, indoors, bright filtered (you may list more than 1) -->
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| water =    <!--- frequent, regular, moderate, drought tolerant, let dry then soak -->
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| features =    <!--- flowers, fragrance, fruit, naturalizes, invasive -->
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| hardiness =    <!--- frost sensitive, hardy, 5°C (40°F), etc -->
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| bloom =    <!--- seasons which the plant blooms, if it is grown for its flowers -->
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| usda_zones =    <!--- eg. 8-11 -->
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| sunset_zones = see genus/species
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| color = IndianRed
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| image = Echinocactus grusonii kew.jpg
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| image_width = 240px    <!--- leave as 240px if horizontal orientation photo, or change to 180px if vertical -->
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| image_caption = Echinocactus grusonii is a popular species in cultivation
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| regnum = Plantae
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| divisio = Magnoliophyta
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| classis = Magnoliopsida
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| ordo = Caryophyllales
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| familia = Cactaceae
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| genus =
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| species =
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| subspecies =
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| cultivar =
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}}
 
{{Inc|
 
{{Inc|
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Cactaceae (from the old Linnaean genus Cactus, a name used by the ancients to denote any spiny plant). Cactus Family. Fig. 41. Fleshy plants with watery or milky juice, a great reduction or complete absence of foliage, and very thick, rather sparingly branched, rarely unbranched stems, which are cylindrical, globular, flattened, or fluted, and often constricted or jointed: leaves alternate, flat and leaf-like in Pereskia, scale-like or absent in other genera, usually bearing bundles of spines in the axils, which are trichomes, and which are of two kinds, long and stout, or minute and needle-like: flowers bisexual, mostly regular, perigynous or epigynous; sepals and petals rarely 8-10, usually very many, similar; stamens many, inserted spirally or in groups on inside of the receptacle; ovary inferior, 1-celled, with 3 to many parietal placentae; ovules numerous; style 1; stigmas as many as the placenta: fruit a berry; embryo straight or curved.
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Cactus or cacti. The plants correctly designated by this name constitute the family Cactaceae. Scarcely any group in the whole plant kingdom is more remarkable for its strange and varied forms, the beauty of its [[flower]]s, and wonderful adaptation to desert life. It is not, however, confined to desert regions; for in the moist forests of the tropics of the New World it is represented by a number of interesting forms often epiphytal or scrambling in their [[habit]] of growth, with beautiful flowers and sometimes with delicious [[edible]] [[fruit]].{{SCH}}
  
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The Cacti are almost entirely confined to the dry regions of tropical and subtropical America. Mexico is the center of this distribution, but the Cactaceae extend from New York to Patagonia. A species of Rhipsalis has lately been found indigenous in West Africa. The family is related to the Begoniaceae, Loasaceae, and Passifloraceae. The peculiar habit, perianth of many similar parts, many stamens, and inferior 1-celled ovary are distinctive. The Cactaceae is divided into three groups: (1) Cereus group, with receptacle extended in a tube beyond the ovary (perigynous), and no hooked spines; (2) Opuntia group, tube of the receptacle wanting, hooked spines usually present; (3) Pereskia group, with foliaceous leaves, panicled flowers, and no hooked spines.
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===Range===
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The Cactaceae are confined to America, the only apparent exception being the genus [[Rhipsalis]], composed of plants with the habits of the mistletoe, growing on the trunks and branches of trees, and bearing small pellucid glutinous berries. This genus, endemic in tropical America, has found its way to Africa, the island of Mauritius and even to Ceylon; and several opuntias, or [[prickly pear]]s, occur on the shores of the Mediterranean, in South Africa, and Australia, where they have made themselves so thoroughly at home as to be regarded by many writers as indigenous. The Cactaceae are not confined to [[tropical]] or even semi-tropical regions. At least two species of [[Opuntia]] extend northward into British Columbia, and species of [[Echinocereus]], [[Echinocactus]], and [[Mamillaria]] are found in the state of Colorado. The xerophytic forms flourish especially in the southwestern United States, the Mexican plateau, the peninsula of Lower California, where there are great cactus forests, and the vicinity of Tehuacan, in the southern part of the Mexican state of Puebla, a region celebrated for its remarkable and gigantic tree-like forms related to the genus [[Cereus]].{{SCH}}
  
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The seeds of Rhipsalis, an epiphytic genus, are often viscid so as to adhere to tree trunks and the like. The ovaries of some Cactaceae are imbedded in the tissue of the stem. In this family, the thick stem is a water-storing organ. The flattened or fluted condition of the stem of most species is probably an adaptation which allows these stems to swell when water is abundant and contract when it is scarce without danger of rupturing the cuticle. The variation in size and form among cacti is very great. The largest species is Carnegiea giganteus of Mexico, candelabra-like, 60 feet high.
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To the southward, the family extends to Chile and Argentina. Giant torch thistles and echinocacti are scattered over the pampas of Uruguay, and melon-shaped echinopses amid the snows of the lofty plateau of Bolivia.{{SCH}}
  
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The fruit of Opuntia Ficus-indica, now naturalized in the Mediterranean region, is there eaten under the name of Indian fig. Opuntia Tuna of tropical America is the prickly pear, an edible fruit. Opuntia vulgaris of the eastern United States is also eaten under the name of prickly pear or Indian fig. Fruits of Cereus triangularis, C. gigantcus, and C. Thurberi are much prized. The stem and flowers of C. grandiflorus are used in medicine, producing an action on the heart. Vermifugal properties are found in many Cactaceae. An alcoholic drink is made by the Mexicans from the sap of species of Cereus. The cochineal insect, a scale insect yielding the well-known dye, cochineal, lives upon species of Opuntia, Pereskia, and Nopalea, in tropical America.
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The genus [[Mamillaria]], so well represented in the southwestern United States and Mexico, is almost absent from Central America, the representative genera of that region as well as of the warm Huasteca region of eastern Mexico being [[Cereus]], [[Pereskia]], [[Pereskiopsis]], [[Nopalea]], and Opuntia; while the "turk's-head” or "melon cacti" are chiefly West Indian.{{SCH}}
  
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The total number of genera of Cactaceae which have been described up to the present time is about 70, although Dr. Karl Schumann, who monographed the family in 1899, recognized but 21. Of the many genera described, most are good and will probably stand. A rational and uniform treatment of the family will doubtless show that there are no less than 75 tenable genera. The total number of names published is something over 3,800. This includes many species that have been transferred from one genus to another. The number of species recognized by Schumann is something less than 700. Many of these species of Schumann, however, are known to be aggregates, and it is not unlikely that there are about 1,200 species in the family.
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===Structure===
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[[Image:Cactus_arizona.jpg|thumb|[[Saguaro]] cactus in [[Arizona]], USA. This species is well known from [[Western (genre)|Western films]].]]
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[[Image:Pereskia grandifolia3.jpg|thumb|left|''Pereskia grandifolia'': ''[[Pereskia]]'' is a weakly succulent genus, which also possesses leaves, and is believed to be very similar to the ancestor of all cacti.]]
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The peculiar structure of columnar, opuntioid, and melon-shaped cacti is undoubtedly the result of excessive dryness of the climates in which they occur, to protect themselves from which they have been obliged to store up water and to reduce their transpiration as low as possible. They have a more or less pronounced woody axis surrounded by pulpy cellular tissue (parenchyma) in which the water-supply is stored. The stomata are usually situated in depressions or grooves in the leathery cuticle; and as an additional means for checking transpiration, the cell-sap is nearly always mucilaginous, while in some forms latex cells are present, filled with milky or gummy fluid which hardens on exposure to the air and effectively heals wounds in the soft fleshy plant. Certain species of Echinocactus (viznagas) are like great barrels studded with spines and filled with pulp of the consistency of watermelon rind, which is sometimes made into conserves like citron (dulces de viznaga). Other forms, like species of Pereskia, Pereskiopsis, and arboreous opuntias have hard, woody stems and branches. The reticulated skeletons of certain species of opuntia are manufactured into walking-sticks, legs of furniture, napkin rings, and even into veneering for woodwork. In Lower California and some parts of South America, where other vegetation is lacking, the stems of columnar cerei, or "cardones," are used for constructing habitations, inclosures, and for timbering mines. Columnar cacti are also planted for living fences, or hedges, especially the "organ cactus" ([[Myrtillocactus geometrizans]]) of tropical Mexico. Leaves are present in nearly all cacti, but in some species they are mere vestiges and can scarcely be seen with the naked eye. In other species they are large and perfectly developed, either with distinct petiole and feather veins, as in Pereshia aculeata, or sessile and fleshy with only the midrib and several parallel nerves apparent as in the genus Pereskiopsis. They are sometimes caducous, fleshy, cylindrical or awl-shaped, as in the genus Opuntia. In the axils of the leaves are peculiar cushion-like areoles (corresponding in all probability to aborted branches) clothed with down or felt-like wool, from which spines, and, in some genera, also flowers, issue. In the genera Opuntia and Pereskiopsis, the areoles also bear minute short barbed bristles called glochidia, which will penetrate the skin and become detached at the slightest contact and are the source of annoying irritation which often persists for many hours.{{SCH}}
  
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The number of genera treated in this work is 35. They are in cultivation in America as odd plants for desert gardens, and as greenhouse curiosities. Many have beautiful showy flowers, those of Cereus grandiflorus (night-blooming cereus) being nearly one foot across, and opening only in the night.
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===Spines===
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[[Image:Cactus1web.jpg|thumb|Many species of cactus have long, sharp [[spine (botany)|spines]].]]
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The spines are not connected with the axis of the stem or branches, but emerge from the areoles. In some forms they are simple and straight, bristle-like, awl-shaped, or short and conical. In others they are bent like fishhooks or are curved and horn-like, with transverse ribs. Sometimes they are minutely downy or hairy and sometimes even plumose or feathery. They may be either naked or enveloped in a membranous barbed sheath. They may be grouped in star-like clusters, with straight or curved rays spreading from a common center, or in comb-like fascicles, with the radial spines arranged in two rows on each side of a longitudinal axis (pectinate). In addition to the radial spines, there are usually erect central spines either straight and rigid, or more or less curved. One of the most striking forms is that of the organ cactus, Myrtillocactus geometrizans, in which the stout erect central spine resembles the blade of a dagger and the radials a guard for the hilt. In contrast with this may be mentioned the spines of Pelecyphora aselliformis, which resemble miniature sow-bugs, or aselli.{{SCH}}
  
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The reader will find the cacti described in this Cyclopedia under the following names: Acanthocereus; Anhalonium = Ariocarpus; Aporocactus: Ariocarpus; Bergerocactus; Cactus; Carnegiea; Cephalocereus; Cereus; Disocactus; Echinocactus; Echinocereus; Echinopsis; Epiphyllum = Zygocactus; Escontria; Hariota; Harrisia; Heliocereus; Hylocereus; Lemaireocereus; Leptocereus; Leuchtenbergia; Lophophora; Mamillaria; Melocactus = Cactus; Myrtillocactus; Nopalea; Opuntia; Pachycereus; Pelecyphora; Pereskia; Pereskiopsis; Phyllocactus = Epiphyllum; Pilocereus = Cephalocereus; Rathbunia; Selenicereus; Schlumbergera; Wilcoxia; Wittia; Zygocactus.
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===Flowers===
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[[Image:Lightmatter cactusflower.jpg|thumb|''[[Echinopsis spachiana]]'' in flower]]
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[[Image:Cactus flower closeup03.jpg|thumb|Closeup image of a cactus flower (''[[Echinopsis spachiana]]'') showing large number of stamens.]]
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The flowers in most cases issue from the upper portion of the areoles, but in certain mamillarias and allied forms they come forth from between the tubercles or from their base at the end of a dorsal groove. Usually the flowers are solitary and sessile, but in the genus Pereskia they are peduncled and often clustered. They may be tinted with rose-color, crimson, purple, yellow or orange, or rarely with copper-color or scarlet, but they are never blue. Often they are pure white at first, gradually becoming suffused with rose-color in age. In a few species they are inconspicuous, as in the epiphytal Rhipsalis. Some are diurnal, others nocturnal; some open at sunrise and close at night or when the sky becomes clouded; others open at a certain hour and close at another fixed hour of the day or night; some last for only a few hours, others for a day, and some persist for several days. Some, like the "night - blooming cereus" are delightfully fragrant, while others are ill-smelling or have no perceptible odor.{{SCH}}
  
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{{SCH}}
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The perianth is not divided sharply into calyx and corolla, although the outer floral leaves are usually sepal-like and the inner ones are true petals. In one great division of the family including Opuntia, which has been named Rotatiflorae, the perianth is more or less wheel- shaped or widely spreading: in the other division. Tubuliflorae, to which Cereus belongs, the floral leaves form a tube, often remarkably long and slender, and crowned with a spreading limb. The floral leaves are not arranged in definite series but somewhat like those of a water-lily, the scale-like lower or outer leaves gradually becoming broad and petaloid as they approach the center. In all cases the perianth crowns the ovary, and sometimes persists after withering on the apex of the fruit. The stamens are very numerous and are inserted on the petals or perianth-tube. The single style is longer and stouter than the slender filaments, and usually terminates into a radially divided stigma. Sometimes the stigma is conspicuously colored and issues star-like from the center of the mass of stamens, as in the genus Echinocereus, in which the emerald-green star contrasts prettily with the golden-yellow or orange-colored stamens, rising from a rosette of rose-purple petals. The ovary, although formed of several carpels, is 1-celled. The placentae are parietal, bearing an indefinite number of ovules, the stalks of which (funiculi) become fleshy as the seeds develop and form a sugary pulp around the seeds.{{SCH}}
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:''This article is about the plant family. For the genus '''Cactus''', see [[Mammillaria]], [[Melocactus]], and [[Opuntia]].''
 
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{{Taxobox
 
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| color = lightgreen or brownish
 
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| name = Cacti
 
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| image = Ferocactus1.jpg
 
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| image_width = 250px
 
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| image_caption = ''[[Ferocactus|Ferocactus pilosus]]'' (Mexican Lime Cactus) growing south of [[Saltillo]], [[Coahuila]], northeast [[Mexico]]
 
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| regnum = [[Plant]]ae
 
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| divisio = [[Flowering plant|Magnoliophyta]]
 
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| classis = [[Dicotyledon|Magnoliopsida]]
 
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| ordo = [[Caryophyllales]]
 
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| familia = '''Cactaceae'''
 
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| familia_authority = [[Antoine Laurent de Jussieu|Juss.]]
 
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| subdivision_ranks = [[Genus|Genera]]
 
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| subdivision =
 
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See [[Taxonomy of the Cactaceae]]
 
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}}
 
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A '''cactus''' (plural '''cactus,''' '''cacti,''' or '''cactuses''') is any member of the [[succulent plant]] family '''Cactaceae'''. They are often used as [[ornamental plant]]s, but some are also [[Crop (agriculture)|crop]] plants.  
 
  
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Cacti are distinctive and unusual plants, which have adapted to extremely [[arid]] and hot [[Natural environment|environment]]s, showing a wide range of [[Anatomy|anatomical]] and [[Physiology|physiological]] features which conserve water. Their stems have expanded into green [[succulent]] structures containing the [[chlorophyll]] necessary for life and growth, while the leaves have become the spines for which cacti are so well known.  
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===Fruits===
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[[Image:Grandjunctionalpineloop 032.jpg|thumb|right| Prickly Pear is among the most common cacti found in North America.]]
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The fruits of the Cactaceae are variable in form. That of the leafy Pereskia is apple-shaped and bears a number of leaf-like bracts on the skin, on which account the fruit of P. aculeata is called blad-appel, or leaf-apple, in the Dutch colonies, while in the British West Indies it is known as Barbados gooseberry and is made into tarts and sauces like real gooseberries. In some of the pereskiopses, the fruit is elongated and shaped like a prickly pear, with watery rind and seeds covered with cottony hairs. In Opuntia and Nopalea the fruit is commonly called prickly pear, or tuna (by the ancient Aztecs, nochtli). These fruits bear small fleshy leaves at first, like the flattened pads of the plants, and when the leaves fall off the areoles persist armed with the irritating sharp-barbed glochidia described above. Many species allied to the genus Cereus bear edible fruits, usually called pitahayas. Those of the tall columnar cardones (Lemaireocereus) are covered with easily detachable tufts of wool and spines but never bear glochidia. Those of Cephalocereus are spineless. The triangular climbing forms which are often trained over garden walls in tropical countries, sometimes bear enormous juicy fruits of fine flavor. Those of Echinocactus are more or less scaly. The fruits of certain species of Echinocereus, called alicoches by the Mexicans, are known to Americans as strawberry cacti, on account of the fine flavor of their juicy pulp. Those of Echinocactus longihamatus are known in northern Mexican markets as limas de viznaga, or cactus limes, on account of their acid taste; and the small smooth crimson fruits of many mamillarias are called chilitos, on account of their resemblance to small chili peppers. Very much like them are the fruits of melon cacti which issue from the dense crown of bristles like scarlet radishes or firecrackers tipped with a fuse. The seeds of the Cactaceae vary considerably in the different groups, and are sometimes useful in making generic determinations. Thus the woolly seeds of Pereskiopsis are sharply distinct from the black glossy seeds of the genus Pereskia, with which the first-named genus was at one time confused. In Opuntia and Nopalea they are flat, hard and bony, somewhat ear-shaped in the flat-jointed opuntias and usually discoid and marginless in cylindrical opuntias. In Cereus they are glossy black, with the testa either quite smooth or minutely pitted; in Echinocereus they are covered with minute tubercles or granules. In Echinocactus, which is not a very homogeneous group, the seeds are pitted in some species and tuberculate in others In one section of Mamillaria (Eumamillaria) they are glossy and marked with sunken rounded pits, while in another section, which should probably be made a distinct genus (Coryphantha) they are frequently smooth. In the closely allied Ariocarpus they are relatively large and tuberculate. In the genus Pelecyphora, they are sometimes kidney-shaped, as in P. aselliformis, and sometimes of a peculiar boat-like form with a very large umbilicus, as in P. pectinata. In the epiphytal Rhipsalis cassytha they are kidney-shaped and finely granular. The seeds of many of the species of Pachycereus ("cardones") are used by the Indians of Lower California and Mexico for food. In southern Puebla the fruit of Pachycereus columnatrajani, called tetezo figs (higos de tetetzo) are a regular food staple, offered for sale in the markets of Tehuacan during the month of May.{{SCH}}
  
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Cacti come in a wide range of shapes and sizes. The tallest is ''[[Pachycereus pringlei]]'', with a maximum recorded height of 19.2 m,<ref>Salak, M. (2000). In search of the tallest cactus. ''Cactus and Succulent Journal'' 72 (3).</ref> and the smallest is ''[[Blossfeldia liliputiana]]'', only about 1 cm diameter at maturity.<ref>[http://www.sbs.utexas.edu/mauseth/ResearchOnCacti/large%20photo%20Blossfeld%20liliput%20plants.htm Mauseth Cactus research: ''Blossfeldia liliputiana'']</ref> Cactus [[flower]]s are large, and like the spines and branches arise from [[areole]]s. Many cactus species are night blooming, as they are [[pollination|pollinated]] by [[nocturnal]] [[insect]]s or small animals, principally moths, bats, and sheep. Cacti's sizes range from small and round to pole-like and tall.
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Other cactus fruits of great economic importance are those of the giant Cereus of our arid southwestern region, [[Carnegiea gigantea]], locally known as pitahayas de sahuara, first brought to notice in the year 1540 by the members of Coronado's expedition. They are not spiny like the fruits of Pachycereus and they burst open when quite ripe. The fruit of [[Lemaireocereus thurberi]], known as pitahaya dulce, although much sweeter, bears clusters of stout spines issuing from tufts of wool. Closely allied to it is [[Lemaireocereus griseus]] of central and southern Mexico, which yields much nutritious fruit. The fruit of the organ cactus, Myrtillocactus geometrizans, sold in the markets as garambullas, either fresh or dried, must also be mentioned as of economic importance.{{SCH}}
  
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Of medicinal importance is the narcotic peyote or "mezcal button" ([[Lophophora williamsii]]), used as an intoxicant and febrifuge by certain tribes of Indians, and regarded by some of them with superstitious reverence. This little plant was regarded by some of the early Spanish writers as a fungus and was used by the Mexican Indians to produce marvelous visions.{{SCH}}
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}}
  
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==Description==
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==Species==
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[[Image:Cactus flower closeup03.jpg|thumb|left|Closeup image of a cactus flower (''[[Echinopsis spachiana]]'') showing large number of stamens.]]
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Selected important genera{{wp}}
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The cacti are succulent plants that grow either as trees, shrubs or in the form of ground cover. Most species grow on the ground, but there is also a whole range of [[epiphytic]] species. In most species, except for the sub-family of the [[Pereskioideae]] (see image), the leaves are greatly or entirely reduced. The flowers, mostly radially symmetrical and hermaphrodite, bloom either by day or by night, depending on species. Their shape varies from tube-like through bell-like to wheel-shaped, and their size from 0.2 to 15-30 metres. Most of them have numerous [[sepal]]s (from 5 to 50 or more), and change form from outside to inside, from [[bract]]s to [[petal]]s. They have [[stamen]]s in great numbers (from 50 to 1,500, rarely fewer). The berry-like fruits may contain few, but mostly many (3,000), seeds, which can be between 0.4 and 12 mm long.<ref>http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=10141 Description of the Family in the Flora of North America.</ref>
 
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The life of a cactus is seldom longer than 300 years, and there are cacti which live only 25 years (although these flower as early as their second year). The Saguaro cactus (''[[Carnegiea gigantea]]'') grows to a height of up to 15 metres (the record is 17 metres 67cm), but in its first ten years it grows only 10 centimetres. The "mother-in-law's cushion" (''[[Echinocactus grusonii]]'') reaches a height of 2.5 meters and a diameter of 1 meter and - at least on the [[Canary Islands|Canaries]] - is already capable of flowering after 6 years. The diameter of cactus flowers ranges from 5 to 30 cm; the colours are often conspicuous and spectacular.
 
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==Taxonomy==
 
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{{seealso|Taxonomy of the Cactaceae}}
 
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The family of the cactaceae, with an age of a few million years, is counted as a relatively young plant family, of which no fossil finds are known. Within this short time span (short at any rate from a geological point of view) the cactuses have undergone a rapid development into extremely specialised plants.
 
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The family of the cactaceae with approx. 2,000-3,000 species and varieties in about 60 genera was originally native to the [[Americas|American]] continent, where their range extends from [[Patagonia]] to the [[Canada|Canadian]]&ndash;[[United States|American]] border. Cactuses inhabit the most diverse regions, from coastal plains to high mountain areas, from the sub-tropics to the deserts. The most dense occurrence of cactuses is to be found in the territories around north [[Mexico]] and the [[Tropic of Cancer|southern tropic]] ([[Argentina]] and [[Bolivia]]). The equivalent plants to cactuses in [[Africa]] and [[Australia]] are representatives of the so-called "other succulents". Occurrences of cactuses outside the Americas are the result of distribution by humans (or in very rare cases by migrating birds).
 
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== Distribution ==
 
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[[Image:Lightmatter cactusflower.jpg|thumb|left|''[[Echinopsis spachiana]]'' in flower]]
 
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Cacti are almost exclusively [[New World]] plants. This means that they are native only in [[North America]], [[South America]], and the [[West Indies]]. There is however one exception, ''[[Rhipsalis baccifera]]''; this species has a [[pantropical]] distribution, occurring in the [[Old World]] tropical [[Africa]], [[Madagascar]] and [[Sri Lanka]] as well as in tropical America. This plant is thought to be a relatively recent colonist in the [[Old World]] (within the last few thousand years), probably carried as [[seed]]s in the [[digestive tract]]s of [[Bird migration|migratory]] [[bird]]s. Many other cacti have become naturalized to similar environments in other parts of the world after being introduced by people.
 
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Cacti are believed to have evolved in the last 30 to 40 million years.  Long ago, the [[Pangaea|Americas were joined to the other continents]], but separated due to [[continental drift]]. Unique species in the New World must have developed after the continents had moved apart. Significant distance between the continents was only achieved in around the last 50 million years. This may explain why cacti are so rare in Africa; the continents had already separated when cacti evolved. Many [[succulent plant]]s in both the Old and New World bear a striking resemblance to cacti, and are often called "cactus" in common usage. This is, however, due to [[parallel evolution]]; none of these are closely related to the Cactaceae.
 
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[[Prickly pear]]s (genus ''[[Opuntia]]'') were imported into [[Australia]] in the [[19th century]] to be used as a natural agricultural fence and to establish an [[Cochineal|cochineal dye]] industry, but quickly became a widespread [[weed]]. This [[invasive species]] is inedible for local [[herbivore]]s and has rendered 40,000 km² of farming land unproductive.
 
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== Adaptations to dry environment ==
 
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Some environments, such as deserts, semi-deserts and dry steppes, receive little water in the form of [[Precipitation (meteorology)|precipitation]]. Plants that inhabit these dry areas are known as [[xerophytes]], and many of them are [[succulent]]s, with thick or reduced, "succulent", [[leaf|leaves]]. Apart from a very few exceptions (for example, the genus "[[Rhodocactus]]") all cactuses are succulent plants, although not all succulent plants are cactuses. Like other [[succulents]], these cacti have a range of specific adaptations that enable them to survive in these environments.
 
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[[Image:Pereskia grandifolia3.jpg|thumb|''Pereskia grandifolia'': ''[[Pereskia]]'' is a weakly succulent genus, which also possesses leaves, and is believed to be very similar to the ancestor of all cacti.]]
 
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Cactus have never lost their leaves completely, they have only reduced its size so that they will reduce the surface area through which water can be lost by transpiration. In some species the leaves are still remarkably large and ordinary while in other species they have became microscopic but they still contain the [[stomata]], [[xylem]] and [[phloem]]. Certain cactus species have also developed [[ephemeral]] leaves, which are leaves that last for a short period of time when the stem is still in his early stages of development. A good example of a species that have ephemeral leaves is the ''Opunta ficus indicia'' better known as the prickly pear. Cactus have also developed [[spine (biology)|spines]] which, in addition to allowing less water to evaporate through [[transpiration]] by shading the plant, as well as to defend the cactus against water-seeking animals. The spines grow from specialized structures called [[areole]]s. Very few members of the family have leaves, and when present these are usually rudimentary and soon fall off; they are typically awl-shaped and only 1-3 mm long. Two genera, ''[[Pereskia]]'' and ''[[Pereskiopsis]]'', do however retain large, non-succulent leaves 5-25 cm long, and also non-succulent stems. ''Pereskia'' has now been determined to be the ancestral genus from which all other cacti evolved.<ref>http://www.eurekalert.org/pub_releases/2006-05/uocp-hdc051206.php</ref>
 
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[[Image:Cactus1web.jpg|thumb|left|Many species of cactus have long, sharp [[spine (botany)|spines]].]]
 
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Enlarged [[Plant stem|stems]] carry out [[photosynthesis]] and store water. Unlike many other succulents, the stem is the only part of a true cactus where this takes place.  Much like many other plants that have [[wax]]y coatings on their leaves, Cacti often have a waxy coating on their stems to prevent water loss. This works by preventing water from spreading on the surface and allowing water to trickle down the stem to be absorbed by the roots and used for photosynthesis.
 
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The bodies of many cacti have become thickened during the course of evolution, and form water-retentive tissue and in many cases assume the optimal shape of the sphere (combining highest possible volume with lowest possible surface area). By reducing its surface area, the body of the plant is also protected against excessive sunlight.
 
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[[Image:Cactus_arizona.jpg|thumb|right|[[Saguaro]] cactus in [[Arizona]], USA. This species is well known from [[Western (genre)|Western films]].]]
 
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Most cactuses have a short [[growing season]] and long dormancy. For example, a fully-grown Saguaro cactus ''([[Carnegiea gigantea]])'' can absorb up to 3,000 litres of water in ten days. This is helped by cacti's ability to form new roots quickly. Only two hours after rain after a relatively long drought the formation of new roots begins. Apart from a few exceptions an extensively ramified root system is formed, which spreads out immediately beneath the surface. The salt concentration in the root cells is relatively high, so that when moisture is encountered, water can immediately be absorbed in the greatest possible quantity.
 
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But the plant body itself is also capable of absorbing moisture (through the epidermis and the thorns), which for plants that are exposed to moisture almost entirely, or indeed in some cases solely, in the form of fog, is of the greatest importance for sustaining life.
 
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Most cacti have very shallow roots that can spread out widely close to the surface of the ground to collect water, an adaptation to infrequent rains; in one examination, a young [[Saguaro]] only 12 cm tall had a root system covering an area 2 meters in diameter, but with no roots more than 10 cm deep.<ref name="dalhousie">[http://cactus.biology.dal.ca/biology.html Dalhousie University: Biology of Cacti]</ref> The larger columnar cacti also develop a [[taproot]], primarily for anchoring but also to reach deeper water supplies and mineral nutrients.<ref name="dalhousie"/>
 
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One feature distinguishes the cactuses from all other plants: cactuses possess ''[[areole]]s'', as they are known. The areole appears like a cushion with a diameter of up to 15 mm and is formed by two opposing buds in the angles of a leaf. From the upper bud develops either a blossom or a side shoot, from the lower bud develop thorns. The two buds of the areoles can lie very close together, but they can also sometimes be separated by several centimetres.
 
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Like other succulents in the families of the [[Crassulaceae]], [[Agavaceae]] (agaves), [[Euphorbiaceae]] (euphorbias), [[Liliaceae]] (lilies), [[Orchidaceae]] (orchids) and [[Vitaceae]] (vines), cacti reduce water loss through transpiration by [[Crassulacean acid metabolism]].<ref name="dalhousie"/> Here, transpiration does not take place during the day at the same time as [[photosynthesis]], but at night. The plant stores the [[carbon dioxide]] chemically linked to [[malic acid]] until the daytime. During the day the [[stoma]]ta are closed and the plant releases the stored CO<sub>2</sub> and uses it for photosynthesis. Because transpiration takes place during the cool humid night hours, water loss through transpiration is significantly reduced.
 
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==Reproductive ecology==
 
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[[Image:Echinopsis - Blüte von der Seite.jpg|thumb|left|Blooming ''[[Echinopsis]]''. The sweet-smelling flower opens towards evening and dies the following morning.]]
 
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Some cactus flowers form long tubes (up to 30 centimetres) so that only moths can reach the nectar and thus pollinate the blossoms. There are also specialisations for [[bat]]s, [[humming bird]]s and particular species of [[bee]]s. The duration of flowering is very variable. Many flowers, for example those of ''[[Selenicereus grandiflorus]]'' (''Queen of the Night'') are only fully open for two hours at night. Other cactuses flower for a whole week. Most cactuses are [[Self-incompatibility in plants|self-incompatible]], and thus require a pollinator. A few are [[autogamy|autogamous]] and are able to pollinate themselves. [[Frailea]]s only opens their flowers completely in exceptional circumstances; they mostly pollinate themselves with their flowers closed ("cleistogamy"). The flower itself has also undergone a further development: the [[ovary (plants)|ovary]] tends to become a completely protected area, protected by thorns, hairs and scales. Seed formation is very prolific, and the fruits are mostly fleshy, pleasant tasting and conspicuously coloured. Goats, birds, ants, mice and bats contribute significantly to the spreading of the seeds.
 
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Because of the plants' high water-retention ability, detached parts of the plant can survive for long periods and are able to grow new roots everywhere on the plant body.
 
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Some cacti are able to reproduce by budding. These cacti grow on one another. While they appear to be one plant they are actually several cacti. These types of cacti will survive if separated from the main plant. They will take root and start the budding process as the main plant.
 
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==History==
 
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[[Image:Carl Spitzweg 027.jpg|thumb|[[Carl Spitzweg]]: The Cactus Lover, c. 1856]]
 
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Among the remains of the [[Aztec]] civilization cactuses can be found repeatedly in pictorial representations, sculpture and drawings, principally ''[[Echinocactus grusonii]]''. This cactus, also known as "Mother-in-law's Cushion", has great ritual significance - human sacrifices were carried out on these cactuses. [[Tenochtitlan]] (the earlier name of [[Mexico City]]) means "place of the sacred cactus". The national arms of Mexico to this day show the eagle, snake and cactus.
 
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Economic exploitation of the cactus can also be traced back to the Aztecs. The [[North American Indian]]s exploits the [[alkaloid]] content of many cactuses for ritual purposes. Today, besides their use as foodstuffs (jam, fruit, vegetables), their principal use is as a host for the [[cochineal]] insect, from which a red dye ([[carmine]])is obtained which is used in [[Campari]] or high-quality [[lipstick]]s. Particularly in [[South America]] dead pillar cactuses yield valuable wood for construction. Some cactuses are also of pharmaceutical significance.
 
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From the moment of their discovery by early European explorers cactuses have aroused much interest: [[Christopher Columbus]] brought the first [[melocactus]]es to Europe. Scientific interest in them began in the 17th century. By 1737 24 species were know
 
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n, which [[Linné]] grouped together as the genus "Cactus". With the passage of time cactuses enjoyed increasing popularity: sometimes they were of scientific interest only; at other times as fashionable plants they enjoyed a real boom.
 
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From the beginning of the 20th century interest in cactuses has increased steadily, interrupted only by the two world wars. This was accompanied by a rising commercial interest, the negative consequences of which culminated in raids on the cactuses' native habitats, resulting in the extermination of many species. Through the great number of cactus admirers, whether their interest is scientific or hobby-oriented, new species and varieties are even today discovered every year.
 
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All cactuses are covered by the [[Convention on International Trade in Endangered Species of Wild Fauna and Flora]], and many species by virtue of their inclusion in Appendix 1 are fully protected.
 
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Some countries have a rather contradictory attitude to species protection. In Mexico for example to be caught in the act of digging up cactuses carries a prison sentence, but cactus habitats are destroyed for the construction of new roads and electricity lines. To be borne in mind here is that some cactus habitats have a total area of no more than 1,000 square metres.{{Fact|date=February 2007}}{{dubious}} If this habitat is destroyed, either by construction or by plundering, the species growing there is lost for posterity if it is endemic (ie, growing in that one spot and nowhere else).
 
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== Uses ==
 
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[[Image:Echinocactus grusonii kew.jpg|thumb|left|''[[Echinocactus grusonii]]'' is a popular species in cultivation]]
 
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Cacti, cultivated by people worldwide, are a familiar sight as potted plants, [[houseplant]]s or in ornamental gardens in warmer climates. They often form part of [[xeriscaping|xerophilic (dry) gardens]] in arid regions, or raised rockeries. Some countries, such as Australia, have water restrictions in many cities, so drought-resistant plants are increasing in popularity. Numerous species have entered widespread cultivation, including members of ''[[Echinopsis]]'', ''[[Mammillaria]]'' and ''[[Cereus]]'' among others. Some, such as the Golden Barrel Cactus, ''[[Echinocactus grusonii]]'', are prominent in garden design. Cacti are commonly used for fencing material where there is a lack of either natural resources or financial means to construct a permanent fence. This is often seen in arid and warm climates, such as the [[Masai Mara]] in Kenya. This is known as a [[cactus fence]].
 
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As well as garden plants, many cacti have important commercial uses; some cacti bear edible [[fruit]], such as the [[opuntia|prickly pear]] and ''[[Hylocereus]]'', which produces [[Dragon fruit]] or [[Pitaya]]. ''[[Opuntia]]'' are also used as host plants for cochineal bugs in the [[cochineal]] dye industry in [[Central America]].
 
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The [[Peyote]], ''Lophophora williamsii'', is a well-known psychoactive agent used by Native Americans in the Southwest of the [[United States of America]]. Some species of ''[[Echinopsis]]'' (previously ''[[Trichocereus]]'') also have psychoactive properties.
 
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==Etymology==
 
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[[Image:Grandjunctionalpineloop 032.jpg|thumb|right| Prickly Pear is among the most common cacti found in North America.]]
 
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The word ''cactus'' is ultimately derived from [[Ancient Greek|Greek]] Κακτος ''kaktos'', used in classical Greek for a species of spiny [[thistle]], possibly the [[cardoon]], and used as a generic name, ''Cactus'', by [[Carolus Linnaeus|Linnaeus]] in 1753 (now rejected in favour of ''[[Mammillaria]]''). There is some dispute as to the proper plural form of the word; as a Greek loan into English, the correct plural in English would be "cactuses". However, as a word in [[Botanical Latin]] (as distinct from [[Classical Latin]]), "cactus" would follow standard Latin rules for pluralization and become "cacti", which has become the prevalent usage in English.  Regardless, ''cactus'' is popularly used as both singular and plural, and is cited as both singular and plural by the ''Random House Unabridged Dictionary'' (2006).
 
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==Selected important genera==
 
 
:''For a full list see [[Taxonomy of the Cactaceae]]''
 
:''For a full list see [[Taxonomy of the Cactaceae]]''
 
{|
 
{|
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*''[[Weberocereus]]''
 
*''[[Weberocereus]]''
 
*''[[Yungasocereus]]''
 
*''[[Yungasocereus]]''
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|}
  
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==Gallery==
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{{photo-sources}}<!-- remove this line if there are already 3 or more photos in the gallery  -->
  
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<gallery>
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Image:Echinopsis - Blüte von der Seite.jpg|Blooming ''[[Echinopsis]]''. The sweet-smelling flower opens towards evening and dies the following morning.
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Image:Ferocactus1.jpg| ''[[Ferocactus|Ferocactus pilosus]]'' (Mexican Lime Cactus)
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Image:Upload.png| photo 2
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Image:Upload.png| photo 3
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</gallery>
  
 
==References==
 
==References==
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{{commons|Cactaceae}}
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*[[Standard Cyclopedia of Horticulture]], by L. H. Bailey, MacMillan Co., 1963
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<div class="references-small"><references /></div>
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<!--- xxxxx  *Flora: The Gardener's Bible, by Sean Hogan. Global Book Publishing, 2003. ISBN 0881925381  -->
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* Anderson, E. F. (2001). ''The Cactus Family''. Timber Press ISBN 0-88192-498-9 - Comprehensive and lavishly illustrated.
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<!--- xxxxx  *American Horticultural Society: A-Z Encyclopedia of Garden Plants, by Christopher Brickell, Judith D. Zuk. 1996. ISBN 0789419432  -->
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* Benson, L. (1981). ''The Cacti of Arizona''. University of Arizona Press ISBN 0-8165-0509-8 - Thorough treatment of the Arizona, U.S.A., species
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<!--- xxxxx  *Sunset National Garden Book. Sunset Books, Inc., 1997. ISBN 0376038608  -->
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* Kiesling, R., Mauseth, J. D., & Ostolaza, C. N. (2002). ''A Cactus Odyssey''. Timber Press ISBN 0-88192-526-8
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* http://www.kaktusrehberi.com/ many photos,morphology,Propagation,
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==See also==
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*[[Succulents]]
  
 
==External links==
 
==External links==
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* [http://www.floridanaturepictures.com/cacti/cacti.html Cacti Picture Gallery]
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*{{wplink}}
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* [http://www.cactiguide.com/ CactiGuide - many photos, and discussion forum]
 
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* [http://www.rhipsalis.com/maxwell3.htm  The Rhipsalis Riddle]
 
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* http://www.kaktusrehberi.com/ many photos,morphology,Propagation
 
  
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{{stub}}
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[[Category:Categorize]]
 
[[Category:Cacti| ]]
 
[[Category:Cacti| ]]
 
[[Category:Plant families]]
 
[[Category:Plant families]]
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Latest revision as of 17:02, 29 May 2009


Echinocactus grusonii is a popular species in cultivation


Plant Characteristics
Cultivation
Sunset Zones: see genus/species
Scientific Names

Cactaceae >



Read about Cactus in the Standard Cyclopedia of Horticulture 

Cactus or cacti. The plants correctly designated by this name constitute the family Cactaceae. Scarcely any group in the whole plant kingdom is more remarkable for its strange and varied forms, the beauty of its flowers, and wonderful adaptation to desert life. It is not, however, confined to desert regions; for in the moist forests of the tropics of the New World it is represented by a number of interesting forms often epiphytal or scrambling in their habit of growth, with beautiful flowers and sometimes with delicious edible fruit.CH

Range

The Cactaceae are confined to America, the only apparent exception being the genus Rhipsalis, composed of plants with the habits of the mistletoe, growing on the trunks and branches of trees, and bearing small pellucid glutinous berries. This genus, endemic in tropical America, has found its way to Africa, the island of Mauritius and even to Ceylon; and several opuntias, or prickly pears, occur on the shores of the Mediterranean, in South Africa, and Australia, where they have made themselves so thoroughly at home as to be regarded by many writers as indigenous. The Cactaceae are not confined to tropical or even semi-tropical regions. At least two species of Opuntia extend northward into British Columbia, and species of Echinocereus, Echinocactus, and Mamillaria are found in the state of Colorado. The xerophytic forms flourish especially in the southwestern United States, the Mexican plateau, the peninsula of Lower California, where there are great cactus forests, and the vicinity of Tehuacan, in the southern part of the Mexican state of Puebla, a region celebrated for its remarkable and gigantic tree-like forms related to the genus Cereus.CH

To the southward, the family extends to Chile and Argentina. Giant torch thistles and echinocacti are scattered over the pampas of Uruguay, and melon-shaped echinopses amid the snows of the lofty plateau of Bolivia.CH

The genus Mamillaria, so well represented in the southwestern United States and Mexico, is almost absent from Central America, the representative genera of that region as well as of the warm Huasteca region of eastern Mexico being Cereus, Pereskia, Pereskiopsis, Nopalea, and Opuntia; while the "turk's-head” or "melon cacti" are chiefly West Indian.CH

Structure

Saguaro cactus in Arizona, USA. This species is well known from Western films.
Pereskia grandifolia: Pereskia is a weakly succulent genus, which also possesses leaves, and is believed to be very similar to the ancestor of all cacti.

The peculiar structure of columnar, opuntioid, and melon-shaped cacti is undoubtedly the result of excessive dryness of the climates in which they occur, to protect themselves from which they have been obliged to store up water and to reduce their transpiration as low as possible. They have a more or less pronounced woody axis surrounded by pulpy cellular tissue (parenchyma) in which the water-supply is stored. The stomata are usually situated in depressions or grooves in the leathery cuticle; and as an additional means for checking transpiration, the cell-sap is nearly always mucilaginous, while in some forms latex cells are present, filled with milky or gummy fluid which hardens on exposure to the air and effectively heals wounds in the soft fleshy plant. Certain species of Echinocactus (viznagas) are like great barrels studded with spines and filled with pulp of the consistency of watermelon rind, which is sometimes made into conserves like citron (dulces de viznaga). Other forms, like species of Pereskia, Pereskiopsis, and arboreous opuntias have hard, woody stems and branches. The reticulated skeletons of certain species of opuntia are manufactured into walking-sticks, legs of furniture, napkin rings, and even into veneering for woodwork. In Lower California and some parts of South America, where other vegetation is lacking, the stems of columnar cerei, or "cardones," are used for constructing habitations, inclosures, and for timbering mines. Columnar cacti are also planted for living fences, or hedges, especially the "organ cactus" (Myrtillocactus geometrizans) of tropical Mexico. Leaves are present in nearly all cacti, but in some species they are mere vestiges and can scarcely be seen with the naked eye. In other species they are large and perfectly developed, either with distinct petiole and feather veins, as in Pereshia aculeata, or sessile and fleshy with only the midrib and several parallel nerves apparent as in the genus Pereskiopsis. They are sometimes caducous, fleshy, cylindrical or awl-shaped, as in the genus Opuntia. In the axils of the leaves are peculiar cushion-like areoles (corresponding in all probability to aborted branches) clothed with down or felt-like wool, from which spines, and, in some genera, also flowers, issue. In the genera Opuntia and Pereskiopsis, the areoles also bear minute short barbed bristles called glochidia, which will penetrate the skin and become detached at the slightest contact and are the source of annoying irritation which often persists for many hours.CH

Spines

Many species of cactus have long, sharp spines.

The spines are not connected with the axis of the stem or branches, but emerge from the areoles. In some forms they are simple and straight, bristle-like, awl-shaped, or short and conical. In others they are bent like fishhooks or are curved and horn-like, with transverse ribs. Sometimes they are minutely downy or hairy and sometimes even plumose or feathery. They may be either naked or enveloped in a membranous barbed sheath. They may be grouped in star-like clusters, with straight or curved rays spreading from a common center, or in comb-like fascicles, with the radial spines arranged in two rows on each side of a longitudinal axis (pectinate). In addition to the radial spines, there are usually erect central spines either straight and rigid, or more or less curved. One of the most striking forms is that of the organ cactus, Myrtillocactus geometrizans, in which the stout erect central spine resembles the blade of a dagger and the radials a guard for the hilt. In contrast with this may be mentioned the spines of Pelecyphora aselliformis, which resemble miniature sow-bugs, or aselli.CH

Flowers

Echinopsis spachiana in flower
Closeup image of a cactus flower (Echinopsis spachiana) showing large number of stamens.

The flowers in most cases issue from the upper portion of the areoles, but in certain mamillarias and allied forms they come forth from between the tubercles or from their base at the end of a dorsal groove. Usually the flowers are solitary and sessile, but in the genus Pereskia they are peduncled and often clustered. They may be tinted with rose-color, crimson, purple, yellow or orange, or rarely with copper-color or scarlet, but they are never blue. Often they are pure white at first, gradually becoming suffused with rose-color in age. In a few species they are inconspicuous, as in the epiphytal Rhipsalis. Some are diurnal, others nocturnal; some open at sunrise and close at night or when the sky becomes clouded; others open at a certain hour and close at another fixed hour of the day or night; some last for only a few hours, others for a day, and some persist for several days. Some, like the "night - blooming cereus" are delightfully fragrant, while others are ill-smelling or have no perceptible odor.CH

The perianth is not divided sharply into calyx and corolla, although the outer floral leaves are usually sepal-like and the inner ones are true petals. In one great division of the family including Opuntia, which has been named Rotatiflorae, the perianth is more or less wheel- shaped or widely spreading: in the other division. Tubuliflorae, to which Cereus belongs, the floral leaves form a tube, often remarkably long and slender, and crowned with a spreading limb. The floral leaves are not arranged in definite series but somewhat like those of a water-lily, the scale-like lower or outer leaves gradually becoming broad and petaloid as they approach the center. In all cases the perianth crowns the ovary, and sometimes persists after withering on the apex of the fruit. The stamens are very numerous and are inserted on the petals or perianth-tube. The single style is longer and stouter than the slender filaments, and usually terminates into a radially divided stigma. Sometimes the stigma is conspicuously colored and issues star-like from the center of the mass of stamens, as in the genus Echinocereus, in which the emerald-green star contrasts prettily with the golden-yellow or orange-colored stamens, rising from a rosette of rose-purple petals. The ovary, although formed of several carpels, is 1-celled. The placentae are parietal, bearing an indefinite number of ovules, the stalks of which (funiculi) become fleshy as the seeds develop and form a sugary pulp around the seeds.CH

Fruits

Prickly Pear is among the most common cacti found in North America.

The fruits of the Cactaceae are variable in form. That of the leafy Pereskia is apple-shaped and bears a number of leaf-like bracts on the skin, on which account the fruit of P. aculeata is called blad-appel, or leaf-apple, in the Dutch colonies, while in the British West Indies it is known as Barbados gooseberry and is made into tarts and sauces like real gooseberries. In some of the pereskiopses, the fruit is elongated and shaped like a prickly pear, with watery rind and seeds covered with cottony hairs. In Opuntia and Nopalea the fruit is commonly called prickly pear, or tuna (by the ancient Aztecs, nochtli). These fruits bear small fleshy leaves at first, like the flattened pads of the plants, and when the leaves fall off the areoles persist armed with the irritating sharp-barbed glochidia described above. Many species allied to the genus Cereus bear edible fruits, usually called pitahayas. Those of the tall columnar cardones (Lemaireocereus) are covered with easily detachable tufts of wool and spines but never bear glochidia. Those of Cephalocereus are spineless. The triangular climbing forms which are often trained over garden walls in tropical countries, sometimes bear enormous juicy fruits of fine flavor. Those of Echinocactus are more or less scaly. The fruits of certain species of Echinocereus, called alicoches by the Mexicans, are known to Americans as strawberry cacti, on account of the fine flavor of their juicy pulp. Those of Echinocactus longihamatus are known in northern Mexican markets as limas de viznaga, or cactus limes, on account of their acid taste; and the small smooth crimson fruits of many mamillarias are called chilitos, on account of their resemblance to small chili peppers. Very much like them are the fruits of melon cacti which issue from the dense crown of bristles like scarlet radishes or firecrackers tipped with a fuse. The seeds of the Cactaceae vary considerably in the different groups, and are sometimes useful in making generic determinations. Thus the woolly seeds of Pereskiopsis are sharply distinct from the black glossy seeds of the genus Pereskia, with which the first-named genus was at one time confused. In Opuntia and Nopalea they are flat, hard and bony, somewhat ear-shaped in the flat-jointed opuntias and usually discoid and marginless in cylindrical opuntias. In Cereus they are glossy black, with the testa either quite smooth or minutely pitted; in Echinocereus they are covered with minute tubercles or granules. In Echinocactus, which is not a very homogeneous group, the seeds are pitted in some species and tuberculate in others In one section of Mamillaria (Eumamillaria) they are glossy and marked with sunken rounded pits, while in another section, which should probably be made a distinct genus (Coryphantha) they are frequently smooth. In the closely allied Ariocarpus they are relatively large and tuberculate. In the genus Pelecyphora, they are sometimes kidney-shaped, as in P. aselliformis, and sometimes of a peculiar boat-like form with a very large umbilicus, as in P. pectinata. In the epiphytal Rhipsalis cassytha they are kidney-shaped and finely granular. The seeds of many of the species of Pachycereus ("cardones") are used by the Indians of Lower California and Mexico for food. In southern Puebla the fruit of Pachycereus columnatrajani, called tetezo figs (higos de tetetzo) are a regular food staple, offered for sale in the markets of Tehuacan during the month of May.CH

Other cactus fruits of great economic importance are those of the giant Cereus of our arid southwestern region, Carnegiea gigantea, locally known as pitahayas de sahuara, first brought to notice in the year 1540 by the members of Coronado's expedition. They are not spiny like the fruits of Pachycereus and they burst open when quite ripe. The fruit of Lemaireocereus thurberi, known as pitahaya dulce, although much sweeter, bears clusters of stout spines issuing from tufts of wool. Closely allied to it is Lemaireocereus griseus of central and southern Mexico, which yields much nutritious fruit. The fruit of the organ cactus, Myrtillocactus geometrizans, sold in the markets as garambullas, either fresh or dried, must also be mentioned as of economic importance.CH

Of medicinal importance is the narcotic peyote or "mezcal button" (Lophophora williamsii), used as an intoxicant and febrifuge by certain tribes of Indians, and regarded by some of them with superstitious reverence. This little plant was regarded by some of the early Spanish writers as a fungus and was used by the Mexican Indians to produce marvelous visions.CH


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


Species

Selected important generawp

For a full list see Taxonomy of the Cactaceae

Gallery

If you have a photo of this plant, please upload it! Plus, there may be other photos available for you to add.

  • Blooming Echinopsis. The sweet-smelling flower opens towards evening and dies the following morning.

  • Ferocactus pilosus (Mexican Lime Cactus)

  • photo 2

  • photo 3

References

See also

External links


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