Rhododendron is a genus of 1,024 species of woody plants in the heath family, either evergreen or deciduous, found in Asia, although it is widespread throughout the highlands of the Appalachian Mountains of North America. It is the national flower of Nepal as well as the state flower of West Washington. Most species have brightly coloured flowers. Azaleas make up two subgenera of Rhododendron, they are distinguished from "true" rhododendrons by having only five anthers per flower. Rhododendron is a genus of shrubs and small to large trees, the smallest species growing to 10–100 cm tall, the largest, R. protistum var. giganteum, reported to 30 m tall. The leaves are spirally arranged, they may be either deciduous. In some species, the undersides of the leaves are covered with hairs; some of the best known species are noted for their many clusters of large flowers. There are alpine species with small flowers and small leaves, tropical species such as section Vireya that grow as epiphytes. Species in this genus may be part of the heath complex in oak-heath forests in eastern North America.
They have been divided based on the presence or absence of scales on the abaxial leaf surface. These scales, unique to subgenus Rhododendron, are modified hairs consisting of a polygonal scale attached by a stalk. Rhododendron are characterised by having inflorescences with scarious perulae, a chromosome number of x=13, fruit that has a septicidal capsule, an ovary, superior, stamens that have no appendages, agglutinate pollen. Rhododendron is the largest genus in the family Ericaceae, with as many as 1,024 species, is morphologically diverse; the taxonomy has been complex. Although Rhododendrons had been known since the description of Rhododendron hirsutum by Charles de l'Écluse in the sixteenth century, were known to classical writers, referred to as Chamaerhododendron, the genus was first formally described by Linnaeus in his Species Plantarum in 1753, he listed five species under Rhododendron. At that time he considered the known six species of Azalea that he had described earlier in 1735 in his Systema Naturae as a separate genus.
Linnaeus' six species of Azalea were Azalea indica, A. pontica, A. lutea, A. viscosa, A. lapponica and A. procumbens, which he distinguished from Rhododendron by having five stamens, as opposed to ten. As new species of what are now considered Rhododendron were discovered, if they seemed to differ from the type species they were assigned to separate genera. For instance Rhodora for Rhododendron canadense and Hymenanthes for Rhododendron metternichii, now R. degronianum. Meanwhile, other botanists such as Salisbury and Tate began to question the distinction between Azalea and Rhododendron, in 1836, Azalea was incorporated into Rhododendron and the genus divided into eight sections. Of these Tsutsutsi, Pogonanthum and Rhodora are still used, the other sections being Lepipherum and Chamaecistus; this structure survived till following which the development of molecular phylogeny led to major re-examinations of traditional morphological classifications, although other authors such as Candolle, who described six sections, used different numeration.
Soon, as more species became available in the nineteenth century so did a better understanding of the characteristics necessary for the major divisions. Chief amongst these were Maximovicz's Rhododendreae Asiae Planchon. Maximovicz used flower bud position and its relationship with leaf buds to create eight "Sections". Bentham and Hooker used a similar scheme, but called the divisions "Series", it was not until 1893 that Koehne appreciated the significance of scaling and hence the separation of lepidote and elepidote species. The large number of species that were available by the early twentieth century prompted a new approach when Balfour introduced the concept of grouping species into series; the Species of Rhododendron referred to this series concept as the Balfourian system. That system continued up to modern times in Davidian's four volume The Rhododendron Species; the next major attempt at classification was by Sleumer who from 1934 began incorporating the Balfourian series into the older hierarchical structure of subgenera and sections, according to the International Code of Botanical Nomenclature, culminating in 1949 with his "Ein System der Gattung Rhododendron L.", subsequent refinements.
Most of the Balfourian series are represented by Sleumer as subsections, though some appear as sections or subgenera. Sleumer based his system on the relationship of the flower buds to the leaf buds, flower structure, whether the leaves were lepidote or non-lepidote. While Sleumer's work was accepted, many in the United States and the United Kingdom continued to use the simpler Balfourian system of the Edinburgh group. Sleumer's system underwent many revisions by others, predominantly the Edinburgh group in their continuing Royal Botanic Garden Edinburgh notes. Cullen of the Edinburgh group, placing more
Nuneham Courtenay is a village and civil parish about 5 miles southeast of Oxford, it occupies a pronounced section of left bank of the River Thames. The parish is bounded on other sides by field boundaries; the 2011 Census recorded the parish's population as 200. The parish is on a light escarpment running north-east to south-west, its highest point is a tiny knoll 100 m above mean sea level, about 500 metres SSW of the clustered-cum-linear village. Between these points is Windmill Hill; the minimum elevation is 52m to 53m along the Thames which follows the line of the central eminent land. Most of the nature reserve Bluebell Wood is on the eastern slopes, across Marsh Baldon's straight and touching boundary to the village nucleus; the parish covers about 2 km north to the same south-west of the point shown and just over 1% of South Oxfordshire's 67.85 km². Its population was 0.15% of the district's total of 134,257. The Oxford Green Belt Way passes through the parish; the toponym was Newenham from the 11th century on, until it was changed to "Nuneham" in 1764.
Just southeast of Lower Farm, about 1 1⁄2 miles northwest of the present Nuneham Courtenay village, is the site of a former Romano-British pottery kiln. The kiln was about 1 1⁄2 miles west of the Roman road that linked the Roman towns at Dorchester on Thames and Alchester, it began production about 100 CE, producing a wide range of fine wares in the 2nd century and increased its product range in the 3rd century. It declined, in about the middle of the 4th century it ceased production; the remains of the kiln were discovered in 1991 during excavations to lay a new water main for Thames Water. Some time between the Norman conquest of England in 1066 and the completion of the Domesday Book in 1086 William the Conqueror granted the manor of Newenham to one of his Norman barons, Richard de Courcy, it remained in his family until the death of his great-grandson, William de Courcy in 1176. It passed from William de Courcy's widow Gundreda via her female heirs to Baldwin de Redvers, 7th Earl of Devon.
Baldwin died without an heir, so Newenham again passed to a female "overlord", Isabella de Fortibus, Countess of Devon. She too died without an heir, but in 1310 King Edward II granted Newenham to Hugh de Courtenay, 9th Earl of Devon. Newenham remained in the Courtenay family until the latter part of the 14th century, when Sir Peter de Courtenay, son of Hugh de Courtenay, 10th Earl of Devon sold his inheritance of the estate to Sir Hugh Segrave. Under the terms of the sale Margaret de Bohun, 2nd Countess of Devon retained the use of Newenham Courtenay for life. However, Sir Hugh Segrave died in 1386 and the Countess outlived him, so upon her death in 1391 the manor passed to Segrave's aunt's grandson, Sir John Drayton, Member of Parliament for Oxfordshire and Gloucestershire. Sir John died in 1417 leaving the manor to his widow Isabel, younger daughter of Sir Maurice Russell of Dyrham and Kingston Russell, Dorset. Isabel married, as her 4th husband, Stephen Hatfield. After some legal problems concerning good title to the manor, in 1425 Isabel and Hatfield sold the reversion of the manor, reserving a life interest to themselves, to Thomas Chaucer, son of the poet Geoffrey Chaucer and Speaker of the House of Commons on five occasions between 1407 and 1421.
Upon Isabel's death in 1437, Newenham Courtenay passed to daughter of Thomas Chaucer. Alice was married to 1st Duke of Suffolk; the manor remained in the de la Pole family until 1502, when Edmund de la Pole, 3rd Duke of Suffolk was outlawed and forfeited his lands for plotting a Yorkist rebellion against Henry VII. In 1514 Henry VIII made his brother-in-law Charles Brandon Duke of Suffolk, granted him the forfeited de la Pole estates. In 1528 Brandon conveyed Newenham Courtenay to Cardinal Wolsey, but the following year King Henry VIII deposed Wolsey; the manor was administered by royal stewards until 1544. Pollard lived at Newenham Courtenay until his death in 1557, he left the use of the manor to his widow Mary, with the estate to pass to two of his male relatives upon her death. However Dame Mary remarried in 1561 and lived to be over 100, outliving the heirs that Pollard had appointed, she died in 1606 and the estate passed to a younger John Pollard. John transferred Newenham Courtenay to his son Lewis, but both men were in debt and in 1634 Lewis sold the estate to the wealthy lawyer Hugh Audley.
In 1640 Audley sold Newenham Courtenay to Bishop of Lichfield and Coventry. Wright supported Archbishop Laud, he died in his son Calvert inherited Newenham Courtenay. Calvert wasted his father's fortune, sold Newenham Courtenay in 1653, was imprisoned as a debtor, died in the King's Bench Prison in Southwark in 1666. Calvert Wright's buyer was John Robinson, a City of London businessman who reported that it cost him more to clear the debts of Newenham Courtenay than to buy the estate. Robinson left the estate to his two daughters, who in 1710 sold it to Sir Simon Harcourt of Stanton Harcourt. Sir Simon was created Viscount Harcourt in 1721 and died in 1727, he was succeeded by his grandson Simon Harcourt, 2nd Viscount Harcourt, created 1st Earl Harcourt in 1749. Upon the death of William Harcourt, 3rd Earl Harcourt in 1830 the earldom became extinct, the estate, now called Nuneham Courtenay, passed to the first Earl's nephew Edward Venables-Vernon, Archbishop of York, who changed his name to Venables-Vernon-Harcourt.
Manorial rights were in England abat
Peafowl is a common name for three species of birds in the genera Pavo and Afropavo of the Phasianidae family, the pheasants and their allies. Male peafowl are referred to as peacocks, female peafowl as peahens; the two Asiatic species are the blue or Indian peafowl of the Indian subcontinent, the green peafowl of Southeast Asia. Male peafowl are known for their extravagant plumage; the latter is prominent in the Asiatic species, which have an eye-spotted "tail" or "train" of covert feathers, which they display as part of a courtship ritual. The functions of the elaborate iridescent colouration and large "train" of peacocks have been the subject of extensive scientific debate. Charles Darwin suggested they served to attract females, the showy features of the males had evolved by sexual selection. More Amotz Zahavi proposed in his handicap theory that these features acted as honest signals of the males' fitness, since less-fit males would be disadvantaged by the difficulty of surviving with such large and conspicuous structures.
The Indian peacock has iridescent blue and green plumage metallic blue and green, but the green peacock has green and bronze body feathers. In both species, females lack the train and the head ornament; the peacock "tail", known as a "train", consists not of tail quill feathers, but elongated upper tail coverts. These feathers are marked with best seen when a peacock fans his tail. Both sexes of all species have a crest atop the head; the Indian peahen has a mixture of dull grey and green in her plumage. The female displays her plumage to ward off female competition or signal danger to her young. Green peafowl differ from Indian peafowl in that the male has green and gold plumage and black wings with a sheen of blue. Unlike Indian peafowl, the green peahen is similar to the male, only having shorter upper tail coverts, a more coppery neck, overall less iridescence; the Congo peacock male does not display his covert feathers, but uses his actual tail feathers during courtship displays. These feathers are much shorter than those of the Indian and green species, the ocelli are much less pronounced.
Females of the Indian and African species brown. Chicks of both sexes in all the species are cryptically coloured, they vary between yellow and tawny with patches of darker brown or light tan and "dirty white" ivory. Hybrids between Indian and Green peafowl are called Spaldings, after the first person to hybridize them, Mrs. Keith Spalding. Unlike many hybrids, spaldings are fertile and benefit from hybrid vigor. Plumage varies between individual spaldings, with some looking far more like green peafowl and some looking far more like blue peafowl, though most visually carry traits of both. In addition to the wild-type "blue" colouration, several hundred variations in colour and pattern are recognized as separate morphs of the Indian Blue among peafowl breeders. Pattern variations include solid-wing/black shoulder, white-eye, silver pied. colour variations include white, Buford bronze, midnight, charcoal and taupe, as well as the sex-linked colours purple, cameo and Sonja's Violeta. Additional colour and pattern variations are first approved by the United Peafowl Association to become recognized as a morph among breeders.
Alternately-coloured peafowl are born differently coloured than wild-type peafowl, though each colour is recognizable at hatch, their peachick plumage does not match their adult plumage. Peafowl appear with white plumage. Although albino peafowl do exist, this is quite rare, all white peafowl are not albinos. Leucistic peafowl can produce pigment but not deposit the pigment to their feathers; this results in the complete lack of colouration in their blue-grey eye colour. Pied peafowl are affected by partial leucism, where only some pigment cells fail to migrate, resulting in birds that have colour but have patches absent of all colour. By contrast, true albino peafowl would have a complete lack of melanin, resulting in irises that look red or pink. Leucistic peachicks are born yellow and become white as they mature; as with many birds, vibrant iridescent plumage colours are not pigments, but structural colouration. Optical interference Bragg reflections, based on regular, periodic nanostructures of the barbules of the feathers, produce the peacock's colours.
Slight changes to the spacing of these barbules result in different colours. Brown feathers are a mixture of red and blue: one colour is created by the periodic structure and the other is created by a Fabry–Pérot interference peak from reflections from the outer and inner boundaries; such structural colouration causes the iridescence of the peacock's hues. Interference effects depend on light angle rather than actual pigments. Charles Darwin suggested in On the Origin of Species that the peafowl's plumage had evolved through sexual selection, he expanded upon The Descent of Man and Selection in Relation to Sex. The sexual struggle is of two kinds.
An arboretum in a general sense is a botanical collection composed of trees. More a modern arboretum is a botanical garden containing living collections of woody plants and is intended at least in part for scientific study. An arboretum specializing in growing conifers is known as a pinetum. Other specialist arboreta include saliceta and querceta; the term arboretum was first used in an English publication by John Claudius Loudon in 1833 in The Gardener's Magazine but the concept was long-established by then. Related collections include a viticetum. Egyptian Pharaohs cared for them. Hatshepsut's expedition to Punt returned bearing thirty-one live frankincense trees, the roots of which were kept in baskets for the duration of the voyage, it is reported that Hatshepsut had these trees planted in the courts of her Deir el Bahri mortuary temple complex. Arboreta are special places for the cultivation and display of a wide variety of different kinds of trees and shrubs. Many tree collections have been claimed as the first arboretum, in most cases, the term has been applied retrospectively as it did not come into use until the eighteenth century.
Arboreta differ from pieces of woodland or plantations because they are botanically significant collections with a variety of examples rather than just a few kinds. Of course there are many tree collections that are much older than the eighteenth century in different parts of the world; the most important early proponent of the arboretum in the English-speaking transatlantic world was the prolific landscape gardener and writer, John Claudius Loudon who undertook many gardening commissions and published the Gardener's Magazine, Encyclopaedia of Gardening and other major works. Loudon's Arboretum et Fruticetum Britannicum, 8 vols. is the most significant work on the subject in British history and included an account of all trees and shrubs that were hardy in the British climate, an international history of arboriculture, an assessment of the cultural and industrial value of trees and four volumes of plates. Loudon urged that a national arboretum be created and called for arboreta and other systematic collections to be established in public parks, private gardens, country estates and other places.
He regarded the Derby Arboretum as the most important landscape-gardening commission of the latter part of his career because it demonstrated the benefits of a public arboretum. Commenting on Loddiges' famous Hackney Botanic Garden arboretum, begun in 1816, a commercial nursery that subsequently opened free to the public, for educational benefit, every Sunday, Loudon wrote: "The arboretum looks better this season than it has done since it was planted... The more lofty trees suffered from the late high winds, but not materially. We walked round the two outer spirals of this coil of shrubs. There is no garden scene about London so interesting". A plan of Loddiges' arboretum was included in The Encyclopaedia of 1834 edition. Leaves from Loddiges' arboretum and in some instances entire trees, were studiously drawn to illustrate Loudon's encyclopaedic book Arboretum et Fruticetum Britannicum which incorporated drawings from other early botanic gardens and parklands throughout the United Kingdom. One example of an early European tree collection is the Trsteno Arboretum, near Dubrovnik in Croatia.
The date of its founding is unknown, but it was in existence by 1492, when a 15 m span aqueduct to irrigate the arboretum was constructed. The garden was created by the prominent local Gučetić/Gozze family, it suffered two major disasters in the 1990s but its two unique and ancient Oriental Planes remained standing. Udhagamandalam Arboretum, The Nilgiris, IndiaThe arboretum at Ooty was established in 1992 with an aim of conserving native and indigenous trees, it was established during the year 1992 and maintained by Department of Horticulture with Hill Area Development Programme funds. The micro watershed area leading to Ooty lake where the arboretum is now located, had been neglected and the feeder line feeding water to Ooty was contaminated with urban waste and agricultural chemicals; the area is the natural habitats of both indigenous and migratory birds. During the year 2005-2006, it was rehabilated with funds provided by the Hill Area Development Programme by providing permanent fencing, a footpath, other infrastructure facilities.
Both indigenous and exotic tree species are included. The following tree species were planted: Celtis tetrandra, Dillenia pentagyna, Elaeocarpus ferrugineus, Elaeocarpus oblongus, Evodia lunuankenda, Glochidion neilgherrense, Ligustrum perrotetti, Litsaea ligustrina, Litsaea wightiana, Meliosma arnotiana, Meliosma wightii, Michelia champaca, Michelia nilagirica, Pygeum gardneri, Syzygium amothanum, Syzygium montanum, Alnus nepalensis, Viburnum erubescens, Podocarpus wallichianus, Rhodomyrtus tomentosa, Rapanea wightiana, Ternstroemia japonica, Microtropis microc
The Château d'Harcourt, situated in the commune of Harcourt in the Eure département of France, is a masterpiece of medieval architecture. The cradle of the Harcourt family, the castle is one of the best preserved castles in the country and contains the oldest arboretum in France. Although the lords of Harcourt trace their origins to the year 1000, it is only in the second half of the 12th century that the existence of a castle can be proven from historical texts. Robert II d'Harcourt was a companion in the crusade of Richard Lionheart. Harcourts appear among the most important barons of Normandy. Jean II d'Harcourt, for example, was named Marshal of France and accommodated in his residence king Philip III. In 1338, king Philip VI, set up the seigniory of Harcourt, with the Château d'Harcourt forming its principal town; the fortress appears to have been under siege through history. It is only at the time of the Hundred Years' War. In 1418, the castle was claimed by the English, but they were expelled by the counts of Dunois, Eu and Saint-Pol in 1449.
As the war came to a close, the domain returned to the Rieux family starting from the second half of the 16th century, to the powerful Lorraine-Guise family. The French Wars of Religion caused an increase in defensive fortifications in the castle. In 1588, the members of a league occupied the castle. In the 17th century, the castle lost all military interest. With his death, Harcourt was bestowed to the Royal Academy of Agriculture of France. Today, the council general of Eure is the owner, it is thought that the Château d'Harcourt consisted in the beginning of a motte-and-bailey surrounded by a ditch, like many of the other fortresses of the time. In the 12th century, a square stone tower took the place of earlier wooden constructions; the castillar architecture evolved according to the progression of sieges, the rise of its successive owners. In the 13th century the old keep; the bailey was protected by a curtain wall punctuated by nine round towers. Ahead of the curtain wall, a deep ditch, dry most of the time, girdled the structure.
Through the 14th century, the defence of the castle continued to improve. A monumental fortified door, a châtelet, was installed to defend the more exposed of the two entries; the archeries were enlarged to allow firing crossbows. In the 17th century, Marie Françoise de Brancas, wife of Alphonse Henri, Count of Harcourt, undertook to refit the medieval fortress to make it more hospitable. A friend of Madame de Maintenon, she demolished three sides of the polygonal castle and thus opened her apartments to the light. With a similar aim, large rectangular bays were bored and the interior disposition was re-examined; the medieval Château d'Harcourt appears truncated today as the top of the keep was levelled to bring it to the same height as the other buildings. There is no longer any building in the bailey, though a chapel was there formerly; the castle is listed as a monument historique by the French Ministry of Culture. Arboretum d'Harcourt List of castles in France Ministry of Culture database entry for Château d'Harcourt Ministry of Culture photos The Château d'Harcourt A visionary in the trees at Chateau d’Harcourt – how Lois-Gervais Delamarre, survivor of the French revolution, started the amazing arboretum at the chateau
Hyacinthoides non-scripta is a bulbous perennial plant, found in Atlantic areas from north-western Spain to the British Isles, frequently used as a garden plant. It is known in English as the common bluebell or bluebell, a name, used in Scotland to refer to the harebell, Campanula rotundifolia. In spring, H. non-scripta produces a nodding, one-sided inflorescence of 5–12 tubular, sweet-scented violet–blue flowers, with recurved tepals, 3–6 long, basal leaves. H. non-scripta is associated with ancient woodland where it may dominate the understorey to produce carpets of violet–blue flowers in "bluebell woods", but occurs in more open habitats in western regions. It is protected under UK law, in some other parts of its range. A related species, H. hispanica has been introduced to the British Isles and hybridises with H. non-scripta to produce intermediates known as H. × massartiana. Hyacinthoides non-scripta was first described by Carl Linnaeus in his seminal 1753 work Species Plantarum, as a species in the genus Hyacinthus.
The specific epithet non-scriptus means "unlettered" or "unmarked" and was intended to distinguish this plant from the classical hyacinth of Greek mythology. This mythical flower, certainly not the modern hyacinth, sprang up from the blood of the dying prince Hyacinthus, his lover, the god Apollo, shed tears that marked the new flower's petals with the letters "AIAI" as a sign of his grief. In 1803, Johann Centurius von Hoffmannsegg and Johann Heinrich Friedrich Link transferred the species to the genus Scilla, in 1849 Christian August Friedrich Garcke transferred it to the genus Endymion. In 1934, Pierre Chouard transferred the species to its current placement in the genus Hyacinthoides. Scilla was the original Greek name for Drimia maritima; the type species of Hyacinthoides is H. hispanica, while that of Endymion is "Scilla nutans", described by James Edward Smith in English Botany in 1797, but now treated as a synonym of H. non-scripta. Smith had argued that nutans is a more fitting epithet than non-scriptus, which makes no sense once separated from Hyacinthus, but the International Code of Nomenclature for algae and plants requires the oldest name to be used, regardless of meaning.
Common names for Hyacinthoides non-scripta include bluebell, common bluebell, English bluebell, British bluebell, wild hyacinth, wood bell, fairy flower and bell bottle. In Scotland, the term "bluebell" is used for Campanula rotundifolia. Hyacinthoides non-scripta forms a clade with three other species – H. hispanica, H. paivae and H. cedretorum – centred on the Iberian Peninsula. H. paivae is restricted to a small area of north-western Iberia, while H. cedretorum is found in mountainous areas of western North Africa. Within Iberia, H. non-scripta and H. hispanica are geographically separated by the Duero river. The genus contains seven further species distributed further east in the Mediterranean Basin. Hyacinthoides non-scripta is a perennial plant, it produces 3–6 linear leaves, all growing from the base of the plant, each 7–16 millimetres wide. An inflorescence of 5–12 flowers is borne on a stem up to 500 mm tall, which droops towards the tip; each flower is 14–20 mm long, with two bracts at the base, the six tepals are recurved at their tips.
The tepals are violet–blue. The three stamens in the outer whorl are fused to the perianth for more than 75% of their length, bear cream-coloured pollen; the flowers are and sweetly scented. The seeds are black, germinate on the soil surface; the bulbs produce contractile roots. This may explain the absence of H. non-scripta from some thin soils over chalk in South East England, since the bulbs are unable to penetrate into sufficiently deep soils. H. Non-scripta differs from H. hispanica, which occurs as an introduced species in the British Isles, in a number of ways. H. hispanica has paler flowers. The outer stamens are fused with the tepals for less than 75% of their length, the anthers are the same colour as the tepals; these two species are thought to have diverged 8000 years ago. The two species hybridise to produce fertile offspring known as Hyacinthoides × massartiana. Hyacinthoides non-scripta is native to the western parts of Atlantic Europe, from north-western Spain to the Netherlands and the British Isles.
It is found in Belgium, Great Britain, Ireland, the Netherlands and Spain, occurs as a naturalized species in Germany and Romania. It has been introduced into various parts of North America, in both the Pacific Northwest, the Great Lakes region and other parts of the United States. Despite the wide distribution of H. non-scripta, it reaches its greatest densities in the British Isles, where
Acer palmatum known as red emperor maple, palmate maple, Japanese maple or smooth Japanese-maple, is a species of woody plant native to Japan, China, eastern Mongolia, southeast Russia. Many different cultivars of this maple have been selected and they are grown worldwide for their large variety of attractive forms, leaf shapes, spectacular colors. Acer palmatum is a deciduous shrub or small tree reaching heights of 6 to 10 m 16 metres growing as an understory plant in shady woodlands, it may have multiple trunks joining close to the ground. In habit, its canopy takes on a dome-like form when mature; the leaves are 4–12 cm long and wide, palmately lobed with five, seven, or nine acutely pointed lobes. The flowers are produced in small cymes, the individual flowers with five red or purple sepals and five whitish petals; the fruit is a pair of each samara 2 -- 3 cm long with a 6 -- 8 mm seed. The seeds of Acer palmatum and similar species require stratification. In nature, Acer palmatum displays considerable genetic variation, with seedlings from the same parent tree showing differences in such traits as leaf size and color.
Overall form of the tree can vary from upright to weeping. Three subspecies are recognised: Acer palmatum subsp. Palmatum. Leaves small, 4–7 cm wide, with five or seven lobes and double-serrate margins. Lower altitudes throughout southern Japan. Acer palmatum subsp. Amoenum H. Hara. Leaves larger, 6–12 cm wide, with seven or nine lobes and single-serrate margins. Higher altitudes throughout Japan and South Korea. Acer palmatum subsp. Matsumurae Koidz. Leaves larger, 6–12 cm wide, with seven lobes and double-serrate margins. Higher altitudes throughout Japan. Acer palmatum has been cultivated in Japan for centuries and in temperate areas around the world since the 1800s; the first specimen of the tree reached Britain in 1820. When Swedish doctor-botanist Carl Peter Thunberg traveled in Japan late in the eighteenth century, he secreted out drawings of a small tree that would become synonymous with the high art of oriental gardens, he gave it the species name palmatum after the hand-like shape of its leaves, similar to the centuries-old Japanese names kaede and momiji, references to the'hands' of frogs and babies, respectively.
Japanese horticulturalists have long developed cultivars from maples found in Japan and nearby Korea and China. They have long been a subject in art. Numerous cultivars are popular in Europe and North America, with red-leafed favored, followed by cascading green shrubs with dissected leaves. Preparations from the branches and leaves are used as a treatment in traditional Chinese medicine. Acer palmatum includes hundreds of named cultivars with a variety forms, leaf types and preferred growing conditions. Heights of mature specimens range depending on type; some tolerate sun, but most prefer part shade in hotter climates. All are adaptable and blend well with companion plants; the trees are suitable for borders and ornamental paths because the root systems are compact and not invasive. Many varieties of Acer palmatum are grown in containers. Trees are prone to prefer consistent water conditions. Trees should be mulched with a thick layer of bark. Well-drained soil is essential. Trees do not require or appreciate heavy fertilization and should only be fertilized, preferably using slow-release fertilizer with a 3 to 1 ratio of nitrogen to phosphorus respectively.
Nitrogen lawn fertilizer should be avoided in the immediate vicinity of these trees as excessive nitrogen can cause overly vigorous growth, prone to pathogens. If space is not a constraint, no pruning is necessary. Trees self-prune foliage that doesn't receive enough light, such as internal branches which are overly shaded by its own canopy; some growers prefer to shape their trees artistically or to thin out interior branches to better expose the graceful main branches. The form of the tree without leaves in winter, can be of great interest and can be pruned to highlight this feature. Trees heal after pruning without needing aftercare; this species should not be pruned like a hedge, but instead methodically shaped by choosing individual branches to remove. They can be pruned just to maintain a smaller size to suit a particular location. Acer palmatum can be used as espalier. Over 1,000 cultivars have been chosen for particular characteristics, which are propagated by asexual reproduction most by grafting, but some cultivars can be propagated by budding, tissue culture, or layering.
Some cultivars are not in cultivation in the Western world or have been lost over the generations, but many new cultivars are developed each decade. Cultivars are chosen for phenotypical aspects such as leaf shape and size, leaf color, bark texture and color, growth pattern. Most cultivars are less vigorous and smaller than is typical for the species, but are more interesting t