|
English Elm
The field elm (''Ulmus minor'') cultivar 'Atinia' , commonly known as the English elm, formerly common elm and horse may, Republished 1978 by EP Publishing, Wakefield. and more lately the Atinian elm, was, before the spread of Dutch elm disease, the most common field elm in central southern England, though not native there, and one of the largest and fastest-growing deciduous trees in Europe. R. H. Richens noted that elm populations exist in north-west Spain, northern Portugal, and on the Mediterranean coast of France that "closely resemble the English elm" and appear to be "trees of long standing" in those regions rather than recent introductions. Augustine Henry had earlier noted that the supposed English elms planted extensively in the Royal Park at Aranjuez from the late 16th century onwards, specimens said to have been introduced from England by Philip IIRichens, R. H., ''Elm'' (Cambridge, 1983), p.276 and "differing in no respects from the English elm in England", be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulmus Minor
''Ulmus minor'' Mill., the field elm, is by far the most polymorphic of the European species, although its taxonomy remains a matter of contention. Its natural range is predominantly south European, extending to Asia Minor and Iran; its northern outposts are the Baltic islands of Öland and Gotland, although it may have been introduced by humans. The tree's typical habitat is low-lying forest along the main rivers, growing in association with oak and ash, where it tolerates summer floods as well as droughts.Heybroek, H. M., Goudzwaard, L, Kaljee, H. (2009). ''Iep of olm, karakterboom van de Lage Landen'' (:Elm, a tree with character of the Low Countries). KNNV, Uitgeverij. Current treatment of the species owes much to Richens, who noted (1983) that several varieties of field elm are distinguishable on the European mainland. Of these, he listed the small-leaved ''U. minor'' of France and Spain; the narrow-leaved ''U. minor'' of northern and central Italy; the densely hairy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diameter At Breast Height
Diameter at breast height, or DBH, is a standard method of expressing the diameter of the trunk or bole of a standing tree. DBH is one of the most common dendrometric measurements. Tree trunks are measured at the height of an adult's breast, which is defined differently in different countries and situations. In many countries, DBH is measured at approximately above ground. Global variation and scientific precision The height can make a substantial difference to the measured diameter. In the United States, DBH is typically measured at above ground. In some countries, such as Australia, New Zealand, Burma, India, Malaysia, and South Africa, breast height diameter has historically been measured at a height of , but because of much active research into allometrics that are being applied to trees and forests, the convention of is more appropriate. Ornamental trees are usually measured at 1.5 metres above ground. Some authors have argued that the term DBH should be abolish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Abertay Dundee
Abertay University () is a public university in the city of Dundee, Scotland. In 1872, Sir David Baxter, 1st Baronet of Kilmaron, left a bequest for the establishment of a mechanics' institute in Dundee and the Dundee Institute of Technology was formed in 1888. As early as 1902 it was recognised by the Scottish Education Department as an educational hub, and was one of the first to be designated a central institution, akin to an "industrial university". Abertay gained university status in 1994. Abertay launched the world's first computer games degree in 1997 and in 2017 held a programme of events celebrating 20 Years of Games. Abertay was also the first to offer a degree in Ethical Hacking, starting in 2006. History The following history to 1988 provides a summary account that relies primarily on the book published by Dundee Institute of Technology in 1989, "The First Hundred Years: 1888–1988". Where additional sources have been used, post 1988, these have been cited accord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetically Engineered
Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesising the DNA. A construct is usually created and used to insert this DNA into the host organism. The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the lambda virus. As well as inserting genes, the process can be used to remove, or "knock out", genes. The new DNA can either be inserted randomly or targeted to a specific part of the genome. An organism that is generated through genetic engineering is considered to be genetically modified ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Powderham Castle
Powderham Castle is a fortified manor house in Exminster, Devon, south of Exeter and mile (0.4 km) north-east of the village of Kenton, where the main public entrance gates are located. It is a Grade I listed building. The park and gardens are Grade II* listed in the National Register of Historic Parks and Gardens. It is on flat ground on the west bank of the River Exe estuary where it is joined by its tributary the River Kenn. On the opposite side of the Exe is the small village of Lympstone. Starting with a structure built sometime after 1390, the present castle was expanded and altered extensively in the 18th and 19th centuries. The castle is the seat of the Courtenay family, Earls of Devon. Origin of the name The manor of Powderham is named from the ancient Dutch word polder, and means "the hamlet of the reclaimed marsh-land". History At some time after 1390 the medieval core of the present structure was built by Sir Philip Courtenay (d. 1406), the 5th or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wych Elm
''Ulmus glabra'', the wych elm or Scots elm, has the widest range of the European elm species, from Ireland eastwards to the Ural Mountains, and from the Arctic Circle south to the mountains of the Peloponnese and Sicily, where the species reaches its southern limit in Europe; it is also found in Iran. A large deciduous tree, it is essentially a montane species, growing at altitudes up to , preferring sites with moist soils and high humidity.Heybroek, H. M., Goudzwaard, L, Kaljee, H. (2009). ''Iep of olm, karakterboom van de Lage Landen'' (:Elm, a tree with character of the Low Countries). KNNV, Uitgeverij. The tree can form pure forests in Scandinavia and occurs as far north as latitude 67°N at Beiarn Municipality in Norway. It has been successfully introduced as far north as Tromsø and Alta in northern Norway (70°N). It has also been successfully introduced to Narsarsuaq, near the southern tip of Greenland ( 61°N). The tree was by far the most common elm in the north ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulmus × Hollandica 'Major'
''Ulmus'' × ''hollandica'' 'Major' is a distinctive cultivar that in England came to be known specifically as ''the'' Dutch Elm, although all naturally occurring Field Elm ''Ulmus minor'' × Wych Elm '' U. glabra'' hybrids are loosely termed 'Dutch elm' ( ''U.'' × ''hollandica''). It is also known by the cultivar name 'Hollandica'. Nellie Bancroft considered 'Major' either an F2 hybrid or a backcrossing with one of its parents.Bancroft, H. 1934. Notes on the status and nomenclature of the British elms. V. – Elms generally accepted as hybrids, the Dutch Elm. ''The Gardeners’ Chronicle'', 96: 298-299. According to Richens the tree was a native of Picardy and elsewhere in northern France, where it was known from the fifteenth to nineteenth centuries as ''ypereau'' or ''ypreau''.Richens, R. H., (1983). ''Elm'' p. 53–54 also 33, 42.Cambridge University Press, 1983), 'Major' was said to have been introduced to England from the Netherlands in the late seventeenth century ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal Shoot
Basal shoots, root sprouts, adventitious shoots, and suckers are words for various kinds of shoots that grow from adventitious buds on the base of a tree or shrub, or from adventitious buds on its roots. Shoots that grow from buds on the base of a tree or shrub are called basal shoots; these are distinguished from shoots that grow from adventitious buds on the roots of a tree or shrub, which may be called root sprouts or suckers. A plant that produces root sprouts or Stolon, runners is described as surculose. Water sprouts produced by adventitious buds may occur on the above-ground stem, branches or both of trees and shrubs. Suckers are shoots arising underground from the roots some distance from the base of a tree or shrub. __TOC__ In botany and ecology In botany, a root sprout or sucker is a severable plant that grows not from a seed but from the meristem of a root at the base of or a certain distance from the original tree or shrub. Root sprouts may emerge a substantial distan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hunsdon
Hunsdon is a village and civil parish in Hertfordshire, England. It is around east of Ware and north-west of Harlow. The population of the village taken at the 2011 Census was 1,080. See also * Baron Hunsdon * Hunsdon Airfield * Hunsdon House *The Hundred Parishes The Hundred Parishes is a cultural heritage initiative focused on an area in the East of England recognized for its high concentration of cultural and historical significance. Although without formal recognition or status, the concept has the ble ... References External linksHunsdon Village Hall {{autho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samara (fruit)
A samara (, ) is a winged achene, a type of fruit in which a flattened wing of fibrous, papery tissue develops from the ovary wall. A samara is a Simple fruit, simple dry fruits, dry fruit, and is Dehiscence (botany), indehiscent (not Dehiscence (botany), opening along a seam). The shape of a samara enables the wind to carry the seed further away from the tree than regular seeds would go, and is thus a form of anemochory. In some cases the seed is in the centre of the wing, as in the elms (genus ''Ulmus''), the hoptree (''Ptelea trifoliata''), and the bushwillows (genus ''Combretum''). In other cases the seed is on one side, with the wing extending to the other side, making the seed autorotation (helicopter), autorotate as it falls, as in the maples (genus ''Acer (plant), Acer'') and ash trees (genus ''Fraxinus''). There are also single-wing samara such as mahogany (genus Swietenia) which have a shape that enables fluttering. Some species that normally produce paired samaras, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf Shape
The following terms are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (that is, the leaf blade or 'lamina' is undivided) or compound (that is, the leaf blade is divided into two or more leaflets). The edge of the leaf may be regular or irregular, and may be smooth or have hair, bristles, or spines. For more terms describing other aspects of leaves besides their overall morphology see the leaf article. The terms listed here all are supported by technical and professional usage, but they cannot be represented as mandatory or undebatable; readers must use their judgement. Authors often use terms arbitrarily, or coin them to taste, possibly in ignorance of established terms, and it is not always clear whether because of ignorance, or personal preference, or because usages change with time or context, or because of variation between specimens, even specimens from the same plant. For example, whether to call leaves on the same tree "ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf
A leaf (: leaves) is a principal appendage of the plant stem, stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the Shoot (botany), shoot system. In most leaves, the primary Photosynthesis, photosynthetic Tissue (biology), tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf, but in some species, including the mature foliage of ''Eucalyptus'', palisade mesophyll is present on both sides and the leaves are said to be isobilateral. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper (Glossary of botanical terms#adaxial, adaxial) and lower (Glossary of botanical terms#abaxial, abaxial) surfaces that differ in color, Trichome, hairiness, the number of stomata (pores that intake and output gases), the amount and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
