Plough
Overview
 
The plough or plow (see spelling differences; icon) is a tool
Tool
A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

 used in farming for initial cultivation
Tillage
Tillage is the agricultural preparation of the soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shovelling, picking, mattock work, hoeing, and raking...

 of soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...

 in preparation for sowing seed or planting. It has been a basic instrument for most of recorded history, and represents one of the major advances in agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

. The primary purpose of ploughing is to turn over the upper layer of the soil, bringing fresh nutrients to the surface, while burying weeds and the remains of previous crops, allowing them to break down.
Encyclopedia
The plough or plow (see spelling differences; icon) is a tool
Tool
A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

 used in farming for initial cultivation
Tillage
Tillage is the agricultural preparation of the soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shovelling, picking, mattock work, hoeing, and raking...

 of soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...

 in preparation for sowing seed or planting. It has been a basic instrument for most of recorded history, and represents one of the major advances in agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

. The primary purpose of ploughing is to turn over the upper layer of the soil, bringing fresh nutrients to the surface, while burying weeds and the remains of previous crops, allowing them to break down. It also aerates the soil, and allows it to hold moisture better. In modern use, a ploughed field is typically left to dry out, and is then harrow
Harrow (tool)
In agriculture, a harrow is an implement for breaking up and smoothing out the surface of the soil. In this way it is distinct in its effect from the plough, which is used for deeper tillage. Harrowing is often carried out on fields to follow the rough finish left by ploughing operations...

ed before planting. Modern competitions take place for ploughing enthusiasts like the National Ploughing Championships
National Ploughing Championships
The Irish National Ploughing Championships take place each year in the month of September. The 2012 Championships will be held at Heathpark, New Ross, Co. Wexford. The first inter- county ploughing contest took place in 1931 as a result of an argument between two lifelong friends, Denis Allen of...

 Ploughs were initially pulled by ox
Ox
An ox , also known as a bullock in Australia, New Zealand and India, is a bovine trained as a draft animal. Oxen are commonly castrated adult male cattle; castration makes the animals more tractable...

en, and later in many areas by horse
Horse
The horse is one of two extant subspecies of Equus ferus, or the wild horse. It is a single-hooved mammal belonging to the taxonomic family Equidae. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature into the large, single-toed animal of today...

s (generally draught horse
Draft horse
A draft horse , draught horse or dray horse , less often called a work horse or heavy horse, is a large horse bred for hard, heavy tasks such as ploughing and farm labour...

s) and mule
Mule
A mule is the offspring of a male donkey and a female horse. Horses and donkeys are different species, with different numbers of chromosomes. Of the two F1 hybrids between these two species, a mule is easier to obtain than a hinny...

s. In industrialised countries, the first mechanical means of pulling a plough used steam
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...

-powered (ploughing engines or steam tractor
Steam tractor
A steam tractor is a vehicle powered by a steam engine which is used for pulling.In North America, the term steam tractor usually refers to a type of agricultural tractor powered by a steam engine, used extensively in the late 19th and early 20th centuries.In Great Britain, the term steam tractor...

s), but these were gradually superseded by internal-combustion
Internal combustion engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...

-powered tractor
Tractor
A tractor is a vehicle specifically designed to deliver a high tractive effort at slow speeds, for the purposes of hauling a trailer or machinery used in agriculture or construction...

s. In the past two decade
Decade
A decade is a period of 10 years. The word is derived from the Ancient Greek dekas which means ten. This etymology is sometime confused with the Latin decas and dies , which is not correct....

s plough use has reduced in some areas (where soil damage and erosion are problems), in favour of shallower ploughing and other less invasive tillage
Tillage
Tillage is the agricultural preparation of the soil by mechanical agitation of various types, such as digging, stirring, and overturning. Examples of human-powered tilling methods using hand tools include shovelling, picking, mattock work, hoeing, and raking...

 techniques.

Ploughs are even used under the sea, for the laying of cables
Pipe-and-cable-laying plough
A pipe-and-cable-laying plough is a trenchless method to bury cables or pipes.The machinery is a form of a subsoiler with a single blade. It is used to lay buried services of virtually any description, for drainage, water, electricity, telecommunications, gas supply etc....

, as well as preparing the earth for side-scan sonar
Side-scan sonar
Side-scan sonar is a category of sonar system that is used to efficiently create an image of large areas of the sea floor...

in a process used in oil exploration
Oil exploration
Hydrocarbon exploration is the search by petroleum geologists and geophysicists for hydrocarbon deposits beneath the Earth's surface, such as oil and natural gas...

.

Etymology

In English, as in other Germanic languages
Germanic languages
The Germanic languages constitute a sub-branch of the Indo-European language family. The common ancestor of all of the languages in this branch is called Proto-Germanic , which was spoken in approximately the mid-1st millennium BC in Iron Age northern Europe...

, the plough was traditionally known by other names, e.g. Old English sulh, Old High German
Old High German
The term Old High German refers to the earliest stage of the German language and it conventionally covers the period from around 500 to 1050. Coherent written texts do not appear until the second half of the 8th century, and some treat the period before 750 as 'prehistoric' and date the start of...

 medela, geiza, or huohili, and Old Norse
Old Norse
Old Norse is a North Germanic language that was spoken by inhabitants of Scandinavia and inhabitants of their overseas settlements during the Viking Age, until about 1300....

 arðr, all presumably referring to the scratch plough.

The current word plough also comes from Germanic, but it appears relatively late (it is absent from Gothic
Gothic language
Gothic is an extinct Germanic language that was spoken by the Goths. It is known primarily from the Codex Argenteus, a 6th-century copy of a 4th-century Bible translation, and is the only East Germanic language with a sizable Text corpus...

), and is thought to be a loanword from one of the north Italic languages
Italic languages
The Italic subfamily is a member of the Indo-European language family. It includes the Romance languages derived from Latin , and a number of extinct languages of the Italian Peninsula, including Umbrian, Oscan, Faliscan, and Latin.In the past various definitions of "Italic" have prevailed...

. In these it had different meanings: in Raetic plaumorati (Pliny), and in Latin plaustrum "wagon, cart", plōstrum, plōstellum "cart", and plōxenum, plōximum "cart box".
The name "plough" originates from the Proto-Germanic
Proto-Germanic language
Proto-Germanic , or Common Germanic, as it is sometimes known, is the unattested, reconstructed proto-language of all the Germanic languages, such as modern English, Frisian, Dutch, Afrikaans, German, Luxembourgish, Danish, Norwegian, Icelandic, Faroese, and Swedish.The Proto-Germanic language is...

 *plōguz ~ *plōgaz. According to a questionable etymology, the root of that word comes from the PIE
Proto-Indo-European language
The Proto-Indo-European language is the reconstructed common ancestor of the Indo-European languages, spoken by the Proto-Indo-Europeans...

 stem *blōkó-, in which case it would be cognate to Armenian
Armenian language
The Armenian language is an Indo-European language spoken by the Armenian people. It is the official language of the Republic of Armenia as well as in the region of Nagorno-Karabakh. The language is also widely spoken by Armenian communities in the Armenian diaspora...

 pelem "to dig" and Welsh
Welsh language
Welsh is a member of the Brythonic branch of the Celtic languages spoken natively in Wales, by some along the Welsh border in England, and in Y Wladfa...

 bwlch "crack". *Plōguz could actually be borrowed from the Proto-Slavic
Proto-Slavic language
Proto-Slavic is the proto-language from which Slavic languages later emerged. It was spoken before the seventh century AD. As with most other proto-languages, no attested writings have been found; the language has been reconstructed by applying the comparative method to all the attested Slavic...

 *plōgu "plough", which gave plugǔ in Old Slavonic.

History of the plough

Hoeing

When agriculture was first developed, simple hand-held digging stick
Digging stick
In archaeology and anthropology a digging stick is the term given to a variety of wooden implements used primarily by subsistence-based cultures to dig out underground food such as roots and tubers or burrowing animals and anthills...

s or hoe
Hoe (tool)
A hoe is an ancient and versatile agricultural tool used to move small amounts of soil. Common goals include weed control by agitating the surface of the soil around plants, piling soil around the base of plants , creating narrow furrows and shallow trenches for planting seeds and bulbs, to chop...

s would have been used in highly fertile areas, such as the banks of the Nile
Nile
The Nile is a major north-flowing river in North Africa, generally regarded as the longest river in the world. It is long. It runs through the ten countries of Sudan, South Sudan, Burundi, Rwanda, Democratic Republic of the Congo, Tanzania, Kenya, Ethiopia, Uganda and Egypt.The Nile has two major...

 where the annual flood rejuvenates the soil, to create furrows wherein seeds could be sown. To grow crops regularly in less fertile areas, the soil must be turned to bring nutrients to the surface. The first people known to plough were the Sumerians.

Scratch plough

The domestication of ox
Ox
An ox , also known as a bullock in Australia, New Zealand and India, is a bovine trained as a draft animal. Oxen are commonly castrated adult male cattle; castration makes the animals more tractable...

en in Mesopotamia
Mesopotamia
Mesopotamia is a toponym for the area of the Tigris–Euphrates river system, largely corresponding to modern-day Iraq, northeastern Syria, southeastern Turkey and southwestern Iran.Widely considered to be the cradle of civilization, Bronze Age Mesopotamia included Sumer and the...

 and by its contemporary Indus valley civilization
Indus Valley Civilization
The Indus Valley Civilization was a Bronze Age civilization that was located in the northwestern region of the Indian subcontinent, consisting of what is now mainly modern-day Pakistan and northwest India...

, perhaps as early as the 6th millennium BC, provided mankind with the pulling power necessary to develop the plough. The very earliest plough was the simple scratch-plough, or ard, which consists of a frame holding a vertical wooden stick that was dragged through the topsoil (still used in many parts of the world). It breaks up a strip of land directly along the ploughed path, which can then be planted. Because this form of plough leaves a strip of undisturbed earth between the rows, fields are often cross-ploughed at 90 degree angles, and this tends to lead to squarish fields. In the archaeology of northern Europe, such squarish fields are referred to as "Celtic fields
Celtic fields
Celtic field is a popular name for the traces of early agricultural field systems found in North-West Europe, e.g. Belgium, Britain, Germany, Ireland and the Netherlands. The name was given by O.G.S. Crawford. They are sometimes preserved in areas where industrial farming has not been adopted and...

".

Crooked ploughs

The Greeks apparently introduced the next major advance in plough design; the crooked plough, which angled the cutting surface forward, leading to the name. The cutting surface was often faced with bronze or (later) iron. Metal was expensive, so in times of war it was melted down or forged to make weapons—or the reverse in more peaceful times. This is presumably the origin of the expression found in the Bible "beat your swords to ploughshares
Swords to ploughshares
Swords to ploughshares is a concept in which military weapons or technologies are converted for peaceful civilian applications....

".

Moldboard plough

A major advance in plough design was the moldboard plough (American spelling: moldboard plow), which aided the cutting blade. The coulter, knife or skeith cuts vertically into the ground just ahead of the share (or frog) a wedge-shaped surface to the front and bottom of the moldboard with the landside of the frame supporting the below-ground components. The upper parts of the frame carry (from the front) the coupling for the motive power (horses), the coulter and the landside frame. Depending on the size of the implement, and the number of furrows it is designed to plough at one time, there is a wheel or wheels positioned to support the frame. In the case of a single-furrow plough there is only one wheel at the front and handles at the rear for the ploughman to steer and manoeuvre it.

When dragged through a field the coulter cuts down into the soil and the share cuts horizontally from the previous furrow to the vertical cut. This releases a rectangular strip of sod that is then lifted by the share and carried by the moldboard up and over, so that the strip of sod (slice of the topsoil
Topsoil
Topsoil is the upper, outermost layer of soil, usually the top to . It has the highest concentration of organic matter and microorganisms and is where most of the Earth's biological soil activity occurs.-Importance:...

) that is being cut lifts and rolls over as the plough moves forward, dropping back to the ground upside down into the furrow and onto the turned soil from the previous run down the field. Each gap in the ground where the soil has been lifted and moved across (usually to the right) is called a furrow. The sod that has been lifted from it rests at about a 45 degree angle in the next-door furrow and lies up the back of the sod from the previous run.

In this way, a series of ploughing runs down a field leaves a row of sods that lie partly in the furrows and partly on the ground lifted earlier. Visually, across the rows, there is the land (unploughed part) on the left, a furrow (half the width of the removed strip of soil) and the removed strip almost upside-down lying on about half of the previous strip of inverted soil, and so on across the field. Each layer of soil and the gutter it came from forms the classic furrow.

The moldboard plough greatly reduced the amount of time needed to prepare a field, and as a consequence, allowed a farmer to work a larger area of land. In addition, the resulting pattern of low (under the moldboard) and high (beside it) ridges in the soil forms water channels, allowing the soil to drain. In areas where snow buildup is an issue, this allows the soil to be planted earlier as the snow runoff is drained away more quickly.
There are five major parts of a moldboard plough:
  1. moldboard
  2. Share
  3. Landside
  4. Frog
  5. Tailpiece


A runner extending from behind the share to the rear of the plough controls the direction of the plough, because it is held against the bottom land-side corner of the new furrow being formed. The holding force is the weight of the sod, as it is raised and rotated, on the curved surface of the moldboard. Because of this runner, the moldboard plough is harder to turn around than the scratch plough, and its introduction brought about a change in the shape of fields—from mostly square fields into longer rectangular "strips" (hence the introduction of the furlong
Furlong
A furlong is a measure of distance in imperial units and U.S. customary units equal to one-eighth of a mile, equivalent to 220 yards, 660 feet, 40 rods, or 10 chains. The exact value of the furlong varies slightly among English-speaking countries....

).

An advance on the basic design was the iron ploughshare, a replaceable horizontal cutting surface mounted on the tip of the share. The earliest ploughs with a detachable and replaceable share date from around 1000 BC in the Ancient Near East
Ancient Near East
The ancient Near East was the home of early civilizations within a region roughly corresponding to the modern Middle East: Mesopotamia , ancient Egypt, ancient Iran The ancient Near East was the home of early civilizations within a region roughly corresponding to the modern Middle East: Mesopotamia...

, and the earliest iron ploughshares from ca. 500 BC in China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

. Early moldboards were basically wedges that sat inside the cut formed by the coulter, turning over the soil to the side. The ploughshare spread the cut horizontally below the surface, so when the moldboard lifted it, a wider area of soil was turned over. moldboards are known in Britain from the late 6th century on.

Loy ploughing

Loy ploughing was a form of manual ploughing which took place in Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

 on very small farms or on very hilly ground, where horses could not work or where farmers could not afford them. It was used up until the 1960s in poorer land. This suited the moist climate of Ireland as the trenches formed by turning in the sods providing drainage. It also allowed the growing of potatoes in bogs as well as on mountain slopes where no other cultivation could take place.

Heavy ploughs

In the basic mouldboard plough the depth of the cut is adjusted by lifting against the runner in the furrow, which limited the weight of the plough to what the ploughman could easily lift. This limited the construction to a small amount of wood (although metal edges were possible). These ploughs were fairly fragile, and were not suitable for breaking up the heavier soils of northern Europe. The introduction of wheels to replace the runner allowed the weight of the plough to increase, and in turn allowed the use of a much larger mouldboard faced in metal. These heavy ploughs led to greater food production and eventually a significant population increase around 600 AD.

Before the Han Dynasty
Han Dynasty
The Han Dynasty was the second imperial dynasty of China, preceded by the Qin Dynasty and succeeded by the Three Kingdoms . It was founded by the rebel leader Liu Bang, known posthumously as Emperor Gaozu of Han. It was briefly interrupted by the Xin Dynasty of the former regent Wang Mang...

 (202 BC–220 AD), Chinese ploughs were made almost entirely of wood, spare the iron blade of the ploughshare. By the Han period, the entire ploughshare was made of cast iron
Cast iron
Cast iron is derived from pig iron, and while it usually refers to gray iron, it also identifies a large group of ferrous alloys which solidify with a eutectic. The color of a fractured surface can be used to identify an alloy. White cast iron is named after its white surface when fractured, due...

; these are the first known heavy moldboard iron ploughs.

The Romans achieved the heavy wheeled mouldboard plough in the late 3rd and 4th century AD, when archaeological evidence appears, inter alia, in Roman Britain
Roman Britain
Roman Britain was the part of the island of Great Britain controlled by the Roman Empire from AD 43 until ca. AD 410.The Romans referred to the imperial province as Britannia, which eventually comprised all of the island of Great Britain south of the fluid frontier with Caledonia...

. The first indisputable appearance after the Roman period is from 643, in a northern Italian document. Old words connected with the heavy plough and its use appear in Slavic
Slavic languages
The Slavic languages , a group of closely related languages of the Slavic peoples and a subgroup of Indo-European languages, have speakers in most of Eastern Europe, in much of the Balkans, in parts of Central Europe, and in the northern part of Asia.-Branches:Scholars traditionally divide Slavic...

, suggesting possible early use in this region. The general adoption of the mouldboard plough in Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

 appears to have accompanied the adoption of the three-field system in the later eighth and early ninth centuries, leading to an improvement of the agricultural productivity per unit of land in northern Europe.

Research by the French historian Marc Bloch
Marc Bloch
Marc Léopold Benjamin Bloch was a French historian who cofounded the highly influential Annales School of French social history. Bloch was a quintessential modernist. An assimilated Alsatian Jew from an academic family in Paris, he was deeply affected in his youth by the Dreyfus Affair...

 in medieval French agricultural history showed the existence of names for two different ploughs, "the araire was wheel-less and had to be dragged across the fields, while the charrue was mounted on wheels".

Improved designs

The basic plough with coulter, ploughshare and mouldboard remained in use for a millennium. Major changes in design did not become common until the Age of Enlightenment
Age of Enlightenment
The Age of Enlightenment was an elite cultural movement of intellectuals in 18th century Europe that sought to mobilize the power of reason in order to reform society and advance knowledge. It promoted intellectual interchange and opposed intolerance and abuses in church and state...

, when there was rapid progress in design. Joseph Foljambe in Rotherham
Rotherham
Rotherham is a town in South Yorkshire, England. It lies on the River Don, at its confluence with the River Rother, between Sheffield and Doncaster. Rotherham, at from Sheffield City Centre, is surrounded by several smaller settlements, which together form the wider Metropolitan Borough of...

, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

, in 1730 used new shapes as the basis for the Rotherham plough, which also covered the mouldboard with iron. Unlike the heavy plough, the Rotherham (or Rotherham swing) plough consisted entirely of the coulter, mouldboard and handles. It was much lighter than conventional designs and became very popular in England. It may have been the first plough to be widely built in factories.

James Small
James Small (inventor)
James Small was a Scottish inventor instrumental in the invention of the modern-style iron swing plough in 1784.-References:...

 further improved the design. Using mathematical methods he experimented with various designs until he arrived at a shape cast from a single piece of iron, the Scots plough. A single-piece cast iron plough was also developed and patented by Charles Newbold
Charles Newbold
Charles Newbold was an American blacksmith born in 1780 in Chesterfield, New Jersey. On June 26, 1797, Newbold received the first patent for a cast iron plow. However, he was unable to sell his plow because many farmers feared that the iron in it would poison the soil...

 in the United States. This was again improved on by Jethro Wood, a blacksmith of Scipio, New York, who made a three-part Scots Plough that allowed a broken piece to be replaced. In 1837 John Deere introduced the first steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 plough; it was so much stronger than iron designs that it was able to work the soil in areas of the US that had previously been considered unsuitable for farming. Improvements on this followed developments in metallurgy; steel coulters and shares with softer iron mouldboards to prevent breakage, the chilled plough which is an early example of surface-hardened
Case hardening
Case hardening or surface hardening is the process of hardening the surface of a metal, often a low carbon steel, by infusing elements into the material's surface, forming a thin layer of a harder alloy...

 steel, and eventually the face of the mouldboard grew strong enough to dispense with the coulter.

Single-sided ploughing

The first mouldboard ploughs could only turn the soil over in one direction (convention
Convention (norm)
A convention is a set of agreed, stipulated or generally accepted standards, norms, social norms or criteria, often taking the form of a custom....

ally always to the right), as dictated by the shape of the mouldboard, and so the field had to be ploughed in long strips, or lands. The plough was usually worked clockwise around each land, ploughing the long sides and being dragged across the short sides without ploughing. The length of the strip was limited by the distance oxen (or later horses) could comfortably work without a rest, and their width by the distance the plough could conveniently be dragged. These distances determined the traditional size of the strips: a furlong
Furlong
A furlong is a measure of distance in imperial units and U.S. customary units equal to one-eighth of a mile, equivalent to 220 yards, 660 feet, 40 rods, or 10 chains. The exact value of the furlong varies slightly among English-speaking countries....

, (or "furrow's length", 220 yards (201.2 m)) by a chain (22 yards (20.1 m))—an area of one acre (about 0.4 hectares); this is the origin of the acre
Acre
The acre is a unit of area in a number of different systems, including the imperial and U.S. customary systems. The most commonly used acres today are the international acre and, in the United States, the survey acre. The most common use of the acre is to measure tracts of land.The acre is related...

. The one-sided action gradually moved soil from the sides to the centre line of the strip. If the strip was in the same place each year, the soil built up into a ridge, creating the ridge and furrow
Ridge and furrow
Ridge and furrow is an archaeological pattern of ridges and troughs created by a system of ploughing used in Europe during the Middle Ages. The earliest examples date to the immediate post-Roman period and the system was used until the 17th century in some areas. Ridge and furrow topography is...

 topography still seen in some ancient fields.

Turnwrest plough

The turnwrest plough allows ploughing to be done to either side. The mouldboard is removable, turning to the right for one furrow, then being moved to the other side of the plough to turn to the left (the coulter and ploughshare are fixed). In this way adjacent furrows can be ploughed in opposite directions, allowing ploughing to proceed continuously along the field and thus avoiding the ridge and furrow topography.

Reversible plough

The reversible plough has two mouldboard ploughs mounted back-to-back, one turning to the right, the other to the left. While one is working the land, the other is carried upside-down in the air. At the end of each row, the paired ploughs are turned over, so the other can be used. This returns along the next furrow, again working the field in a consistent direction.

Riding and multiple-furrow ploughs

Early steel ploughs, like those for thousands of years prior, were walking ploughs, directed by the ploughman holding onto handles on either side of the plough. The steel ploughs were so much easier to draw through the soil that the constant adjustments of the blade to react to roots or clods was no longer necessary, as the plough could easily cut through them. Consequently it was not long after that the first riding ploughs appeared. On these, wheels kept the plough at an adjustable level above the ground, while the ploughman sat on a seat where he would have earlier walked. Direction was now controlled mostly through the draught team, with levers allowing fine adjustments. This led very quickly to riding ploughs with multiple mouldboards, dramatically increasing ploughing performance.

A single draught horse can normally pull a single-furrow plough in clean light soil, but in heavier soils two horses are needed, one walking on the land and one in the furrow. For ploughs with two or more furrows more than two horses are needed and, usually, one or more horses have to walk on the loose ploughed sod—and that makes hard going for them, and the horse treads the newly ploughed land down. It is usual to rest such horses every half hour for about ten minutes.

Heavy volcanic loam soils, such as are found in New Zealand, require the use of four heavy draught horse
Draft horse
A draft horse , draught horse or dray horse , less often called a work horse or heavy horse, is a large horse bred for hard, heavy tasks such as ploughing and farm labour...

s to pull a double-furrow plough. Where paddocks are more square than long-rectangular it is more economical to have horses four wide in harness than two-by-two ahead, thus one horse is always on the ploughed land (the sod). The limits of strength and endurance of horses made greater than two-furrow ploughs uneconomic to use on one farm.

Amish
Amish
The Amish , sometimes referred to as Amish Mennonites, are a group of Christian church fellowships that form a subgroup of the Mennonite churches...

 farmers tend to use a team of about seven horses or mules when spring ploughing and as Amish farmers often help each other plough, teams are sometimes changed at noon. Using this method about 10 acres (40,468.6 m²) can be ploughed per day in light soils and about 2 acres (8,093.7 m²) in heavy soils.

Steam ploughing

The advent of the mobile steam engine
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...

 allowed steam power to be applied to ploughing from about 1850. In Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, soil conditions were often too soft to support the weight of heavy traction engine
Traction engine
A traction engine is a self-propelled steam engine used to move heavy loads on roads, plough ground or to provide power at a chosen location. The name derives from the Latin tractus, meaning 'drawn', since the prime function of any traction engine is to draw a load behind it...

s. Instead, counterbalanced, wheeled ploughs, known as balance ploughs, were drawn by cables across the fields by pairs of ploughing engines which worked along opposite field edges. The balance plough had two sets of ploughs facing each other, arranged so when one was in the ground, the other set was lifted into the air. When pulled in one direction the trailing ploughs were lowered onto the ground by the tension on the cable. When the plough reached the edge of the field, the opposite cable was pulled by the other engine, and the plough tilted (balanced), putting the other set of shares into the ground, and the plough worked back across the field.

One set of ploughs was right-handed, and the other left-handed, allowing continuous ploughing along the field, as with the turnwrest and reversible ploughs. The man credited with the invention of the ploughing engine and the associated balance plough, in the mid nineteenth century, was John Fowler
John Fowler (agricultural engineer)
John Fowler was an English agricultural engineer who was a pioneer in the use of steam engines for ploughing and digging drainage channels...

, an English agricultural engineer and inventor.

In America the firm soil of the Plains allowed direct pulling with steam tractor
Steam tractor
A steam tractor is a vehicle powered by a steam engine which is used for pulling.In North America, the term steam tractor usually refers to a type of agricultural tractor powered by a steam engine, used extensively in the late 19th and early 20th centuries.In Great Britain, the term steam tractor...

s, such as the big Case
Case Corporation
Case Corporation was a manufacturer of construction and agricultural equipment. In 1999 it merged with New Holland to form CNH Global, a Fiat Group division...

, Reeves or Sawyer Massey breaking engines. Gang ploughs of up to fourteen bottoms were used. Often these big ploughs were used in regiments of engines, so that in a single field there might be ten steam tractors each drawing a plough. In this way hundreds of acres could be turned over in a day. Only steam engines had the power to draw the big units. When internal combustion engine
Internal combustion engine
The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...

s appeared, they had neither the strength nor the ruggedness compared to the big steam tractors. Only by reducing the number of shares could the work be completed.

Stump-jump plough

The Stump-jump plough
Stump-jump plough
The stump-jump plough is a kind of plough invented in South Australia in the late nineteenth century by Richard Bowyer Smith to solve the particular problem of preparing mallee lands for cultivation.-The problem:...

 was an Australian invention of the 1870s, designed to cope with the breaking up of new farming land, that contains many tree stumps and rocks that would be very expensive to remove. The plough uses a moveable weight to hold the ploughshare in position. When a tree stump or other obstruction such as a rock is encountered, the ploughshare is thrown upwards, clear of the obstacle, to avoid breaking the plough's harness or linkage; ploughing can be continued when the weight is returned to the earth after the obstacle is passed.

A simpler system, developed later, uses a concave disc (or a pair of them) set at a large angle to the direction of progress, that uses the concave shape to hold the disc into the soil—unless something hard strikes the circumference of the disk, causing it to roll up and over the obstruction. As the arrangement is dragged forward, the sharp edge of the disc cuts the soil, and the concave surface of the rotating disc lifts and throws the soil to the side. It doesn't make as good a job as the mouldboard plough (but this is not considered a disadvantage, because it helps fight the wind erosion), but it does lift and break up the soil (see disc harrow
Disc harrow
A disc harrow is a farm implement that is used to cultivate the soil where crops are to be planted. It is also used to chop up unwanted weeds or crop remainders. It consists of many iron or steel discs which have slight concavity and are arranged into two or four sections...

).

Modern ploughs

Modern ploughs are usually multiple reversible ploughs, mounted on a tractor
Tractor
A tractor is a vehicle specifically designed to deliver a high tractive effort at slow speeds, for the purposes of hauling a trailer or machinery used in agriculture or construction...

 via a three-point linkage
Three-point hitch
The three-point hitch most often refers to the way ploughs and other implements are attached to an agricultural tractor. The three points resemble either a triangle, or the letter A...

. These commonly have between two and as many as seven mouldboards—and semi-mounted ploughs (the lifting of which is supplemented by a wheel about half-way along their length) can have as many as eighteen mouldboards. The hydraulic system of the tractor is used to lift and reverse the implement, as well as to adjust furrow width and depth. The ploughman still has to set the draughting linkage from the tractor so that the plough is carried at the proper angle in the soil. This angle and depth can be controlled automatically by modern tractors. As a complement to the rear plough a two or three mouldboards-plough can be mounted on the front of the tractor if it is equipped with front three-point linkage.

Chisel plough

The chisel plough is a common tool to get deep tillage (prepared land) with limited soil disruption. The main function of this plough is to loosen and aerate the soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...

s while leaving crop residue at the top of the soil. This plough can be used to reduce the effects of compaction
Soil compaction
In Geotechnical engineering, soil compaction is the process in which a stress applied to a soil causes densification as air is displaced from the pores between the soil grains. When stress is applied that causes densification due to water being displaced from between the soil grains then...

 and to help break up ploughpan and hardpan
Hardpan
In soil science, agriculture and gardening, hardpan or ouklip is a general term for a dense layer of soil, usually found below the uppermost topsoil layer. There are different types of hardpan, all sharing the general characteristic of being a distinct soil layer that is largely impervious to water...

. Unlike many other ploughs the chisel will not invert or turn the soil. This characteristic has made it a useful addition to no-till
No-till farming
No-till farming is a way of growing crops from year to year without disturbing the soil through tillage. No-till is an agricultural technique which increases the amount of water and organic matter in the soil and decreases erosion...

 and low-till farming practices which attempt to maximise the erosion-prevention benefits of keeping organic matter and farming residues present on the soil surface through the year. Because of these attributes, the use of a chisel plough is considered by some to be more sustainable
Sustainable agriculture
Sustainable agriculture is the practice of farming using principles of ecology, the study of relationships between organisms and their environment...

 than other types of plough, such as the mouldboard plough.
The chisel plough is typically set to run up to a depth of eight to twelve inches (200 to 300 mm). However some models may run much deeper. Each of the individual ploughs, or shanks, are typically set from nine inches (229 mm) to twelve inches (305 mm) apart. Such a plough can encounter significant soil drag, consequently a tractor
Tractor
A tractor is a vehicle specifically designed to deliver a high tractive effort at slow speeds, for the purposes of hauling a trailer or machinery used in agriculture or construction...

 of sufficient power
Motive power
In thermodynamics, motive power is an agency, as water or steam, used to impart motion. Generally, motive power is defined as a natural agent, as water, steam, wind, electricity, etc., used to impart motion to machinery; a motor; a mover. The term may also define something, as a locomotive or a...

 and good traction is required. When planning to plough with a chisel plough it is important to bear in mind that 10 to 15 horsepower
Horsepower
Horsepower is the name of several units of measurement of power. The most common definitions equal between 735.5 and 750 watts.Horsepower was originally defined to compare the output of steam engines with the power of draft horses in continuous operation. The unit was widely adopted to measure the...

 (7 to 11 kW) per shank will be required.

Cultivator
Cultivator
A cultivator is any of several types of farm implement used for secondary tillage. One sense of the name refers to frames with teeth that pierce the soil as they are dragged through it linearly. Another sense refers to machines that use rotary motion of disks or teeth to accomplish a similar result...

s are often similar in form to chisel ploughs, but their goals are different. Cultivator teeth work near the surface, usually for weed control, whereas chisel plough shanks work deep beneath the surface. Consequently, cultivating also takes much less power per shank than does chisel ploughing.

Ridging plough

A ridging plough is used for crops, such as potato
Potato
The potato is a starchy, tuberous crop from the perennial Solanum tuberosum of the Solanaceae family . The word potato may refer to the plant itself as well as the edible tuber. In the region of the Andes, there are some other closely related cultivated potato species...

es or scallion
Scallion
Scallions , are the edible plants of various Allium species, all of which are "onion-like", having hollow green leaves and lacking a fully developed root bulb.-Etymology:The words...

s, which are grown buried in ridges of soil using a technique called ridging or hilling
Hilling
Hilling, earthing up or ridging is the technique in agriculture and horticulture of piling soil up around the base of a plant. It can be done by hand , or with powered machinery, typically a tractor attachment....

. A ridging plough has two mouldboards facing away from each other, cutting a deep furrow on each pass, with high ridges either side. The same plough may be used to split the ridges to harvest the crop.

Scottish hand plough

This is a variety of ridge plough notable in that the blade points towards the operator. It is used solely by human effort rather than with animal or machine assistance, and is pulled backwards by the operator, requiring great physical effort. It is particularly used for second breaking of ground, and for potato planting. It is found in Shetland, some western crofts and more rarely Central Scotland. The tool is typically found on small holdings too small or poor to merit use of animals.

Mole plough

The mole plough or subsoiler allows underdrainage to be installed without trenches, or it breaks up deep impermeable soil layers which impede drainage. It is a very deep plough, with a torpedo-shaped or wedge-shaped tip, and a narrow blade connecting this to the body. When dragged through the ground, it leaves a channel deep under the ground, and this acts as a drain. Modern mole ploughs may also bury a flexible perforated plastic drain pipe as they go, making a more permanent drain—or they may be used to lay pipes for water supply or other purposes.

Advantages of the mouldboard plough

Mouldboard ploughing, in cold and temperate climates, no deeper than 20 cm, aerates the soil by loosening it. It incorporates crop residues, solid manures, limestone and commercial fertilizers along with some oxygen. By doing so, it reduces nitrogen losses by volatilization, accelerates mineralization and increases short-term nitrogen availability for transformation of organic matter into humus. It erases wheel tracks and ruts caused by harvesting equipment. It controls many perennial weeds and pushes back the growth of other weeds until the following spring. It accelerates soil warming and water evaporation in spring because of the lesser quantity of residues on the soil surface. It facilitates seeding with a lighter seeder. It controls many enemies of crops (slugs, crane flies, seedcorn maggots-bean seed flies, borers). It increases the number of "soil-eating" earthworms (endogea) but is detrimental to vertical-dwelling earthworms (anecic).

Disadvantages of the mouldboard plough

Over-ploughing can lead to the formation of hardpan
Hardpan
In soil science, agriculture and gardening, hardpan or ouklip is a general term for a dense layer of soil, usually found below the uppermost topsoil layer. There are different types of hardpan, all sharing the general characteristic of being a distinct soil layer that is largely impervious to water...

. Typically farmers break up hardpan up with a subsoiler
Subsoiler
A subsoiler or mole plough is a tractor mounted implement used to loosen and break up soil at depths below the level of a traditional disk harrow or rototiller. Most tractor mounted cultivation tools will break up and turn over surface soil to a depth of 6" to 8" while a subsoiler will break up...

, which acts as a long, sharp knife to slice through the hardened layer of soil deep below the surface. Soil erosion due to improper land and plough utilization is possible. Contour ploughing
Contour plowing
Contour plowing or contour farming is the farming practice of plowing across a slope following its elevation contour lines. The rows formed slow water run-off during rainstorms to prevent soil erosion and allow the water time to settle into the soil...

 mitigates soil erosion by ploughing across a slope, along elevation lines. Alternatives to ploughing, such as the no till method, have the potential to actually build soil levels and humus, and may be suitable to smaller, more intensively cultivated plots, and to farming on poor, shallow or degraded soils which will only be further damaged by ploughing.

Plough parts

The picture to the right illustrates the following parts of a plough (numbering matches parts on the image):
  1. Frame
  2. Three point attach
  3. Height regulator
  4. Knife or coulter
    Coulter (Agriculture)
    A coulter is a component of many plows which consists of a vertically mounted knife-like blade. It cuts down into the soil ahead of the plowshare, softening the dirt and allowing the plow to undercut the furrow made by the coulter....

  5. Chisel
  6. Share
    Plowshare
    In agriculture, a plowshare is a component of a plow . It is the cutting or leading edge of a moldboard which closely follows the coulter when plowing....

    , also called the ploughshare
  7. Mouldboard
  8. Plough shaft

Other portions include the frog, runner, landside, shin, trashboard and handles.

On modern ploughs and some older ploughs, the mouldboard is separate from the share and runner, allowing these parts to be replaced without replacing the mouldboard. Abrasion eventually destroys all parts of a plough that contact the soil.

See also

  • Aratrum
    Aratrum
    Aratrum is the Latin word for plough, and "arotron" is the Greek word. The Greeks appear to have had diverse kinds of plough from the earliest historical records. Hesiod advised the farmer to have always two ploughs, so that if one broke the other might be ready for use...

    —Ancient Greek and Roman plough
  • Ard (plough)—Scratch plough
  • Boustrephedon (Greek
    Greek language
    Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...

    : "ox-turning")—An ancient way of writing, each line being read in the opposite direction like reversible ploughing.
  • Foot plough
    Foot plough
    The foot plough is a type of spade used for cultivation, in the north west of Scotland. The Scottish Gaelic language contains many terms for the various varieties, e.g. cas-dhìreach for the straighter variety and on, but cas-chrom is the most common variety and refers to the crooked spade...

  • Headland (agriculture)
    Headland (agriculture)
    In agriculture, a headland is the area at each end of a planted field. It is used for turning around with farm implements during field operations and is the first area to be harvested to minimize crop damage...

  • History of agriculture
    History of agriculture
    Agriculture was developed at least 10,000 years ago, and it has undergone significant developments since the time of the earliest cultivation. The Fertile Crescent of Western Asia, Egypt, and India were sites of the earliest planned sowing and harvesting of plants that had previously been gathered...

  • John Deere
    John Deere
    John Deere was an American blacksmith and manufacturer who founded Deere & Company, one of the largest and leading agricultural and construction equipment manufacturers in the world...

  • Museum of Scottish Country Life
  • Railroad plough
    Railroad plough
    A railroad plough is a rail vehicle which supports an immensely strong, hook-shaped 'plough'...

  • Ridge and furrow
    Ridge and furrow
    Ridge and furrow is an archaeological pattern of ridges and troughs created by a system of ploughing used in Europe during the Middle Ages. The earliest examples date to the immediate post-Roman period and the system was used until the 17th century in some areas. Ridge and furrow topography is...

  • Snowplough
    Snowplow
    A snowplow is a device intended for mounting on a vehicle, used for removing snow and ice from outdoor surfaces, typically those serving transportation purposes...

  • Sokha
    Sokha
    In the region of Russia, a sokha was a light wooden plough which could be pulled by one horse. The historic sources show that it was in use in Russia at least since the 13th century. Its origin was in north Russia, for example Novgorod...

    —Old Russian scratch-plough
  • Whippletree
    Whippletree (mechanism)
    A whippletree or whiffletree is a mechanism to distribute force evenly through linkages. The mechanism may also be referred to as an equalizer, leader bar or double tree. It consists of a bar pivoted at or near the centre, with force applied from one direction to the pivot, and from the other...


Further reading

  • Nanchinadu: Harbinger of Rice and Plough Culture in the Ancient World by Dr. V. Sankaran Nair

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK