วันเสาร์ที่ 23 กุมภาพันธ์ พ.ศ. 2551

A rose is a flowering shrub of the genus Rosa, and the flower of this shrub.[1][2] There are more than a hundred species of wild roses, all from the northern hemisphere and mostly from temperate regions. The species form a group of generally prickly shrubs or climbers, and sometimes trailing plants, reaching 2–5 metres tall, occasionally reaching as high as 20 metres by climbing over other plants.[3]
The name originates from Latin rosa, borrowed through Oscan from colonial Greek in southern Italy: rhodon (Aeolic form: wrodon), from Aramaic wurrdā, from Assyrian wurtinnu, from Old Iranian *warda (cf. Armenian vard, Avestan warda, Sogdian ward, Parthian wâr).[4][5][6]
Rose hips are sometimes eaten, mainly for their vitamin C content. They are usually pressed and filtered to make rose hip syrup, as the fine hairs surrounding the seeds are unpleasant to eat (resembling itching powder). They can also be used to make herbal tea, jam, jelly and marmalade. A rose that has aged or gone rotten may not be particularly fragrant, but the rose's basic chemistry prevents it from producing a pungent odor of any kind. Notably, when balled and mashed together the fragrance of the rose is enhanced.[7] The fragrance of particularly large balls of mashed roses is enhanced even further. Rose hips are also used to produce an oil used in skin products. Rose shrubs are often used by homeowners and landscape architects for home security purposes. The sharp thorns of many rose species deter unauthorized persons from entering private properties, and may prevent break-ins if planted under windows and near drainpipes. The aesthetic characteristics of rose shrubs, in conjunction with their home security qualities, makes them a considerable alternative to artificial fences and walls.[1][2]
Contents[hide]
1 Botany
1.1 Species
2 Pests and diseases
3 Cultivation
4 Pruning
4.1 Deadheading
5 History
6 Culture
6.1 Symbolism
6.2 In art
6.3 Quotes
7 Perfume
8 Notable rose growers
8.1 Rose Capital of America
8.2 Individuals
9 Notes
10 See also

Botany

Rosa canina hips
The
leaves of most species are 5–15 centimetres long, pinnate, with (3–) 5–9 (–13) leaflets and basal stipules; the leaflets usually have a serrated margin, and often a few small prickles on the underside of the stem. The vast majority of roses are deciduous, but a few (particularly in Southeast Asia) are evergreen or nearly so.
The
flowers of most species roses have five petals, with the exception of Rosa sericea, which usually has only four. Each petal is divided into two distinct lobes and is usually white or pink, though in a few species yellow or red. Beneath the petals are five sepals (or in the case of some Rosa sericea, four). These may be long enough to be visible when viewed from above and appear as green points alternating with the rounded petals. The ovary is inferior, developing below the petals and sepals.
The
aggregate fruit of the rose is a berry-like structure called a rose hip. Rose species that produce open-faced flowers are attractive to pollinating bees and other insects, thus more apt to produce hips. Many of the domestic cultivars are so tightly petalled that they do not provide access for pollination. The hips of most species are red, but a few (e.g. Rosa pimpinellifolia) have dark purple to black hips. Each hip comprises an outer fleshy layer, the hypanthium, which contains 5–160 "seeds" (technically dry single-seeded fruits called achenes) embedded in a matrix of fine, but stiff, hairs. Rose hips of some species, especially the Dog Rose (Rosa canina) and Rugosa Rose (Rosa rugosa), are very rich in vitamin C, among the richest sources of any plant. The hips are eaten by fruit-eating birds such as thrushes and waxwings, which then disperse the seeds in their droppings. Some birds, particularly finches, also eat the seeds.
While the sharp objects along a rose stem are commonly called "thorns", they are actually prickles — outgrowths of the epidermis (the outer layer of tissue of the stem). True thorns, as produced by e.g.
Citrus or Pyracantha, are modified stems, which always originate at a node and which have nodes and internodes along the length of the thorn itself. Rose prickles are typically sickle-shaped hooks, which aid the rose in hanging onto other vegetation when growing over it. Some species such as Rosa rugosa and R. pimpinellifolia have densely packed straight spines, probably an adaptation to reduce browsing by animals, but also possibly an adaptation to trap wind-blown sand and so reduce erosion and protect their roots (both of these species grow naturally on coastal sand dunes). Despite the presence of prickles, roses are frequently browsed by deer. A few species of roses only have vestigial prickles that have no points.

Species
Further information: List of Rosa species

Rosa multiflora
Some representative rose species
Rosa canina — Dog Rose, Briar Bush
Rosa chinensis — China Rose
Rosa dumalis — Glaucous Dog Rose
Rosa gallica — Gallic Rose, French Rose
Rosa gigantea (syn. R. x odorata gigantea)
Rosa glauca (syn. R. rubrifolia) — Redleaf Rose
Rosa laevigata (syn. R. sinica) — Cherokee Rose, Camellia Rose, Mardan Rose
Rosa multiflora — Multiflora Rose
Rosa persica (syn. Hulthemia persica, R. simplicifolia)
Rosa roxburghii — Chestnut Rose, Burr Rose
Rosa rubiginosa (syn. R. eglanteria) — Eglantine, Sweet Brier
Rosa rugosa — Rugosa Rose, Japanese Rose
Rosa spinosissima — Scotch Rose
Rosa stellata — Gooseberry Rose, Sacramento Rose
Rosa virginiana (syn. R. lucida) — Virginia Rose

Pests and diseases
Main articles: Pests and diseases of roses and List of rose diseases
Roses are subject to several diseases. The most serious is rose rust (Phragmidium mucronatum), a species of rust fungus, which can defoliate the plant. More common, though less debilitating, are rose black spot, caused by the fungus Diplocarpon rosae, which makes circular black spots on the leaves in summer, and powdery mildew, caused by Sphaerotheca pannosa. Fungal diseases are best solved by a preventative fungicidal spray program rather than by trying to cure an infection after it is visible. After the disease is visible, its spread can be minimized through pruning and use of fungicides although actual infection cannot be reversed. Some rose varieties are considerably less susceptible than others to fungal disease.
The main insect pest affecting roses is the
aphid (greenfly), which sucks the sap and weakens the plant. Ladybirds are a predator of aphids and should be encouraged in the rose garden. Spraying with insecticide is often recommended but should be done with care to minimize loss of beneficial insects. Roses are also used as food plants by the larvae of some Lepidoptera species; see list of Lepidoptera that feed on roses.

Cultivation
See also: Rose cultivars named after celebrities

Rose-picking in the Rose Valley near the town of Kazanlak in Bulgaria, 1870s, engraving by Austro-Hungarian traveller F. Kanitz

Rosa x alba 'Alba Semiplena', an Alba rose

Rosa 'Maiden's Blush', an Alba rose

'Rosa 'Zéphirine Drouhin', a Bourbon rose

Rosa 'Cajun Sunrise', a modern Hybrid Tea rose

Rosa 'Borussia', a modern Floribunda rose

Rosa 'Climbing Souvenir de la Malmaison', a Bourbon rose
Roses are one of the most popular garden shrubs, as well as the most popular and commonly sold florists' flowers. In addition to their great economic importance as a florists crop, roses are also of great value to the perfume industry.
Many thousands of rose hybrids and cultivars have been bred and selected for garden use, mostly double-flowered with many or all of the stamens mutated into additional petals. As long ago as 1840 a collection numbering over one thousand different cultivars, varieties and species was possible when a rosarium was planted by Loddiges nursery for Abney Park Cemetery, an early Victorian garden cemetery and arboretum in England. Twentieth-century rose breeders generally emphasized size and color, producing large, attractive blooms with little or no scent. Many wild and "old-fashioned" roses, by contrast, have a strong sweet scent.
Roses thrive in temperate climates, though certain species and cultivars can flourish in sub-tropical and even tropical climates, especially when grafted onto appropriate rootstock.
There is no single system of classification for garden roses. In general, however, roses are placed in one of three main groups:
Wild Roses — The wild roses includes the species listed above and some of their hybrids.
Old Garden Roses — Most Old Garden Roses are classified into one of the following groups. In
general, Old Garden Roses of European or Mediterranean origin are once-blooming shrubs, with notably fragrant, double-flowered blooms primarily in shades of white, pink and red. The shrubs' foliage tends to be highly disease-resistant, and they generally bloom only on two-year-old canes.
Alba — Literally "white roses", derived from R. arvensis and the closely allied R. alba. These are
some of the oldest garden roses, probably brought to Great Britain by the Romans. The shrubs flower once yearly in the spring with blossoms of white or pale pink. The shrubs frequently feature gray-green foliage and a climbing habit of growth . Examples: 'Alba Semiplena', 'White Rose of York'.
GallicaThe gallica roses have been developed from R. gallica, which is a native of central and southern Europe. They flower once in the summer over low shrubs rarely over 4' tall. Unlike most other once-blooming Old Garden Roses, the gallica class includes shades of red, maroon and deep purplish crimson. Examples: 'Cardinal de Richelieu', 'Charles de Mills', 'Rosa Mundi' (R. gallica versicolor).
DamaskRobert de Brie is given credit for bringing them from Persia to Europe sometime between 1254 and 1276, although there is evidence from ancient Roman frescoes that at least one damask rose, the Autumn Damask, existed in Europe for hundreds of years prior. Summer damasks (crosses between gallica roses and R. phoenicea) bloom once in summer. Autumn damasks (Gallicas crossed with R. moschata) bloom again later, in the autumn. Shrubs tend to have rangy to sprawly growth habits and vicious thorns. The flowers typically have a more loose petal formation than gallicas, as well as a stronger, tangy fragrance. Examples: 'Ispahan', 'Madame Hardy'.
Centifolia (or Provence) — These roses, raised in the seventeenth century in the Netherlands, are named for their "one hundred" petals; they are often called "cabbage" roses due to the globular shape of the flowers. The result of damask roses crossed with albas, the centifolias are all once-flowering. As a class, they are notable for their inclination to produce mutations of various sizes and forms, including moss roses and some of the first miniature roses (see below) . Examples: 'Centifolia', 'Paul Ricault'.
Moss — Mutations of primarily centifolia roses (or sometimes damasks), these have a mossy
excrescence on the stems and sepals that often emits a pleasant woodsy or balsam scent when rubbed. Moss roses are cherised for this unique trait, but as a group they have contributed nothing to the development of new rose classifications. Moss roses with centifolia background are once-flowering; some moss roses exhibit repeat-blooming, indicative of Autumn Damask parentage. Example: 'Common Moss' (centifolia-moss), 'Alfred de Dalmas' (Autumn Damask moss).
ChinaThe China roses were grown in East Asia for thousands of years and finally reached Western Europe in the late 1700s. Compared to the aforementioned European rose classes, the China roses had smaller, less fragrant, more poorly formed blooms carried over twiggier, more cold-sensitive shrubs. Yet they possessed the amazing ability to bloom repeatedly throughout the summer and into late autumn, unlike their European counterparts. This made them highly desirable for hybridization purposes in the early 1800s. The flowers of China roses were also notable for their tendency to "suntan," or darken over time — unlike the blooms of European roses, which tended to fade after opening. Four China roses ('Slater's Crimson China', 1792; 'Parsons' Pink China', 1793; 'Hume's Blush China', 1809; and 'Parks' Yellow Tea Scented China', 1824) were brought to Europe in the late eighteenth and early nineteenth centuries. This brought about the creation of the first classes of repeat-flowering Old Garden Roses, and later the Modern Garden Roses. Examples: 'Old Blush China', 'Mutabilis'.
PortlandThe Portland roses represent the first group of crosses between China roses and European roses, specifically gallicas and damasks. They were named after the Duchess of Portland who received (from Italy in 1800) a rose then known as R. paestana or 'Scarlet Four Seasons' Rose' (now known simply as 'The Portland Rose'). The whole class of Portland roses was thence developed from that one rose. The first repeat-flowering class of rose with fancy European-style blossoms, they are mostly descended from hybrids between damask and China roses. The plants tend to be fairly short and shrubby, with proportionately short flower stalks. Example: 'James Veitch', 'Rose de Rescht', 'Comte de Chambourd'.
BourbonBourbons originated on l'Île de Bourbon (now called Réunion) off the coast of Madagascar in the Indian Ocean. They are most likely the result of a cross between the Autumn Damask and the 'Old Blush' China rose, both of which were frequently used as hedging materials on the island. They flower repeatedly over vigorous, frequently semi-climbing shrubs with glossy foliage and purple-tinted canes. They were first Introduced in France in 1823. Examples: 'Louise Odier', 'Mme. Pierre Oger', 'Zéphirine Drouhin'.
NoisetteThe first Noisette rose was raised as a hybrid seedling by a South Carolina rice planter named John Champneys. Its parents were the China Rose 'Parson's Pink' and the autumn-flowering musk rose (Rosa moschata), resulting in a vigorous climbing rose producing huge clusters of small pink flowers from spring to fall. Champneys sent seedlings of his rose (called 'Champneys' Pink Cluster') to his gardening friend, Philippe Noisette, who in turn sent plants to his brother Louis in Paris, who then introduced 'Blush Noisette' in 1817. The first Noisettes were small-blossomed, fairly winter-hardy climbers, but later infusions of Tea rose genes created a Tea-Noisette subclass with larger flowers, smaller clusters, and considerably reduced winter hardiness. Examples: 'Blush Noisette', 'Mme. Alfred Carriere' (Noisette), 'Marechal Niel' (Tea-Noisette). (See French and German articles on Noisette roses)
TeaThe result of crossing two of the original China roses ('Hume's Blush China' and 'Parks' Yellow Tea Scented China') with various Bourbons and Noisette roses, tea roses are considerably more tender than other Old Garden Roses (due to cold-tender Rosa gigantea in the ancestry of the 'Parks' Yellow' rose). The teas are repeat-flowering roses, named for their fragrance being reminiscent of Chinese black tea (although this is not always the case). The color range includes pastel shades of white, pink and yellow, and the petals tend to roll back at the edges, producing a petal with a pointed tip. The individual flowers of many cultivars are semi-pendent and nodding, due to weak flower stalks. Examples: 'Lady Hillingdon', 'Maman Cochet'.
Hybrid PerpetualThe dominant class of roses in Victorian England, they first emerged in 1838 and were derived to a great extent from the Bourbons. They became the most popular garden and florist roses of northern Europe at the time, as the tender tea roses would not thrive in cold climates. The "perpetual" in the name hints at repeat-flowering, but many varieties of this class had poor reflowering habits; the tendency was for a massive spring bloom, followed by either scattered summer flowering, a smaller autumn burst, or sometimes nothing at all until next spring. Due to a limited color palette (white, pink, red) and lack of reliable repeat-bloom, the hybrid perpetuals were ultimately overshadowed by their own descendants, the Hybrid Teas. Examples: 'Ferdinand Pichard', 'Reine Des Violettes', 'Paul Neyron'.
Hybrid Musk - This group was primarily developed by Rev. Joseph Pemberton, a British rosarian, in the first decades of the 20th century, based upon 'Aglaia', a 1896 cross by Peter Lambert. A seedling of this rose, 'Trier', is considered to the be foundation of the class. The genetics of the class are somewhat obscure, as some of the parents are unknown. Rose multiflora, however, is known to be one parent, and R. moschata (the musk rose) also figures in its heritage, though it is considered to be less important than the name would suggest. Hybrid musks are disease-resistant, remontant and generally cluster-flowered, with a strong, characteristic "musk" scent.[3][4] Examples include 'Buff Beauty' and 'Penelope'.
Bermuda "Mystery" Roses — A group of several dozen "found" roses that have been grown in
Bermuda for at least a century. The roses have significant value and interest for those growing roses in tropical and semi-tropical regions, since they are highly resistant to both nematode damage and the fungal diseases that plague rose culture in hot, humid areas, and capable of blooming in hot and humid weather. Most of these roses are likely Old Garden Rose cultivars that have otherwise dropped out of cultivation, or sports thereof. They are "mystery roses" because their "proper" historical names have been lost. Tradition dictates that they are named after the owner of the garden where they were rediscovered.
MiscellaneousThere are also a few smaller classes (such as Scots, Sweet Brier) and some climbing classes of old roses (including Ayrshire, Climbing China, Laevigata, Sempervirens, Boursault, Climbing Tea, and Climbing Bourbon). Those classes with both climbing and shrub forms are often grouped together.
Modern Garden RosesClassification of modern roses can be quite confusing because many modern roses have old garden roses in their ancestry and their form varies so much. The classifications tend to be by growth and flowering characteristics, such as "large-flowered shrub", "recurrent, large-flowered shrub", "cluster-flowered", "rambler recurrent", or "ground-cover non-recurrent". The following includes the most notable and popular classifications of Modern Garden Roses:
Hybrid TeaThe favourite rose for much of the history of modern roses, hybrid teas were initially created by hybridizing Hybrid Perpetuals with Tea roses in the late 1800s. 'La France,' created in 1867, is universally acknowledged as the first indication of a new class of roses. Hybrid teas exhibit traits midway between both parents: hardier than the teas but less hardy than the hybrid perpetuals, and more everblooming than the hybrid perpetuals but less so than the teas. The flowers are well-formed with large, high-centered buds, and each flowering stem typically terminates in a single shapely bloom. The shrubs tend to be stiffly upright and sparsely foliaged, which today is often seen as a liability in the landscape. The hybrid tea class is important in being the first class of roses to include genes from the old Austrian brier rose (Rosa foetida). This resulted in an entirely new color range for roses: shades of deep yellow, apricot, copper, orange, true scarlet, yellow bicolors, lavender, gray, and even brown were now possible. The new color range did much to skyrocket hybrid tea popularity in the 20th century, but these colors came at a price: Rosa foetida also passed on a tendency toward disease-susceptibility, scentless blooms, and an intolerance of pruning, to its descendants. Hybrid teas became the single most popular class of garden rose of the 20th century; today, their reputation as being more high maintenance than many other rose classes has led to a decline in hybrid tea popularity among gardeners and landscapers in favor of lower-maintenance "landscape" roses. The hybrid tea remains the standard rose of the floral industry, however, and is still favoured in small gardens in formal situations. Examples: 'Peace', 'Mr. Lincoln,' 'Double Delight.'
PolyanthaLiterally "many-flowered" roses, from the Greek "poly" (many) and "anthos" (flower). Originally derived from crosses between two East Asian species (Rosa chinensis and R. multiflora), polyanthas first appeared in France in the late 1800s alongside the hybrid teas. They featured short plants — some compact, others spreading in habit — with tiny blooms (1" in diameter on average) carried in large sprays, in the typical rose colors of white, pink and red. Their main claim to fame was their prolific bloom: From spring to fall, a healthy polyantha shrub might be literally covered in flowers, creating a strong color impact in the landscape. Polyantha roses are still regarded as low-maintenance, disease-resistant garden roses today, and remain popular for that reason. Examples: 'Cecile Brunner', 'The Fairy', 'Red Fairy'.
FloribundaRose breeders quickly saw the value in crossing polyanthas with hybrid teas, to create roses with that bloomed with the polyantha profusion, but with hybrid tea floral beauty and color range. In 1909, the first polyantha/hybrid tea cross, 'Gruss an Aachen,' was created, with characteristics midway between both parent classes. As the larger, more shapely flowers and hybrid-tea-like growth habit separated these new roses from polyanthas and hybrid teas alike, a new class was created and named Floribunda, Latin for "many-flowering." Typical floribundas feature stiff shrubs, smaller and bushier than the average hybrid tea but less dense and sprawling than the average polyantha. The flowers are often smaller than hybrid teas but are carried in large sprays, giving a better floral effect in the garden. Floribundas are found in all hybrid tea colors and with the classic hybrid tea-shaped blossom, sometimes differing from hybrid teas only in their cluster-flowering habit. Today they are still used in large bedding schemes in public parks and similar spaces. Examples: 'Dainty Maid', 'Iceberg', 'Tuscan Sun'.
GrandifloraGrandifloras (Latin for "large-flowered") were the class of roses created in the mid 1900s to designate back-crosses between hybrid teas and floribundas that fit neither category — specifically, the 'Queen Elizabeth' rose, which was introduced in 1954[5]. Grandiflora shrubs are typically larger than either hybrid teas or floribundas, and feature hybrid tea-style flowers borne in small clusters of three to five, similar to a floribunda. Grandifloras maintained some popularity from about the 1950s to the 1980s but today they are much less popular than either the hybrid teas or the floribundas. Examples: 'Queen Elizabeth', 'Comanche,' 'Montezuma'.

Meillandine (a miniature rose) in a terra cotta flowerpot
MiniatureAll of the classes of Old Garden Roses — gallicas, centifolias, etc. — had corresponding miniature forms, although these were once-flowering just as their larger forms were. As with the standard-sized varieties, miniature Old Garden roses were crossed with repeat-blooming Asian species to produce everblooming miniature roses. Today, miniature roses are represented by twiggy, repeat-flowering shrubs ranging from 6" to 36" in height, with most falling in the 12"–24" height range. Blooms come in all the hybrid tea colors; many varieties also emulate the classic high-centered hybrid tea flower shape. Miniature roses are often marketed and sold by the floral industry as houseplants, but it is important to remember that these plants are largely descended from outdoor shrubs native to temperate regions; thus, most miniature rose varieties require an annual period of cold dormancy to survive. Examples: 'Petite de Hollande' (Miniature Centifolia, once-blooming), 'Cupcake' (Modern Miniature, repeat-blooming).
Climbing/RamblingAs is the case with Miniature roses, all aforementioned classes of roses, both Old and Modern, have "climbing" forms, whereby the canes of the shrubs grow much longer and more flexible than the normal ("bush") forms. In the Old Garden Roses, this is often simply the natural growth habit of many cultivars and varieties; in many Modern roses, however, climbing roses are the results of spontaneous mutations. For example, 'Climbing Peace' is designated as a "Climbing Hybrid Tea," for it is genetically identical to the normal "shrub" form of the 'Peace' hybrid tea rose, except that its canes are long and flexible, i.e. "climbing." Most Climbing roses grow anywhere from 8'–20' in height and exhibit repeat-bloom. Rambler roses, although technically a separate class, are often lumped together with climbing roses. They also exhibit long, flexible canes, but are distinguished from true climbers in two ways: A larger overall size (20'–30' tall is common), and a once-blooming habit. It should be noted that both climbing roses and rambling roses are not true vines such as ivy, clematis or wisteria; they lack the ability to cling to supports on their own, and must be manually trained and tied over structures such as arbors and pergolas. Examples: 'Blaze' (repeat-blooming climber), 'American Pillar' (once-blooming rambler).
English/David Austin Although not officially recognized as a separate class of roses by any established rose authority, English (aka David Austin) roses are often set aside as such by consumers and retailers alike. They were conceptualized and created in the 1960s by David Austin of Shropshire, England, who wanted to rekindle interest in Old Garden Roses by hybridizing OGRs with modern hybrid teas and floribundas. The idea was to create a new group of roses that featured blooms with old-fashioned shapes and fragrances, evocative of classic gallica, alba and damask roses, but with modern repeat-blooming characteristics and the larger modern color range as well. Austin mostly succeeded in his mission; his tribe of "English" roses, now numbering hundreds of varieties, has been warmly embraced by the gardening public and are widely available to consumers. It should be noted that the typical winterhardiness and disease-resistance of the classic Old Garden Roses has largely been compromised in the process; many English roses are susceptible to the same disease problems that plague modern hybrid teas and floribundas, and many are not hardy north of USDA Zone 5. Examples: 'Mary Rose,' 'Graham Thomas', 'Tamora'.
Landscape RosesThese are a modern classifation of rose developed mainly for mass amenity planting. In the late 20th century, traditional hybrid tea and floribunda rose varieties fell out of favor amid gardeners and landscapers, as they are often labor- and chemical-intensive plants susceptible to myriad pest and disease problems. So-called "landscape" roses have thus been developed to fill the consumer desire for a garden rose that offers color, form and fragrance, but is also low maintenance and easy to care for. Most landscape roses having the following characteristics:
Good disease resistance
Lower growing habit, usually under 60cm
Repeat flowering
Disease and pest resistance
Non suckering, growing on their own roots.
Principal parties involved in the breeding of new Landscape Roses varieties are Werner Noak (Germany) Meidiland Roses (France) Boot&Co. (Netherlands)

Pruning
Rose pruning, sometimes regarded as a horticultural art form, is largely dependent on the type of rose to be pruned, the reason for pruning, and the time of year it is at the time of the desired pruning.
Most Old Garden Roses of strict European heritage (albas, damasks, gallicas, etc.) are shrubs that bloom once yearly, in late spring or early summer, on two-year-old (or older) canes. As such, their pruning requirements are quite minimal, and are overall similar to any ot
her analogous shrub, such as lilac or forsythia. Generally, only old, spindly canes should be pruned away, to make room for new canes. One-year-old canes should never be pruned because doing so will remove next year's flower buds. The shrubs can also be pruned back lightly, immediately after the blooms fade, to reduce the overall height or width of the plant. In general, pruning requirements for OGRs are much less laborious and regimented than for Modern hybrids.
Modern hybrids, including the hybrid teas, floribundas, grandifloras, modern miniatures, and English roses, have a complex genetic background that almost always includes China roses (R. chinensis). China roses were evergrowing, everblooming roses from humid subtropical regions that bloomed constantly on any new vegetative growth produced during the growing season. Their modern hybrid descendants exhibit similar habits: Unlike Old Garden Roses, modern hybrids bloom continuously (until stopped by frost) on any new canes produced during the growing season. They therefore require pruning away of any spent flowering stem, in order to divert the plant's energy into producing new growth and thence new flowers.
Additionally, Modern Hybrids planted in cold-winter climates will almost universally require a "hard" annual pruning (reducing all canes to 8"–12" in height) in early spring. Again, because of their complex China rose background, Modern Hybrids are typically not as cold-hardy as European OGRs, and low winter temperatures often desiccate or kill exposed canes. In spring, if left unpruned, these damanged canes will often die back all the way to the shrub's root zone, resulting in a weakened, disfigured plant. The annual "hard" pruning of hybrid teas, floribundas, etc. should generally be done in early spring; most gardeners coincide this pruning with the blooming of forsythia shrubs. Canes should be cut about 1/2" above a vegetative bud (identifiable as a point on a cane where a leaf once grew).
For both Old Garden Roses and Modern Hybrids, any weak, damaged or diseased growth should be pruned away completely, regardless of the time of year. Any pruning of any rose should also be done so that the cut is made at a forty five degree angle above a vegetative bud. This helps the pruned stem callus over more quickly, and also mitigates moisture buildup over the cut, which can lead to disease problems.
For all general rose pruning (including cutting flowers for arrangements), sharp secateurs (hand-held, sickle-bladed pruners) should be used to cut any growth 1/2" or less in diameter. For canes of a thickness greater than 1/2", pole loppers or a small handsaw are generally more effective; secateurs may be damaged or broken in such instances.

Deadheading
Deadheading is the simple practice of manually removing any spent, faded, withered or discoloured flowers from rose shrubs over the course of the blooming season. In Modern Hybrid roses, this is done for several reasons: To promote rebloom, to keep shrubs looking tidy, to eliminate stem dieback (see Pruning, above) and to eliminate excess debris accumulation in the garden.
Deadheading is not as necessary with Old Garden Roses, as it will not promote rebloom in any once-blooming varieties, but can still be done after the flowers fade for aesthetic purposes.

History
The rose has always been valued for its beauty and has a long history of symbolism. The ancient Greeks and Romans identified the rose with their goddesses of love referred to as Aphrodite and Venus. In Rome a wild rose would be placed on the door of a room where secret or confidential matters were discussed. The phrase sub rosa, or "under the rose", means to keep a secret — derived from this ancient Roman practice.
Early Christians identified the five petals of the rose with the five wounds of Christ. Despite this interpretation, their leaders were hesitant to adopt it because of its association with Roman excesses and pagan ritual. The red rose was eventually adopted as a symbol of the blood of the Christian martyrs. Roses also later came to be associated with the Virgin Mary.
Rose culture came into its own in Europe in the 1800s with the introduction of perpetual blooming roses from China. There are currently thousands of varieties of roses developed for bloom shape, size, fragrance and even for lack of prickles.

Culture

A Red rose
Roses are ancient symbols of love and beauty. The rose was sacred to a number of goddesses (including Isis and Aphrodite), and is often used as a symbol of the Virgin Mary. Roses are so important that the word means pink or red in a variety of languages (such as Romance languages, Greek, and Polish).
The rose is the national flower of England and the United States[6], as well as being the symbol of England Rugby, and of the Rugby Football Union. It is also the provincial flower of Yorkshire and Lancashire in England (the white rose and red rose respectively) and of Alberta (the wild rose), and the state flower of four US states: Iowa and North Dakota (R. arkansana), Georgia (R. laevigata), and New York[7] (Rosa generally). Portland, Oregon counts "City of Roses" among its nicknames, and holds an annual Rose Festival.
Roses are occasionally the basis of design for rose windows, such windows comprising five or ten segments (the five petals and five sepals of a rose) or multiples thereof; however most Gothic rose windows are much more elaborate and were probably based originally on the wheel and other symbolism.
A red rose (often held in a hand) is also a symbol of socialism or social democracy; it is also used as a symbol by the British and Irish Labour Parties, as well as by the French, Spanish (Spanish Socialist Workers' Party), Portuguese, Norwegian, Danish, Swedish, Finnish, Brazilian, Dutch (Partij van de Arbeid) and European socialist parties. This originates from the red rose used as a badge by the marchers in the May 1968 street protests in Paris. White Rose was a World War II non violent resistance group in Germany.

Symbolism
Further information: Rose (symbolism)
According to the "language of flowers", certain rose colors carry specific symbolic meanings.

Rosa canina (Dog Rose) flower

Red rose: Deepest love and respect.

Pink rose: Grace.

White rose: Innocence.
Red: love, used to say "I love you," but also stands for courage and respect.
Red & White Together or White Roses with Red Edges signify unity and togetherness.
Pink: symbolizes grace, sophistication and elegance. Also symbolizes gentle feelings of love and friendship.
Dark Pink: Gratefulness and appreciation.
Light Pink: Admiration, sympathy
White: Innocence, purity, secrecy, friendship, reverence and humility.
Yellow: Often akin to joy and deep friendship or platonic love. In German speaking countries, however, they can mean jealousy and infidelity.
Yellow with red tips: Symbolizes a gesture of falling in love.
Orange or Coral symbolizes enthusiasm and desire
Burgundy: Beauty
Blue: Mystery
Further information: blue rose
Green: Calm
Black: used to signify death (black being the color of death) often of old habits. In a positive light it signifies rebirth after death. Also, slavish devotion (as a true black rose is impossible to produce).
Purple: protection (paternal/maternal love)
The rose also has various supernatural and literary attributes.
Pale Colors:convey warmth and friendship.
A Dozen Roses: stand for "there are dozens of ways I care about you."
Two Dozen Roses: stands for the 24 hours in a day and tells that "you think about them every hour".
Three Dozen Roses: signify a romantic attachment unlike any other.
Four Dozen Roses: mean unchanging and unconditional love.

วันเสาร์ที่ 16 กุมภาพันธ์ พ.ศ. 2551

Naming and etymology
The lion's name, similar in many Romance languages, derives from the Latin leo,[3] and before that the Ancient Greek leōn/λεων.[4] The Hebrew word lavi (לָבִיא) may also be related,[5] as well as the Ancient Egyptian rw.[6] It was one of the many species originally described, as Felis leo, by Linnaeus in his eighteenth century work, Systema Naturae.[7] The generic component of its scientific designation, Panthera leo, is often presumed to derive from Greek pan- ("all") and ther ("beast"), but this may be a folk etymology. Although it came into English through the classical languages, panthera is probably of East Asian origin, meaning "the yellowish animal," or "whitish-yellow".[8]

Taxonomy and evolution

Skull of a modern lion at Kruger National Park
The oldest lion-like
fossil is known from Laetoli in Tanzania and is perhaps 3.5 million years old; some scientists have identified the material as Panthera leo. These records are not well-substantiated, and all that can be said is that they pertain to a Panthera-like felid. The oldest confirmed records of Panthera leo in Africa are about 2 million years younger.[9] The closest relatives of the lion are the other Panthera species: the tiger, the jaguar and the leopard. Morphological and genetic studies reveal that the tiger was the first of these recent species to diverge. About 1.9 million years ago the Jaguar branched off the remaining group, which contained ancestors of the leopard and lion. The Lion and leopard subsequently separated about 1 to 1.25 million years ago from each other.[10]
Panthera leo itself evolved in Africa between 1 million and 800,000 years ago before spreading throughout the Holarctic region;[11] It appeared in Europe for the first time 700,000 years ago with the subspecies Panthera leo fossilis at Isernia in Italy. From this lion derived the later Cave lion (Panthera leo spelaea), which appeared about 300,000 years ago. During the upper Pleistocene the lion spread to North and South America, and developed into Panthera leo atrox, the American lion.[12] Lions died out in northern Eurasia and America at the end of the last glaciation, about 10,000 years ago;[13] this may have been secondary to the extinction of megafauna.[14]

Southwest African lion (Panthera leo bleyenberghi)
Traditionally 12 recent subspecies of lion were recognized, the largest of which has been recognised as the
Barbary lion.[15] The major differences between these subspecies are location, mane appearance, size and distribution. Because these characteristics are very insignificant and show a high individual variability, most of these forms were debatable and probably invalid; additionally, they were often based upon zoo material of unknown origin that may have had "striking, but abnormal" morphological characteristics.[16] Today only eight subspecies are usually accepted,[17][13] but one of these, the Cape lion formerly described as Panthera leo melanochaita is probably invalid.[17] Even the remaining seven subspecies might be too much; mitochondrial variation in recent African lions is modest, which suggests that all sub-Saharan lions could be considered a single subspecies, possibly divided in two main clades: one to the west of the Great Rift Valley and the other to the east. Lions from Tsavo in Eastern Kenya are much closer genetically to lions in Transvaal (South Africa), than to those in the Aberdare Range in Western Kenya.[18][19]

Recent
Eight recent subspecies are recognized today:
P. l. persica, known as the
Asiatic- or South Asian, Persian or Indian lion, was once widespread from Turkey, across the Middle East, to Pakistan, India and even Bangladesh. However, large prides and daylight activity made it easier to poach than tigers or leopards; now around 300 exist in and near the Gir Forest of India.[20]
P. l. leo, known as the
Barbary lion, is extinct in the wild due to excessive hunting, although captive individuals may still exist. This was the largest of the lion subspecies, at 3–3.5m approx., and weighing over 150 kilograms and more. They ranged from Morocco to Egypt. The last wild Barbary lion was killed in Morocco in 1922.[21]
P. l. senegalensis, known as the West African lion, is found in Western Africa, from Senegal to Nigeria.
P. l. azandica, known as the North East Congo lion, is found in the Northeastern parts of the
Congo.
P. l. nubica, known as the East African- or Massai lion, is found in East Africa, from
Ethiopia and Kenya to Tanzania and Mozambique.
P. l. bleyenberghi, known as the Southwest African- or Katanga lion. It is found in southwestern Africa,
Zimbabwe, Angola, Katanga (Zaire).
P. l. krugeri, known as the Southeast African- or Transvaal lion, is found in the
Transvaal region of South eastern Africa, including Kruger National Park.
P. l. melanochaita, known as the
Cape lion, became extinct in the wild around 1860. Results of mitochondrial DNA research do not support the status as a distinct subspecies. It seems probable that the Cape lion was only the southernmost population of the extant southern African lion.[17]

Prehistoric
Several additional subspecies of lion existed in prehistoric times:
P. l. atrox, known as the
American lion or American cave lion, was abundant in the Americas from Alaska to Peru in the Pleistocene Epoch until about 10,000 years ago. This form as well as the cave lion are sometimes considered to represent separate species, but recent phylogenetic studies lead to suggest, that they are in fact subspecies of the lion (Panthera leo).[13] One of the largest lion subspecies to have existed, its body length is estimated to have been 1.6–2.5 m (5–8 ft).[22]
P. l. fossilis, known as the
Early Middle Pleistocene European cave lion, flourished about 500,000 years ago; fossils have been recovered from Germany and Italy.

Cave lions, Chamber of Felines, Lascaux caves
P. l. spelaea, known as the
European cave lion, Eurasian cave lion or Upper Pleistocene European cave lion, occurred in Eurasia 300,000 to 10,000 years ago.[13] This species is known from Paleolithic cave paintings (such as the one displayed to the right), ivory carvings, and clay busts, [23] indicating it had protruding ears, tufted tails, perhaps faint tiger-like stripes, and that at least some males had a ruff or primitive mane around their necks.[24] With this example being a hunting scene it is likely that it depicts females hunting for the pride using the same strategy as their contemporary relatives and males may not be part of the subject.
P. l. vereshchagini, known as the East Siberian- or
Beringian cave lion, was found in Yakutia (Russia), Alaska (USA), and the Yukon Territory (Canada). Analysis of skulls and mandibles of this lion demonstrate that it is distinct—larger than the European cave lion and smaller than the American cave lion with differing skull proportions.[25][13]

Dubious
P. l. sinhaleyus, known as the Sri Lanka lion, appears to have become extinct around 39,000 years ago. It is only known from two teeth found in deposits at Kuruwita. Based on these teeth, P. Deraniyagala erected this subspecies in 1939.[26]
P. l. europaea, known as the
European lion, was probably identical with Panthera leo persica or Panthera leo spelea; its status as subspecies is unconfirmed. It became extinct around 100 AD due to persecution and over-exploitation. Inhabited the Balkans, the Italian Peninsula, southern France and the Iberian Peninsula. It was a very popular object of hunting among Romans, Greeks and Macedonians.
P. l. youngi or Panthera youngi , known as the
North-Eastern Pleistocene China cave lion, flourished 350,000 years ago.[27] Its relationship to the extant lion subspecies is obscure, and probably represents a distinct species.
P. l. maculatus, known as the
Marozi or Spotted lion, is sometimes believed to be a distinct subspecies, but may be an adult lion that has retained its juvenile spotted pattern. If it was a subspecies in its own right, rather than a small number of aberrantly colored individuals, it has been extinct since 1931. A less likely identity is a natural leopard/lion hybrid commonly known as a leopon.[28]

Hybrids

A liger is the offspring of a male lion and female tiger.
Further information:
Panthera hybrid, liger and tigon
Lions also have been known to
breed with tigers (most often the Amur and Bengal subspecies) to create hybrids called ligers and tigons.[29] They have also been crossed with leopards to produce leopons,[30] and jaguars to produce jaglions. The marozi is reputedly a spotted lion or a naturally occurring leopon, while the Congolese spotted lion is a complex lion/jaguar/leopard hybrid called a lijagulep. Such hybrids were once commonly bred in zoos, but this is now discouraged due to the emphasis on conserving species and subspecies. Hybrids are still bred in private menageries and in zoos in China.
The liger is a cross between a male lion and a tigress.
[31] Because the lion sire passes on a growth-promoting gene, but the corresponding growth-inhibiting gene from the female lion is absent, ligers grow far larger than either parent. They share physical and behavioural qualities of both parent species (spots and stripes on a sandy background). Male ligers are sterile, but female ligers are often fertile. Males have about a 50% chance of having a mane, but if they grow one their manes will be modest: around 50% of a pure lion mane. Ligers are typically between 3.0 and 3.7 m (10 to 12 feet) in length, and can be between 360 and 450 kg (800 to 1,000 pounds) or more.[31] The less common tigon is a cross between the lioness and the male tiger.[32]

Physical characteristics

During confrontations with others, the mane makes the lion look bigger than he really is.
The lion is the second largest feline after the
tiger. With powerful legs, a strong jaw, and long canine teeth, the lion can bring down and kill large prey.[33] Lion coloration varies from light buff to yellowish, reddish or dark ochraceous brown. The underparts are generally lighter and the tail tuft is black. The color of the mane varies from blond to black.
Weights for adult lions generally lie between 150–250 kg (330–550 lb) for males, and 120–180 kg (260–400 lb) for females.
[2] Nowell and Jackson report average weights of 181 kg for males and 126 kg for females; one male shot near Mount Kenya was weighed at 272 kg (600 lb).[21] Head and body length is 170–250 cm (5 ft 7 in–8 ft 2 in) in males and 140–175 cm (4 ft 7 in–5 ft 9 in) in females; shoulder height is about 123 cm (4 ft) in males and 100 cm (3 ft 3 in) in females. The tail length is 70–100 cm (2 ft 3 in–3 ft 3 in).[2] The tail ends in a hairy tuft. The tuft conceals a spine, approximately 5 mm long, formed of the final sections of tail bone fused together. The lion is the only felid to have a tufted tail and the function of the tuft and spine are unknown. Absent at birth, the tuft develops around 5½ months of age and readily identifiable at 7 months.[34]

Mane

Thermal image of a lion, showing the insulating manes
The mane of the male lion, unique amongst cats, is one of the most distinctive characteristics of the species. It makes the lion appear larger, providing an excellent intimidation display; this aids the lion during confrontations with other lions and with the species' chief competitor in Africa, the
spotted hyena.[35] The presence, absence, color, and size of the mane is associated with genetic precondition, sexual maturity, climate and testosterone production; the rule of thumb is the darker and fuller the mane, the healthier the lion.[36] Research in Tanzania also suggests mane length signals fighting success in male-male relationships. Darker-maned individuals may have longer reproductive lives and higher offspring survival, although they suffer in the hottest months of the year.[37] In prides including a coalition of two or three males, it is possible that lionesses solicit mating more actively with heavily maned lions.[36]
Scientists once believed that the distinct status of some subspecies could be justified by morphology, including the size of the mane. Morphology was used to identify subspecies such as the Barbary lion and Cape lion. Research has suggested, however, that environmental factors influence the color and size of a lion's mane, such as the ambient temperature.[37] The cooler ambient temperature in European and North American zoos, for example, can result in a heavy mane. Thus the mane is an inappropriate marker for identifying subspecies.[17][38] However the males of the Asiatic subspecies are characterized by sparser manes than average African lions.[39]

A maneless male lion, who also has little body hair - from Tsavo East National Park, Kenya
Maneless lions have been reported in
Senegal and Tsavo East National Park in Kenya, and the original male white lion from Timbavati was also maneless. Castrated lions have minimal manes. The lack of a mane is found in inbred lion populations; inbreeding also results in poor fertility.[40]
Cave paintings of extinct European cave lions exclusively show animals with no mane or, just the hint of a mane, suggesting to some that they were more or less maneless,[24] however, the females hunting for a pride are more likely the subjects of the drawings—since they are shown in a group related to hunting—so these images are not reliable to make a judgment about whether the males had manes. The drawings do suggest that the extinct species used the same social orginazation and hunting strategies as contemporary prides.

White lions

White lions owe their coloring to a recessive gene; they are rare forms of the subspecies Panthera leo krugeri
The
white lion is not a distinct subspecies, but a special morph with a genetic condition, leucism,[16] that causes paler colouration akin to that of the white tiger; the condition is similar to melanism, which causes black panthers. White animals of the Transvaal lion (Panthera leo krugeri) have been occasionally encountered in and around the Kruger National Park and the adjacent Timbavati Private Game Reserve in eastern South Africa, but are more commonly found in captivity, where breeders deliberately select them. The unusual cream color of their coats is due to a recessive gene.[41] They have been reportedly bred in camps in South Africa for use as trophies for canned hunts.[42]
Confirmation of the actual existence of the White lion only came in the late twentieth century. For hundreds of years prior, the White lion had been a figment of legend circulating through South Africa, the white pelage of the animal said to represent the goodness in all creatures. Claimed sightings were first reported in the early 1900s, and continued, infrequently, for almost 50 years until, in 1975, a litter of white lion cubs were found at Timbavati Game Reserve.[43]

Biology and behavior
Lions spend much of their time resting and are inactive for about 20 hours per day.[44] Although lions can be active at any time, their activity generally peaks after dusk with a period of socializing, grooming and defecating. Intermittent bursts of activity follow through the night hours to dawn, when hunting most often takes place. They spend an average two hours a day walking and 50 minutes eating.[45]

Hunting and diet

While a lioness such as this, has very sharp teeth, prey is usually killed by strangulation
Lionesses are powerful animals who usually hunt in groups and stalk their chosen prey. They can reach speeds of 59 km/h (40 mph),
[46] although, only for short bursts,[47] so they have to be close to their prey before starting the attack. They take advantage of factors that reduce visibility; many kills take place near some form of cover or at night.[48] They sneak up to the victim until they reach a distance of approximately 30 m (98 feet) or less. Typically, several female lions work together and encircle the herd from different points. Once they have closed with a herd, they usually target the closest prey. The attack is short and powerful, they attempt to catch the victim with a fast rush and final leap. The prey usually is killed by strangulation.[49]
The prey consists mainly of large mammals, with a preference for wildebeest, impalas, zebras, buffalo, and warthogs in Africa and nilgai; wild boar and several deer species in India. Many other species are hunted, based on availability. Mainly this will include ungulates weighing between 50 and 300 kg such as kudu, hartebeest, gemsbok, and eland.[2] Occasionally, they take relatively small species such as Thomson's gazelle or springbok. While hunting in groups, they are capable of taking down most animals, even healthy adults, but they rarely attack very large prey such as buffalo bulls or fully grown male giraffes, due to the danger of injury.[50]

Lioness closing in on a zebra, a typical prey
They normally feed on mammals no larger than 550 kg, which excludes most adult
hippopotamuses, rhinoceroses, elephants, giraffes, and buffalos.[51] In some areas, they specialise in hunting atypical prey-species; this is the case at the Savuti river, where they prey on young elephants.[52] Park guides in the area reported that the lions, driven by extreme hunger, started taking down baby elephants, and then moved on to adolescents and, occasionally, fully grown adults.[53] In the Kruger National Park, giraffes are regularly hunted.[54] Lions also attack domestic livestock; in India cattle contribute significantly to their diet.[39] They are capable of killing other predators such as leopards, cheetahs, hyenas, and wild dogs, as well as scavenging animals either dead from natural causes or killed by other predators.[55] A lion may gorge itself and eat up to 30 kg (66 lb) in one sitting;[56] if it is unable to consume all the kill it will rest for a few hours before consuming more. On a hot day, the pride may retreat to shade leaving a male or two to stand guard.[57] An adult lioness requires an average of about 5 kg (11 lb) of meat per day, a male about 7 kg (15.4 lb).[58]

Lions hunting down an African buffalo

The hunters of a pride sharing a zebra where the kill occurred
Because lionesses hunt in open spaces where they are easily seen by their prey, cooperative hunting increases the likelihood of a successful hunt; this is especially true with larger species. Teamwork also enables them to defend their prey more easily against other large predators such as hyenas, which may be attracted by
vultures over kilometers in open savannas. Lionesses do most of the hunting. In typical hunts, each lioness has a favored position in the group, either stalking prey on the "wing" then attacking, or moving a smaller distance in the centre of the group and capturing prey in flight from other lionesses.[59]
Males attached to prides do not usually participate, except when hunting large animals such as buffalo and giraffe. Young lions first display stalking behaviour around three months of age, although they do not participate in hunting until they are almost a year old. They begin to hunt effectively when nearing the age of two.[60]