A shrub or bush is a small- to medium-sized woody plant. Unlike herbaceous plants, shrubs have persistent woody, they are distinguished from trees by their multiple stems and shorter height, are under 6 m tall. Plants of many species may grow either depending on their growing conditions. Small, low shrubs less than 2 m tall, such as lavender and most small garden varieties of rose, are termed "subshrubs". An area of cultivated shrubs in a park or a garden is known as a shrubbery; when clipped as topiary, suitable species or varieties of shrubs develop dense foliage and many small leafy branches growing close together. Many shrubs respond well to renewal pruning, in which hard cutting back to a "stool" results in long new stems known as "canes". Other shrubs respond better to selective pruning to reveal their character. Shrubs in common garden practice are considered broad-leaved plants, though some smaller conifers such as mountain pine and common juniper are shrubby in structure. Species that grow into a shrubby habit may be either evergreen.
In botany and ecology, a shrub is more used to describe the particular physical structural or plant life-form of woody plants which are less than 8 metres high and have many stems arising at or near the base. For example, a descriptive system adopted in Australia is based on structural characteristics based on life-form, plus the height and amount of foliage cover of the tallest layer or dominant species. For shrubs 2–8 metres high the following structural forms are categorized: dense foliage cover — closed-shrub mid-dense foliage cover — open-shrub sparse foliage cover — tall shrubland sparse foliage cover — tall open shrublandFor shrubs less than 2 metres high the following structural forms are categorized: dense foliage cover — closed-heath or closed low shrubland— mid-dense foliage cover — open-heath or mid-dense low shrubland— sparse foliage cover — low shrubland sparse foliage cover — low open shrubland Those marked with * can develop into tree form
The rosids are members of a large clade of flowering plants, containing about 70,000 species, more than a quarter of all angiosperms. The clade is divided into 16 to 20 orders, depending upon circumscription and classification; these orders, in turn, together comprise about 140 families. Fossil rosids are known from the Cretaceous period. Molecular clock estimates indicate that the rosids originated in the Aptian or Albian stages of the Cretaceous, between 125 and 99.6 million years ago. The name is based upon the name "Rosidae", understood to be a subclass. In 1967, Armen Takhtajan showed that the correct basis for the name "Rosidae" is a description of a group of plants published in 1830 by Friedrich Gottlieb Bartling; the clade was renamed "Rosidae" and has been variously delimited by different authors. The name "rosids" is informal and not assumed to have any particular taxonomic rank like the names authorized by the ICBN; the rosids are monophyletic based upon evidence found by molecular phylogenetic analysis.
Three different definitions of the rosids were used. Some authors included the orders Vitales in the rosids. Others excluded both of these orders; the circumscription used in this article is that of the APG IV classification, which includes Vitales, but excludes Saxifragales. The rosids and Saxifragales form the superrosids clade; this is one of three groups that compose the Pentapetalae, the others being Dilleniales and the superasterids. The rosids consist of two groups: the eurosids; the eurosids, in turn, are divided into two groups: malvids. The rosids consist of 17 orders. In addition to Vitales, there are 8 orders in malvids; some of the orders have only been recognized. These are Vitales, Crossosomatales and Huerteales; the phylogeny of Rosids shown below is adapted from the Angiosperm Phylogeny Group website. The nitrogen-fixing clade contains a high number of actinorhizal plants. Not all plants in this clade are actinorhizal, however. Media related to Rosids at Wikimedia Commons
Madeira the Autonomous Region of Madeira, is one of the two autonomous regions of Portugal. It is an archipelago situated in southwest of Portugal, its total population was estimated in 2011 at 267,785. The capital of Madeira is Funchal, located on the main island's south coast; the archipelago is just under 400 kilometres north of Canary Islands. Bermuda and Madeira, a few time zones apart, are the only land in the Atlantic on the 32nd parallel north, it includes the islands of Madeira, Porto Santo, the Desertas, administered together with the separate archipelago of the Savage Islands. The region has political and administrative autonomy through the Administrative Political Statue of the Autonomous Region of Madeira provided for in the Portuguese Constitution; the autonomous region is an integral part of the European Union as an outermost region. Madeira was claimed by Portuguese sailors in the service of Prince Henry the Navigator in 1419 and settled after 1420; the archipelago is considered to be the first territorial discovery of the exploratory period of the Age of Discovery.
Today, it is a popular year-round resort, being visited every year by about 1.4 million tourists five times its population. The region is noted for its Madeira wine, gastronomy and cultural value and fauna, landscapes that are classified as a UNESCO World Heritage Site, embroidery artisans; the main harbour in Funchal has long been the leading Portuguese port in cruise liner dockings, receiving more than half a million tourists through its main port in 2017, being an important stopover for commercial and trans-Atlantic passenger cruises between Europe, the Caribbean and North Africa. In addition, the International Business Centre of Madeira known as the Madeira Free Trade Zone, was created formally in the 1980s as a tool of regional economic policy, it consists of a set of incentives tax-related, granted with the objective of attracting foreign direct investment based on international services into Madeira. Plutarch in his Parallel Lives referring to the military commander Quintus Sertorius, relates that after his return to Cádiz, he met sailors who spoke of idyllic Atlantic islands: "The islands are said to be two in number separated by a narrow strait and lie 10,000 furlongs from Africa.
They are called the Isles of the Blest."Archeological evidence suggests that the islands may have been visited by the Vikings sometime between 900 and 1030. During the reign of King Edward III of England, lovers Robert Machim and Anna d'Arfet were said to have fled from England to France in 1346. Driven off course by a violent storm, their ship ran aground along the coast of an island that may have been Madeira; this legend was the basis of the naming of the city of Machico on the island, in memory of the young lovers. Knowledge of some Atlantic islands, such as Madeira, existed before their formal discovery and settlement, as the islands were shown on maps as early as 1339. In 1418, two captains under service to Prince Henry the Navigator, João Gonçalves Zarco and Tristão Vaz Teixeira, were driven off course by a storm to an island they named Porto Santo in gratitude for divine deliverance from a shipwreck; the following year, an organised expedition, under the captaincy of Zarco, Vaz Teixeira, Bartolomeu Perestrello, traveled to the island to claim it on behalf of the Portuguese Crown.
Subsequently, the new settlers observed "a heavy black cloud suspended to the southwest." Their investigation revealed it to be the larger island. The first Portuguese settlers began colonizing the islands around 1420 or 1425. Grain production began to fall and the ensuing crisis forced Henry the Navigator to order other commercial crops to be planted so that the islands could be profitable; these specialised plants, their associated industrial technology, created one of the major revolutions on the islands and fuelled Portuguese industry. Following the introduction of the first water-driven sugar mill on Madeira, sugar production increased to over 6,000 arrobas by 1455, using advisers from Sicily and financed by Genoese capital; the accessibility of Madeira attracted Genoese and Flemish traders, who were keen to bypass Venetian monopolies. "By 1480 Antwerp had some seventy ships engaged in the Madeira sugar trade, with the refining and distribution concentrated in Antwerp. By the 1490s Madeira had overtaken Cyprus as a producer of sugar."
Sugarcane production was the primary engine of the island's economy, increasing the demand for labour. African slaves were used during portions of the island's history to cultivate sugar cane, the proportion of imported slaves reached 10% of the total population of Madeira by the 16th century. Barbary corsairs from North Africa, who enslaved Europeans from ships and coastal communities throughout the Mediterranean region, captured 1,200 people in Porto Santo in 1617. After the 17th century, as Portuguese sugar production was shifted to Brazil, São Tomé and Príncipe and elsewhere, Madeira's most important commodity product became its wine; the British first amicably occupied the island in 1801 whereafter Colonel William Henry Clinton became governor. A detachment of the 85th Regiment of Foot under Lieutenant-colonel James Willoughby Gordon garrisoned the island. After the Peace of Amiens, British troops withdrew in 1802, only to reoccupy Madeira in 1807 until the end of the Peninsular War in 1814.
On 31 December 1916, during the Great War, a Ge
Euphorbia is a large and diverse genus of flowering plants called spurge, in the spurge family. "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae, not just to members of the genus. Some euphorbias are commercially available, such as poinsettias at Christmas; some are cultivated as ornamentals, or collected and valued for the aesthetic appearance of their unique floral structures, such as the crown of thorns plant. Euphorbias from the deserts of Southern Africa and Madagascar have evolved physical characteristics and forms similar to cacti of North and South America, so they are incorrectly referred to as cacti; some are used as ornamentals in landscaping, because of beautiful or striking overall forms, drought and heat tolerance. Euphorbias range from tiny annual plants to long-lived trees; the genus has over or about 2,000 members, making it one of the largest genera of flowering plants. It has one of the largest ranges of chromosome counts, along with Rumex and Senecio.
Euphorbia antiquorum is the type species for the genus Euphorbia. It was first described by Carl Linnaeus in 1753 in Species Plantarum; the plants share the feature of having a poisonous, white, latex-like sap, unusual and unique floral structures. The genus may be described by properties of its members' gene sequences, or by the shape and form of its heads of flowers; when viewed as a whole, the head of flowers looks like a single flower. It has a unique kind of pseudanthium, called a cyathium, where each flower in the head is reduced to its barest essential part needed for sexual reproduction; the individual flowers are either male or female, with the male flowers reduced to only the stamen, the females to the pistil. These flowers have no sepals, petals, or other parts that are typical of flowers in other kinds of plants. Structures supporting the flower head and beneath have evolved to attract pollinators with nectar, with shapes and colors that function the way petals and other flower parts do in other flowers.
It is the only genus of plants that has all three kinds of photosynthesis, CAM, C3, C4. The genus can be found all over the world; the forms range from annual plants lying to well-developed tall trees. In deserts in Madagascar and southern Africa, convergent evolution has led to cactus-like forms where the plants occupy the same ecological niche as cacti do in deserts of North and South America; the genus is found in the tropical and subtropical regions of Africa and the Americas, but in temperate zones worldwide. Succulent species originate from Africa, the Americas, Madagascar. A wide range of insular species can be found. Among laypeople, Euphorbia species are among the plant taxa most confused with cacti the stem succulents. Euphorbias secrete a sticky, milky-white fluid with latex. Individual flowers of euphorbias are tiny and nondescript, without petals and sepals, unlike cacti, which have fantastically showy flowers. Euphorbias from desert habitats with growth forms similar to cacti have thorns, which are different from the spines of cacti.
The common name "spurge" derives from the Middle English/Old French espurge, due to the use of the plant's sap as a purgative. The botanical name Euphorbia derives from Euphorbos, the Greek physician of king Juba II of Numidia, who married the daughter of Anthony and Cleopatra. Juba was a prolific writer including natural history. Euphorbos wrote. In 12 BC, Juba named this plant after his physician Euphorbos, as Augustus Caesar had dedicated a statue to the brother of Euphorbos, Antonius Musa, the personal physician of Augustus. In 1753, botanist and taxonomist Carl Linnaeus assigned the name Euphorbia to the entire genus in the physician's honor; the plants are annual, biennial or perennial herbs, woody shrubs, or trees with a caustic, poisonous milky latex. The roots are thick and fleshy or tuberous. Many species are less succulent, thorny, or unarmed; the main stem and also the side arms of the succulent species are thick and fleshy, 15–91 cm tall. The deciduous leaves may be opposite, alternate, or in whorls.
In succulent species, the leaves are small and short-lived. The stipules are small transformed into spines or glands, or missing. Like all members of the family Euphorbiaceae, spurges have unisexual flowers. In Euphorbia, flowers occur in a head, called the cyathium; each male or female flower in the cyathium head has only its essential sexual part, in males the stamen, in females the pistil. The flowers do not have sepals, petals, or nectar to attract pollinators, although other nonflower parts of the plant have an appearance and nectar glands with similar roles. Euphorbias are the only plants known to have this kind of flower head. Nectar glands and nectar that attract pollinators are held in the involucre, a cuplike part below and supporting the cyathium head; the involucre is above and supported by bract-like modified leaf structures called cyathophylls', or cyathial leaves
A botanical name is a formal scientific name conforming to the International Code of Nomenclature for algae and plants and, if it concerns a plant cultigen, the additional cultivar or Group epithets must conform to the International Code of Nomenclature for Cultivated Plants. The code of nomenclature covers "all organisms traditionally treated as algae, fungi, or plants, whether fossil or non-fossil, including blue-green algae, oomycetes, slime moulds and photosynthetic protists with their taxonomically related non-photosynthetic groups."The purpose of a formal name is to have a single name, accepted and used worldwide for a particular plant or plant group. For example, the botanical name Bellis perennis denotes a plant species, native to most of the countries of Europe and the Middle East, where it has accumulated various names in many languages; the plant was introduced worldwide, bringing it into contact with more languages. English names for this plant species include: daisy, English daisy, lawn daisy.
The cultivar Bellis perennis'Aucubifolia' is a golden-variegated horticultural selection of this species. The botanical name itself is fixed by a type, a particular specimen of an organism to which the scientific name is formally attached. In other words, a type is an example that serves to anchor or centralize the defining features of that particular taxon; the usefulness of botanical names is limited by the fact that taxonomic groups are not fixed in size. For example, the traditional view of the family Malvaceae has been expanded in some modern approaches to include what were considered to be several related families; some botanical names refer to groups that are stable while for other names a careful check is needed to see which circumscription is being used. Depending on rank, botanical names may be in two parts or three parts; the names of cultivated plants are not similar to the botanical names, since they may instead involve "unambiguous common names" of species or genera. Cultivated plant names may have an extra component, bringing a maximum of four parts: in one part Plantae Marchantiophyta Magnoliopsida Liliidae Pinophyta Fagaceae Betula in two parts Acacia subg.
Phyllodineae lchemilla subsect. Heliodrosium Berberis thunbergii a species name, i.e. a combination consisting of a genus name and one epithet Syringa'Charisma' – a cultivar within a genus Hydrangea Lacecap Group – a genus name and Group epithet Lilium Darkest Red Group – a genus name and Group epithet Paphiopedilum Greenteaicecreamandraspberries grex snowdrop'John Gray' – an unambiguous common name for the genus Galanthus and a cultivar epithetin three parts Calystegia sepium subsp. Americana, a combination consisting of a genus name and two epithets Crataegus azarolus var. pontica Bellis perennis'Aucubifolia' – a cultivar Brassica oleracea Gemmifera Group – a species name and Group epithetin four parts Scilla hispanica var. campanulata'Rose Queen' – a cultivar within a botanical variety apart from cultivars, the name of a plant can never have more than three parts. A botanical name in three parts, i.e. an infraspecific name needs a "connecting term" to indicate rank. In the Calystegia example above, this is "subsp.", for subspecies.
In botany there are many ranks below that of species. A name of a "subdivision of a genus" needs a connecting term; the connecting term is not part of the name itself. A taxon may be indicated by a listing in more than three parts: "Saxifraga aizoon var. aizoon subvar. Brevifolia f. multicaulis subf. surculosa Engl. & Irmsch." But this is a classification, not a formal botanical name. The botanical name is Saxifraga aizoon subf. surculosa Engl. & Irmsch.. Generic and infraspecific botanical names are printed in italics; the example set by the ICN is to italicize all botanical names, including those above genus, though the ICN preface states: "The Code sets no binding standard in this respect, as typography is a matter of editorial style and tradition not of nomenclature". Most peer-reviewed scientific botanical publications do not italicize names above the rank of genus, non-botanical scientific publications do not, in keeping with two of the three other kinds of scientific name: zoological and bacterial.
For botanical nomenclature, the ICN prescribes a two-part name or binary name for any taxon below the rank of genus down to, including the rank of species. Taxa below the rank of species get a three part. A binary name consists of the name of an epithet. In the case of a species this is a specific epithet:Bellis perennis is the name of a species, in which perennis is the specific epithet. There is no connecting term involved. In t
Award of Garden Merit
The Award of Garden Merit is a long-established annual award for plants by the British Royal Horticultural Society. It is based on assessment of the plants' performance under UK growing conditions; the Award of Garden Merit is a mark of quality awarded, since 1922, to garden plants by the United Kingdom, Royal Horticultural Society. Awards are made annually after plant trials intended to judge the plants' performance under UK growing conditions. Trials may last for one or more years, depending on the type of plant being tried out, may be performed at Royal Horticulture Society Garden in Wisley and other gardens or after observation of plants in specialist collections. Trial reports are made available on the website. Awards are reviewed annually in case plants have become unavailable horticulturally, or have been superseded by better cultivars; the award should not be confused with the Royal Horticulture Society's Award of Merit, given to plants deemed'of great merit for exhibition' i.e. for show, not garden, plants.
Since 1989, France has had similar awards called the Mérites de Courson, but these are drawn from a limited number of plants submitted by nurserymen to juries at the twice-yearly Journées des Plantes de Courson and awards are based on the opinions of the jury members as to the plants' performance in French gardens, rather than on extensive trials. The Award of Garden Merit was reviewed in 1992, to increase its prestige. Field trial results gained weight in the assessments and existing AGM plants were reviewed in the light of more recent experience; the AGMs were to be reviewed at 10 year intervals from 1992, but this frequency has been increased to annually. The 2012/13 review, with advice from experts such as Royal Horticultural Society's plant committees, specialist societies, Plant Heritage National Collection holders and others, resulted in many changes. Nearly 1,900 plants lost more than 1,400 plants gained awards. Plants may be added to the Royal Horticultural Society'Sunset List' for rescission for several reasons, including unavailability to gardeners, better plants becoming available, affliction by pests or diseases, or insufficient uniformity.
To qualify for an Award of Garden Merit, a plant must be available horticulturally must be of outstanding excellence for garden decoration or use must be of good constitution must not require specialist growing conditions or care must not be susceptible to any pest or disease must not be subject to an unreasonable degree of reversion. The "Award of Garden Merit" symbol represents a cup-shaped trophy with handles, it is cited together with a hardiness rating as follows: H1 Requires a heated glasshouse H1a Warmer than 15C/59F: tropical plants for indoors and heated greenhouses H1b 10C/50F to 15C/59F: subtropical plants for indoors and heated greenhouses H1c 5C/41F to 10C/50F: warm temperate plants that can go outdoors in summer H2 1C/34F to 5C/41F: plants that need a frost-free greenhouse in winter H3 -5C/23F to 1C/34F: hardy outside in some regions or situations, or which - while grown outside in summer - need frost protection in winter H4 -10C/14F to -5C/23F: plants hardy outside in most of the UK in an average winter H5 -15C/5F to -10C/14F: plants hardy outside in most of the UK in severe winters H6 -20C/-4F to -15C/5F: plants hardy outside in the UK and northern Europe H7 Colder than -20C/-4F: plants hardy outside in the severest European climates List of Award of Garden Merit flowering cherries List of Award of Garden Merit magnolias List of Award of Garden Merit roses List of Award of Garden Merit sweet peas RHS Plant Finder 2005–2006, Dorling Kindersley ISBN 1-4053-0736-6 The Royal Horticultural Society's website - Search facility for AGM plants RHS AGM Plant Awards RHS Plant Committees Search for AGM plants The Royal Horticultural Society Complete AGM lists
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents, but can show hybrid vigour, sometimes growing larger or taller than either parent; the concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how related the parent species are. Species are reproductively isolated by strong barriers to hybridisation, which include morphological differences, differing times of fertility, mating behaviors and cues, physiological rejection of sperm cells or the developing embryo; some act before fertilization and others after it. Similar barriers exist in plants, with differences in flowering times, pollen vectors, inhibition of pollen tube growth, somatoplastic sterility, cytoplasmic-genic male sterility and the structure of the chromosomes.
A few animal species and many plant species, are the result of hybrid speciation, including important crop plants such as wheat, where the number of chromosomes has been doubled. Human impact on the environment has resulted in an increase in the interbreeding between regional species, the proliferation of introduced species worldwide has resulted in an increase in hybridisation; this genetic mixing may threaten many species with extinction, while genetic erosion in crop plants may be damaging the gene pools of many species for future breeding. A form of intentional human-mediated hybridisation is the crossing of wild and domesticated species; this is common in modern agriculture. One such flower, Oenothera lamarckiana, was central to early genetics research into mutationism and polyploidy, it is more done in the livestock and pet trades. Human selective breeding of domesticated animals and plants has resulted is the development of distinct breeds. Hybrid humans existed in prehistory. For example and anatomically modern humans are thought to have interbred as as 40,000 years ago.
Mythological hybrids appear in human culture in forms as diverse as the Minotaur, blends of animals and mythical beasts such as centaurs and sphinxes, the Nephilim of the Biblical apocrypha described as the wicked sons of fallen angels and attractive women. The term hybrid is derived from Latin hybrida, used for crosses such as of a tame sow and a wild boar; the term came into popular use in English in the 19th century, though examples of its use have been found from the early 17th century. Conspicuous hybrids are popularly named with portmanteau words, starting in the 1920s with the breeding of tiger–lion hybrids. From the point of view of animal and plant breeders, there are several kinds of hybrid formed from crosses within a species, such as between different breeds. Single cross hybrids result from the cross between two true-breeding organisms which produces an F1 hybrid; the cross between two different homozygous lines produces an F1 hybrid, heterozygous. The F1 generation is phenotypically homogeneous, producing offspring that are all similar to each other.
Double cross hybrids result from the cross between two different F1 hybrids. Three-way cross hybrids result from the cross between an inbred line. Triple cross hybrids result from the crossing of two different three-way cross hybrids. Top cross hybrids result from the crossing of a top quality or pure-bred male and a lower quality female, intended to improve the quality of the offspring, on average. Population hybrids result from the crossing of plants or animals in one population with those of another population; these crosses between different breeds. In horticulture, the term stable hybrid is used to describe an annual plant that, if grown and bred in a small monoculture free of external pollen produces offspring that are "true to type" with respect to phenotype. Hybridisation can occur in the hybrid zones where the geographical ranges of species, subspecies, or distinct genetic lineages overlap. For example, the butterfly Limenitis arthemis has two major subspecies in North America, L. a. arthemis and L. a. astyanax.
The white admiral has a bright, white band on its wings, while the red-spotted purple has cooler blue-green shades. Hybridisation occurs between a narrow area across New England, southern Ontario, the Great Lakes, the "suture region", it is at these regions. Other hybrid zones have formed between described species of animals. From the point of view of genetics, several different kinds of hybrid can be distinguished. A genetic hybrid carries two different alleles of the same gene, where for instance one allele may code for a lighter coat colour than the other. A structural hybrid results from the fusion of gametes that have differing structure in at least one chromosome, as a result of structural abnormalities. A numerical hybrid results from the fusion of gamet