Pollarding, a pruning system involving the removal of the upper branches of a tree, promotes a dense head of foliage and branches. In ancient Rome, Propertius mentioned pollarding during the 1st century BCE; the practice occurred in Europe since medieval times, takes place today in urban areas worldwide to maintain trees at a determined height. Traditionally, people pollarded trees for one of two reasons: for fodder to feed livestock or for wood. Fodder pollards produced "pollard hay" for livestock feed. Wood pollards were pruned at longer intervals of eight to fifteen years, a pruning cycle tending to produce upright poles favored for fence rails and posts and boat construction. Supple young willow or hazel branches may be harvested as material for weaving baskets and garden constructions such as bowers. Nowadays, the practice is sometimes used for ornamental trees, such as crepe myrtles in southern states of the USA, although the resulting tree has a stunted form rather than a natural-looking crown.
Pollarding tends to make trees live longer by maintaining them in a juvenile state and by reducing the weight and windage of the top part of the tree. Older pollards become hollow, so can be difficult to age accurately. Pollards tend to grow with denser growth-rings in the years after cutting. Pollarding began with walled cities in Europe; the smaller limbs that resulted could be used for cooking. As in coppicing, pollarding is to encourage the tree to produce new growth on a regular basis to maintain a supply of new wood for various purposes for fuel. In some areas, dried leafy branches are stored as winter fodder for stock. Depending on the use of the cut material, the length of time between cutting will vary from one year for tree hay or withies, to five years or more for larger timber. Sometimes, only some of the regrown stems may be cut in a season – this is thought to reduce the chances of death of the tree when recutting long-neglected pollards. Pollarding was preferred over coppicing in wood-pastures and other grazed areas, because animals would browse the regrowth from coppice stools.
The right to pollard or "lop" was granted to local people for fuel on common land or in royal forests. An incidental effect of pollarding in woodland is the encouragement of underbrush growth due to increased light reaching the woodland floor; this can increase species diversity. However, in woodland where pollarding was once common but has now ceased, the opposite effect occurs, as the side and top shoots develop into trunk-sized branches. An example of this can be seen in Epping Forest in London/Essex, UK, the majority of, pollarded until the late 19th century. Here, the light that reaches the woodland floor is limited owing to the thick growth of the pollarded trees. Pollards cut at about a metre above the ground are called stubs; these were used as markers in coppice or other woodland. Stubs cannot be used where the trees are browsed by animals, as the regrowing shoots are below the browse line. Although people who migrated to the United States from Europe continued the practice, experts have come to believe that pollarding older trees harms the tree.
The smaller limbs grow from wood, not as strong, the weaker trees will not live as long and can be more damaged by storms. As with coppicing, only species with vigorous epicormic growth may be made into pollards. In these species, removal of the main apical stems releases the growth of many dormant buds under the bark on the lower part of the tree. Trees without this growth will die without their branches; some smaller tree species do not form pollards, because cutting the main stem stimulates growth from the base forming a coppice stool instead. Examples of trees that do well as pollards include broadleaves such as beeches, maples, black locust or false acacia, hornbeams and limes, horse chestnuts, Eastern redbud, tree of heaven, a few conifers, such as yews; the technique is used in Africa for moringa trees to bring the nutritious leaves into easier reach for harvesting. Pollarding is used in urban forestry in certain areas for reasons such as tree size management and health concerns, it removes rotting or diseased branches to support the overall health of the tree and removes living and dead branches that could harm property and people, as well as increasing the amount of foliage in spring for aesthetic and air quality reasons.
Some trees may be rejuvenated by pollarding — for example, Bradford pear, a beautiful flowering species when young that becomes brittle and top-heavy when older. Oaks, when old, can form new trunks from the growth of pollard branches, i.e. surviving branches which have split away from the main branch naturally. "Poll" was a name for the top of the head, "to poll" was a verb meaning "to crop the hair". This use was extended to similar treatment of the horns of animals. A pollard meant someone or something, polled; the noun "pollard" came to be used as a verb: "pollarding". Pollarding has now replaced polling as the verb in the forestry sense. Pollard can be used as an a
Fruit tree forms
Fruit trees are grown in a variety of shapes, sometimes to please the eye but to encourage fruit production. The form or shape of fruit trees can be manipulated by training. Shaping and promoting a particular tree form is done to establish the plant in a particular situation under certain environmental conditions, to increase fruit yield, to enhance fruit quality. For example, pruning a tree to a pyramid shape enables trees to be planted closer together. An open bowl or cup form helps sunlight penetrate the canopy, thus encouraging a high fruit yield whilst keeping the tree short and accessible for harvesting. Other shapes such as cordons and fans offer opportunities for growing trees two dimensionally against walls or fences, or they can be trained to function as barriers; some of the following fruit tree forms require training by tying the branches to the required form. Most require pruning to retain the desired structure. However, not all types of fruit tree are suitable for all forms. An open-centred crown on a short trunk of less than 1 metre.
This is a popular form for apple trees. Bush trees are easy to bear fruit at a young age. Final height is depending on which rootstock is used. Larger than the bush form, with trunks of 2 metres or more. Standard trees can reach a total height of 8 metres, they produce high yields but, being large trees, are not easy to maintain. Similar to the bush form, although the main leader shoot is allowed to maintain its dominance, resulting in a pyramidal shape. A variant of the pyramid form. Designed for dense orchards by Otto Schmitz-Hübsch and Heinrichs in Germany in 1936, this is the most popular training system for dwarf apple and pear trees. Single-stemmed trees planted at an angle, with fruiting spurs encouraged to form along the stem. Any side branches are removed by pruning. Cordons take less space and crop earlier than most other forms, so more varieties can be grown in a given space, but yields are smaller per tree. A special cordon set-up is the Bouché-Thomas system. A central vertical trunk with three or four horizontal branches on each side.
A special espalier in this group is the LePage-system. A short central trunk with several radiating branches growing from the crown. Espaliers with just one tier of horizontal branches 30 cm from the ground; these make a productive border for a vegetable plot. A study on orchard mango trees in Nelspruit, South Africa, compared open vase, closed vase, central leader and standard pruning systems and recommended a modified pyramid, somewhere between a central leader and a closed vase system, for high-density mango orchards; the study evaluated both post-fruit-set and post-harvest pruning, indicating that late mango cultivars benefit from pruning while bearing in late fall, while early cultivars may be best pruned after harvest. Fruit tree pollination Fruit tree propagation Orchards Pruning fruit trees Tree shaping Burvenich, Frederik. Snoei der Fruitbomen
The pear tree and shrub are a species of genus Pyrus, in the family Rosaceae, bearing the pomaceous fruit of the same name. Several species of pear are valued for their edible fruit and juices while others are cultivated as trees; the word pear is from Germanic pera as a loanword of Vulgar Latin pira, the plural of pirum, akin to Greek apios, of Semitic origin, meaning "fruit". The adjective pyriform or piriform means pear-shaped; the pear is native to coastal and mildly temperate regions of the Old World, from western Europe and north Africa east right across Asia. It is a medium-sized tree, reaching 10–17 metres tall with a tall, narrow crown; the leaves are alternately arranged, simple, 2–12 centimetres long, glossy green on some species, densely silvery-hairy in some others. Most pears are deciduous. Most are cold-hardy, withstanding temperatures between −25 °C and −40 °C in winter, except for the evergreen species, which only tolerate temperatures down to about −15 °C; the flowers are white tinted yellow or pink, 2–4 centimetres diameter, have five petals.
Like that of the related apple, the pear fruit is a pome, in most wild species 1–4 centimetres diameter, but in some cultivated forms up to 18 centimetres long and 8 centimetres broad. The fruit is composed of the receptacle or upper end of the flower-stalk dilated. Enclosed within its cellular flesh is the true fruit: five'cartilaginous' carpels, known colloquially as the "core". From the upper rim of the receptacle are given off the five sepals, the five petals, the numerous stamens. Pears and apples cannot always be distinguished by the form of the fruit. One major difference is. Pear cultivation in cool temperate climates extends to the remotest antiquity, there is evidence of its use as a food since prehistoric times. Many traces of it have been found in prehistoric pile dwellings around Lake Zurich; the word “pear”, or its equivalent, occurs in all the Celtic languages, while in Slavic and other dialects, differing appellations, still referring to the same thing, are found—a diversity and multiplicity of nomenclature which led Alphonse Pyramus de Candolle to infer a ancient cultivation of the tree from the shores of the Caspian to those of the Atlantic.
The pear was cultivated by the Romans, who ate the fruits raw or cooked, just like apples. Pliny's Natural History noted three dozen varieties; the Roman cookbook De re coquinaria has a recipe for a spiced, stewed-pear patina, or soufflé. A certain race of pears, with white down on the undersurface of their leaves, is supposed to have originated from P. nivalis, their fruit is chiefly used in France in the manufacture of perry. Other small-fruited pears, distinguished by their early ripening and apple-like fruit, may be referred to as P. cordata, a species found wild in western France and southwestern England. Pears have been cultivated in China for 3000 years; the genus is thought to have originated in present-day Western China in the foothills of the Tian Shan, a mountain range of Central Asia, to have spread to the north and south along mountain chains, evolving into a diverse group of over 20 recognized primary species. The enormous number of varieties of the cultivated European pear, are without doubt derived from one or two wild subspecies distributed throughout Europe, sometimes forming part of the natural vegetation of the forests.
Court accounts of Henry III of England record pears shipped from La Rochelle-Normande and presented to the King by the Sheriffs of the City of London. The French names of pears grown in English medieval gardens suggest that their reputation, at the least, was French. Asian species with medium to large edible fruit include P. pyrifolia, P. ussuriensis, P. × bretschneideri, P. × sinkiangensis, P. pashia. Other small-fruited species are used as rootstocks for the cultivated forms. According to Pear Bureau Northwest, about 3000 known varieties of pears are grown worldwide; the pear is propagated by grafting a selected variety onto a rootstock, which may be of a pear variety or quince. Quince rootstocks produce smaller trees, desirable in commercial orchards or domestic gardens. For new varieties the flowers can be cross-bred to combine desirable traits; the fruit of the pear is produced on spurs. Three species account for the vast majority of edible fruit production, the European pear Pyrus communis subsp.
Communis cultivated in Europe and North America, the Chinese white pear Pyrus ×bretschneideri, the Nashi pear Pyrus pyrifolia, both grown in eastern Asia. There are thousands of cultivars of these three species. A species grown in western China, P. sinkiangensis, P. pashia, grown in southern China and south Asia, are produced to a lesser degree. Other species are used as ornamental trees. Pear wood is close-grained a
Gardening is the practice of growing and cultivating plants as part of horticulture. In gardens, ornamental plants are grown for their flowers, foliage, or overall appearance. Gardening is considered by many people to be a relaxing activity. Gardening ranges in scale from fruit orchards, to long boulevard plantings with one or more different types of shrubs and herbaceous plants, to residential yards including lawns and foundation plantings, to plants in large or small containers grown inside or outside. Gardening may be specialized, with only one type of plant grown, or involve a large number of different plants in mixed plantings, it involves an active participation in the growing of plants, tends to be labor-intensive, which differentiates it from farming or forestry. Forest gardening, a forest-based food production system, is the world's oldest form of gardening. Forest gardens originated in prehistoric times along jungle-clad river banks and in the wet foothills of monsoon regions. In the gradual process of families improving their immediate environment, useful tree and vine species were identified and improved while undesirable species were eliminated.
Foreign species were selected and incorporated into the gardens. After the emergence of the first civilizations, wealthy individuals began to create gardens for aesthetic purposes. Ancient Egyptian tomb paintings from the New Kingdom provide some of the earliest physical evidence of ornamental horticulture and landscape design. A notable example of ancient ornamental gardens were the Hanging Gardens of Babylon—one of the Seven Wonders of the Ancient World —while ancient Rome had dozens of gardens. Wealthy ancient Egyptians used gardens for providing shade. Egyptians associated trees and gardens with gods, believing that their deities were pleased by gardens. Gardens in ancient Egypt were surrounded by walls with trees planted in rows. Among the most popular species planted were date palms, fir trees, nut trees, willows; these gardens were a sign of higher socioeconomic status. In addition, wealthy ancient Egyptians grew vineyards, as wine was a sign of the higher social classes. Roses, poppies and irises could all be found in the gardens of the Egyptians.
Assyria was renowned for its beautiful gardens. These tended to be wide and large, some of them used for hunting game—rather like a game reserve today—and others as leisure gardens. Cypresses and palms were some of the most planted types of trees. Ancient Roman gardens were laid out with hedges and vines and contained a wide variety of flowers—acanthus, crocus, hyacinth, ivy, lilies, narcissus, poppy and violets—as well as statues and sculptures. Flower beds were popular in the courtyards of rich Romans; the Middle Age represented a period of decline in gardens for aesthetic purposes, with regard to gardening. After the fall of Rome, gardening was done for the purpose of growing medicinal herbs and/or decorating church altars. Monasteries carried on a tradition of garden design and intense horticultural techniques during the medieval period in Europe. Monastic garden types consisted of kitchen gardens, infirmary gardens, cemetery orchards, cloister garths and vineyards. Individual monasteries might have had a "green court", a plot of grass and trees where horses could graze, as well as a cellarer's garden or private gardens for obedientiaries, monks who held specific posts within the monastery.
Islamic gardens were built after the model of Persian gardens and they were enclosed by walls and divided in 4 by watercourses. The center of the garden would have a pool or pavilion. Specific to the Islamic gardens are the mosaics and glazed tiles used to decorate the rills and fountains that were built in these gardens. By the late 13th century, rich Europeans began to grow gardens for leisure and for medicinal herbs and vegetables, they surrounded the gardens by walls to provide seclusion. During the next two centuries, Europeans started planting lawns and raising flowerbeds and trellises of roses. Fruit trees were common in these gardens and in some, there were turf seats. At the same time, the gardens in the monasteries were a place to grow flowers and medicinal herbs but they were a space where the monks could enjoy nature and relax; the gardens in the 16th and 17th century were symmetric and balanced with a more classical appearance. Most of these gardens were built around a central axis and they were divided into different parts by hedges.
Gardens had flowerbeds laid out in squares and separated by gravel paths. Gardens in Renaissance were adorned with sculptures and fountains. In the 17th century, knot gardens became popular along with the hedge mazes. By this time, Europeans started planting new flowers such as tulips and sunflowers. Cottage gardens, which emerged in Elizabethan times, appear to have originated as a local source for herbs and fruits. One theory is that they arose out of the Black Death of the 1340s, when the death of so many laborers made land available for small cottages with personal gardens. According to the late 19th-century legend of origin, these gardens were created by the workers that lived in the cottages of the villages, to provide them with food and herbs, with flowers planted among them for decoration. Farm workers were provided with cottages that had architectural quality set in a small garden—about 1 acre —where the
Pruning is a horticultural and silvicultural practice involving the selective removal of certain parts of a plant, such as branches, buds, or roots. Reasons to prune plants include deadwood removal, improving or sustaining health, reducing risk from falling branches, preparing nursery specimens for transplanting, both harvesting and increasing the yield or quality of flowers and fruits; the practice entails targeted removal of diseased, dead, non-productive, structurally unsound, or otherwise unwanted tissue from crop and landscape plants. In general, the smaller the branch, cut, the easier it is for a woody plant to compartmentalize the wound and thus limit the potential for pathogen intrusion and decay, it is therefore preferable to make any necessary formative structural pruning cuts to young plants, rather than removing large, poorly placed branches from mature plants. Specialized pruning practices may be applied to certain plants, such as roses, fruit trees, grapevines, it is important when pruning that the tree’s limbs are kept intact, as this is what helps the tree stay upright.
Different pruning techniques may be deployed on herbaceous plants than those used on perennial woody plants. Hedges, by design, are maintained by hedge trimming, rather than by pruning. In nature, meteorological conditions such as wind and snow, salinity can cause plants to self-prune; this natural shedding is called abscission. For arboricultural purposes the unions of tree branches are placed in one of three types: collared, collarless or codominant. Regardless of the overall type of pruning being carried out, each type of union is cut in a particular way so that the branch has less chance of regrowth from the cut area and best chance of sealing over and compartmentalising decay; this is referred to by arborists as "target cutting". Branches die off for a number of reasons including light deficiency and disease damage, root structure damage. A dead branch will at some point decay back to the parent fall off; this is a slow process but can be quickened by high winds or extreme temperature. The main reason deadwooding is performed is safety.
Situations that demand removal of deadwood is trees that overhang public roads, public areas and gardens. Trees located in wooded areas are assessed as lower risk but assessments consider the number of visitors. Trees adjacent to footpaths and access roads are considered for deadwood removal. Another reason for deadwooding is amenity value, i.e. a tree with a large amount of deadwood throughout the crown looks more aesthetically pleasing with the deadwood removed. The physical practice of deadwooding can be carried out most of the year though not when the tree is coming into leaf; the deadwooding process speeds up the tree's natural abscission process. It reduces unwanted weight and wind resistance and can help overall balance. Crown and canopy thinning increases light and reduces wind resistance by selective removal of branches throughout the canopy of the tree. Crown lifting involves the removal of the lower branches to a given height; the height is achieved by the removal of whole branches or removing the parts of branches which extend below the desired height.
The branches are not lifted to more than one third of the tree's total height. Crown lifting is done for access. Lifting the crown will allow traffic and pedestrians to pass underneath safely; this pruning technique is used in the urban environment as it is for public safety and aesthetics rather than tree form and timber value. Crown lifting introduces light to the lower part of the trunk. To reduce this sometimes smaller branches are left on the lower part of the trunk. Excessive removal of the lower branches can displace the canopy weight, this will make the tree top heavy, therefore adding stress to the tree; when a branch is removed from the trunk, it creates a large wound. This wound is susceptible to disease and decay, could lead to reduced trunk stability. Therefore, much time and consideration must be taken when choosing the height the crown is to be lifted to; this would be an inappropriate operation. This would therefore remove most of the foliage and would largely unbalance the tree; this procedure should not be carried out if the tree is in decline, poor health or dead, dying or dangerous as the operation will remove some of the photosynthetic area the tree uses.
This could lead to death. If the tree is of great importance to an area or town an alternative solution to crown lifting would be to move the target or object so it is not in range. For example, diverting a footpath around a tree’s drip line so the crown lift is not needed. Another solution would be to cable-brace the low hanging branch; this is a non-invasive solution which in some situations can work out more economically and environmentally friendly. Removal of appropriate branches to make the tree structurally sound while shaping it. Selectively pruning a window of view in a tree. Reducing the height and or spread of a tree by selectively cutting back to smaller branches and in fruit trees for increasing of light interception and enhancing fruit quality. A regular form of pruning where certain deciduous species are pruned back to pollard heads every year in the dormant period; this practice is commenced on juvenile trees so they can adapt to the harshness of the practice. Arborists, orchardists, an
Coppicing is a traditional method of woodland management which exploits the capacity of many species of trees to put out new shoots from their stump or roots if cut down. In a coppiced wood, called a copse, young tree stems are cut down to near ground level, known as a stool. New growth emerges and after a number of years, the coppiced tree is harvested and the cycle begins anew. Pollarding is a similar process carried out at a higher level on the tree. Many silviculture practices involve regrowth; the widespread and long-term practice of coppicing as a landscape-scale industry is something that remains of special importance in southern England. Many of the English-language terms referenced in this article are relevant to historic and contemporary practice in that area. A coppiced woodland is harvested in sections or coups on a rotation. In this way, a crop is available each year somewhere in the woodland. Coppicing has the effect of providing a rich variety of habitats, as the woodland always has a range of different-aged coppice growing in it, beneficial for biodiversity.
The cycle length depends upon the species cut, the local custom, the use to which the product is put. Birch can be coppiced for faggots on a three- or four-year cycle, whereas oak can be coppiced over a fifty-year cycle for poles or firewood. Coppicing maintains trees at a juvenile stage, a coppiced tree will never die of old age; the age of a stool may be estimated from its diameter, some are so large—perhaps as much as 5.4 metres across—that they are thought to have been continually coppiced for centuries. Evidence suggests. Coppiced stems are characteristically curved at the base; this curve occurs as the competing stems grow out from the stool in the early stages of the cycle up towards the sky as the canopy closes. The curve may allow the identification of coppice timber in archaeological sites. Timber in the Sweet Track in Somerset has been identified as coppiced lime; the silvicultural system now called coppicing was practiced for small wood production. In German this is called Niederwald.
On in Mediaeval times farmers encouraged pigs to feed from acorns and so some trees were allowed to grow bigger. This different silvicultural system is called in English coppice with standards. In German this is called Mittelwald; as modern forestry seeks to harvest timber mechanically, pigs are no longer fed from acorns, both systems have declined. However, there are cultural and wildlife benefits from these 2 silvicultural systems so both can be found where timber production or some other main forestry purpose is not the sole management objective of the woodland. In the 16th and 17th centuries the technology of charcoal iron production became established in England, continuing in some areas until the late 19th century Along with the growing need for oak bark for tanning, this required large amounts of coppice wood. With this coppice management, wood could be provided for those growing industries in principle indefinitely; this was regulated by a statute of 1544 of Henry VIII, which required woods to be enclosed after cutting and 12 standels to be left in each acre, to be grown into timber.
Coppice with standards has been used throughout most of Europe as a means of giving greater flexibility in the resulting forest product from any one area. The woodland provides not only the small material from the coppice but a range of larger timber for jobs like house building, bridge repair, cart-making and so on. In the 18th century coppicing in Britain began a long decline; this was brought about by the erosion of its traditional markets. Firewood was no longer needed for domestic or industrial uses as coal and coke became obtained and transported, wood as a construction material was replaced by newer materials. Coppicing died out first in the north of Britain and contracted towards the south-east until by the 1960s active commercial coppice was concentrated in Kent and Sussex; the shoots may be used either in their young state for interweaving in wattle fencing or the new shoots may be allowed to grow into large poles, as was the custom with trees such as oaks or ashes. This creates long, straight poles which do not have the bends and forks of grown trees.
Coppicing may be practiced to encourage specific growth patterns, as with cinnamon trees which are grown for their bark. Another, more complicated system is called compound coppice. Here some of the standards would be left; some of the coppice would be allowed to grow into new standards and some regenerated coppice would be there. Thus there would be three age classes. Coppiced hardwoods were used extensively in carriage and shipbuilding, they are still sometimes grown for making wooden buildings and furniture. Withies for wicker-work are grown in coppices of various willow species, principally osier. In France, chestnut trees are coppiced for use as canes and bâtons for the martial art Canne de combat; some Eucalyptus species are coppiced in a number of countries. The Sal tree is coppiced in India, the Moringa oleifera tree is
Evidence, broadly construed, is anything presented in support of an assertion. This support may be weak; the strongest type of evidence is that. At the other extreme is evidence, consistent with an assertion but does not rule out other, contradictory assertions, as in circumstantial evidence. In law, rules of evidence govern the types of evidence. Types of legal evidence include testimony, documentary evidence, physical evidence; the parts of a legal case which are not in controversy are known, in general, as the "facts of the case." Beyond any facts that are undisputed, a judge or jury is tasked with being a trier of fact for the other issues of a case. Evidence and rules are used to decide questions of fact that are disputed, some of which may be determined by the legal burden of proof relevant to the case. Evidence in certain cases must be more compelling than in other situations, which drastically affects the quality and quantity of evidence necessary to decide a case. Scientific evidence consists of observations and experimental results that serve to support, refute, or modify a scientific hypothesis or theory, when collected and interpreted in accordance with the scientific method.
In philosophy, the study of evidence is tied to epistemology, which considers the nature of knowledge and how it can be acquired. The burden of proof is the obligation of a party in an argument or dispute to provide sufficient evidence to shift the other party's or a third party's belief from their initial position; the burden of proof must be fulfilled by both establishing confirming evidence and negating oppositional evidence. Conclusions drawn from evidence may be subject to criticism based on a perceived failure to fulfill the burden of proof. Two principal considerations are: On whom does the burden of proof rest? To what degree of certitude must the assertion be supported? The latter question depends on the nature of the point under contention and determines the quantity and quality of evidence required to meet the burden of proof. In a criminal trial in the United States, for example, the prosecution carries the burden of proof since the defendant is presumed innocent until proven guilty beyond a reasonable doubt.
In most civil procedures, the plaintiff carries the burden of proof and must convince a judge or jury that the preponderance of the evidence is on their side. Other legal standards of proof include "reasonable suspicion", "probable cause", "prima facie evidence", "credible evidence", "substantial evidence", "clear and convincing evidence". In a philosophical debate, there is an implicit burden of proof on the party asserting a claim, since the default position is one of neutrality or unbelief; each party in a debate will therefore carry the burden of proof for any assertion they make in the argument, although some assertions may be granted by the other party without further evidence. If the debate is set up as a resolution to be supported by one side and refuted by another, the overall burden of proof is on the side supporting the resolution. In scientific research evidence is accumulated through observations of phenomena that occur in the natural world, or which are created as experiments in a laboratory or other controlled conditions.
Scientific evidence goes towards supporting or rejecting a hypothesis. The burden of proof is on the person making a contentious claim. Within science, this translates to the burden resting on presenters of a paper, in which the presenters argue for their specific findings; this paper is placed before a panel of judges where the presenter must defend the thesis against all challenges. When evidence is contradictory to predicted expectations, the evidence and the ways of making it are closely scrutinized and only at the end of this process is the hypothesis rejected: this can be referred to as'refutation of the hypothesis'; the rules for evidence used by science are collected systematically in an attempt to avoid the bias inherent to anecdotal evidence. Evidence forms the foundation of a legal system, without which law would be subject to the whims of those with power. In law, the production and presentation of evidence depends first on establishing on whom the burden of proof lies. Admissible evidence is that which a court receives and considers for the purposes of deciding a particular case.
Two primary burden-of-proof considerations exist in law. The first is on. In many Western, the burden of proof is placed on the prosecution in criminal cases and the plaintiff in civil cases; the second consideration is the degree of certitude proof must reach, depending on both the quantity and quality of evidence. These degrees are different for criminal and civil cases, the former requiring evidence beyond a reasonable doubt, the latter considering only which side has the preponderance of evidence, or whether the proposition is more true or false; the decision maker a jury, but sometimes a judge, decides whether the burden of proof has been fulfilled. After deciding who will carry the burden of proof, evidence is first gathered and presented before the court: In criminal investigation, rather than attempting to prove an abstract or hypothetical point, the evidence gatherers attempt to determine, responsible for a criminal act; the focus of criminal evidence is to connect physical evidence and reports of witnesses to a specific person.
The path that physical evidence takes from the scene of a crime or the arrest of a suspect to the courtroom is called the chain of custody. In a criminal case, this path must be cle