Agricultural fencing - AbsoluteAstronomy.com

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...

, fence

Fence

A fence is a freestanding structure designed to restrict or prevent movement across a boundary. It is generally distinguished from a wall by the lightness of its construction: a wall is usually restricted to such barriers made from solid brick or concrete, blocking vision as well as passage .Fences...

s are used to keep animal

Animal

Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

s in or out of an area. They can be made from a wide variety of materials, depending on terrain, location and animals to be confined. Most agricultural fencing averages about 4 feet (1.2 m) high, and in some places, the height and construction of fences designed to hold livestock is mandated by law.

History

Historically throughout most of the world, domesticated

Domestication

Domestication or taming is the process whereby a population of animals or plants, through a process of selection, becomes accustomed to human provision and control. In the Convention on Biological Diversity a domesticated species is defined as a 'species in which the evolutionary process has been...

livestock would roam freely and were fenced out of areas, such as gardens or fields of crops, where they were unwanted. Over time, especially where crop agriculture became dominant and population density of both humans and animals was significant, livestock owners were made to fence their animals in.

The earliest fences were made of available materials, usually stone

Rock (geology)

In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

or wood

Wood

Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

, and these materials are still used for some fences today. In areas where field stones are plentiful, fences have been built up over the years as the stones are removed from fields during tillage and planting of crops. The stones were placed on the field edge to get them out of the way. In time, the piles of stones grew high and wide.

In other areas, fences were constructed of timber

Timber

Timber may refer to:* Timber, a term common in the United Kingdom and Australia for wood materials * Timber, Oregon, an unincorporated community in the U.S...

. Log fences or split-rail fence

Split-rail fence

A split-rail fence or log fence is a type of fence constructed out of timber logs, usually split lengthwise into rails and typically used for agricultural or decorative fencing. Such fences require much more timber than other types of fences, and so are generally only common in areas where wood is...

s were simple fences constructed in newly cleared areas by stacking log rails. Earth could also be used as a fence; an example was what is now called the sunken fence

Ha-ha (garden)

Ha-ha is a term in garden design that refers to a trench, one side of which is concealed from view, designed to allow an unobstructed view from a garden, pleasure-ground, or park, while maintaining a physical barrier in one direction, usually to keep livestock out that are kept on an expansive...

, or "ha-ha," a type of wall built by digging a ditch with one steep side (which animals cannot scale) and one sloped side (where the animals roam).

Fence laws

The tradition of fencing out unwanted livestock prevails even today in some sparsely populated areas. For example, until the mid-20th century, most states in the American West were called "open range" ("fence out") states, in contrast to Eastern and Midwestern states which long had "fence in" laws where livestock must be confined by their owners. Though the open range was part of the western tradition, over time, open range was limited long before it was eliminated completely; first came an obligation to keep cattle from roaming onto state and federal highways, where collisions with fast-moving cars and trucks created a public safety hazard. In addition, voters could voluntarily choose to make certain heavily farmed areas a "herd district," where livestock needed to be fenced in, a process that also became popular in areas where development of hobby farm

Hobby farm

A hobby farm is a smallholding or small farm that is maintained without expectation of being a primary source of income. Some are merely to provide some recreational land, and perhaps a few horses for the family's children...

s created conflicts between large and small landowners. Over time, court cases steadily limited the application of open range law until the present day, where it is the exception rather than the rule in many parts of the American West.

In the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, the law is different for private land and common land

Common land

Common land is land owned collectively or by one person, but over which other people have certain traditional rights, such as to allow their livestock to graze upon it, to collect firewood, or to cut turf for fuel...

. On private land it is the owner's responsibility to fence livestock in, but it is the responsibility of landowners bordering a common to fence the common's livestock out.

Wire fences

The principle of wire fences is that they are supported mainly by tension, being stretched between heavy strut

Strut

A strut is a structural component designed to resist longitudinal compression. Struts provide outwards-facing support in their lengthwise direction, which can be used to keep two other components separate, performing the opposite function of a tie...

ted or guy-wire

Guy-wire

A guy-wire or guy-rope, also known as simply a guy, is a tensioned cable designed to add stability to structures . One end of the cable is attached to the structure, and the other is anchored to the ground at a distance from the structure's base...

d posts at ends, corners, and ideally at intervals in longer stretches (every 50 to 300 metres, 150 to 1000 feet). Between these braced posts are additional smaller wooden or metal posts which keep the wires spaced and upright, usually 3 to 6 metre (10 to 20 feet) apart, depending on the style of fencing used.

Traditionally, wire fencing material is made of galvanized

Galvanization

Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. The term is derived from the name of Italian scientist Luigi Galvani....

mild steel, but galvanized high-tensile steel is now also used in many places. To prevent sagging of the fence, which raises the risk of entanglement or escape, the wire is tensioned as much as the material will safely allow during construction by various means, including a hand-operated "wire stretcher" or "fence stretcher" (called a "monkey strainer" in some areas) or other leverage devices, a winch

Winch

A winch is a mechanical device that is used to pull in or let out or otherwise adjust the "tension" of a rope or wire rope . In its simplest form it consists of a spool and attached hand crank. In larger forms, winches stand at the heart of machines as diverse as tow trucks, steam shovels and...

, or even by carefully pulling with 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...

or other vehicle.

Wire fences are typically run on wooden posts, either from trees commercially grown in plantation

Plantation

A plantation is a long artificially established forest, farm or estate, where crops are grown for sale, often in distant markets rather than for local on-site consumption...

s or (particularly in the American West) cut from public lands. When less expensive or more readily available than wood, steel T-posts or star posts are used, usually alternating every 2 to 5 steel posts with a more stable wood post. Non-electrified wire is attached to wooden posts using fencing staples (for intermediate posts, these are fitted loosely, not gripping the wire). Non-electrified wire is held on T-posts by means of wire "clips" made of smooth galvanized wire that wrap around the back of the post and hook onto the wire on either side of the post.

Other than in a truly desert climate, use of rot-resistant wooden posts or steel posts is advised. In the United States, wood with natural rot resistance, such as oak

Oak

An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...

and juniper

Juniper

Junipers are coniferous plants in the genus Juniperus of the cypress family Cupressaceae. Depending on taxonomic viewpoint, there are between 50-67 species of juniper, widely distributed throughout the northern hemisphere, from the Arctic, south to tropical Africa in the Old World, and to the...

, was often used until it became in short supply in the 1950s. Then, chemically treated pine

Pine

Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...

and spruce

Spruce

A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...

posts became prevalent, and these are also widely used in Britain

United Kingdom

, together with chestnut

Chestnut

Chestnut , some species called chinkapin or chinquapin, is a genus of eight or nine species of deciduous trees and shrubs in the beech family Fagaceae, native to temperate regions of the Northern Hemisphere. The name also refers to the edible nuts they produce.-Species:The chestnut belongs to the...

. Creosote

Creosote

Creosote is the portion of chemical products obtained by the distillation of a tar that remains heavier than water, notably useful for its anti-septic and preservative properties...

, pentachlorophenol

Pentachlorophenol

Pentachlorophenol is an organochlorine compound used as a pesticide and a disinfectant. First produced in the 1930s, it is marketed under many trade names...

, and chromated copper arsenate

Chromated copper arsenate

Chromated copper arsenate is a wood preservative used for timber treatment since the mid-1930s. It is a mix of chromium, copper and arsenic formulated as oxides or salts. It preserves the wood from decay fungi, wood attacking insects, including termites, and marine borers...

are all widely used in the US and elsewhere for treatment (although some of these chemicals are subject to legal controls).

Barbed wire

The Industrial Revolution

Industrial Revolution

The Industrial Revolution was a period from the 18th to the 19th century where major changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times...

brought the first barbed wire

Barbed wire

Barbed wire, also known as barb wire , is a type of fencing wire constructed with sharp edges or points arranged at intervals along the strand. It is used to construct inexpensive fences and is used atop walls surrounding secured property...

(also "barbwire" or just "barb") fences, which were widely used after their introduction in the mid-19th century. This technology made it economically feasible to fence rangeland

Rangeland

Rangelands are vast natural landscapes in the form of grasslands, shrublands, woodlands, wetlands, and deserts. Types of rangelands include tallgrass and shortgrass prairies, desert grasslands and shrublands, woodlands, savannas, chaparrals, steppes, and tundras...

for the first time. In the United States, introduction of barbed wire contributed to the range war

Range war

A range war is a type of conflict that occurs in agrarian or stockrearing societies. Typically fought over water rights or grazing rights to unfenced/unowned land, it could pit competing farmers or ranchers against each other...

s of that century, as various ranch

Ranch

A ranch is an area of landscape, including various structures, given primarily to the practice of ranching, the practice of raising grazing livestock such as cattle or sheep for meat or wool. The word most often applies to livestock-raising operations in the western United States and Canada, though...

interests attempted to use barbed wire fences to claim exclusive access to the best pasture and water resources, including those lands in the public domain

Public domain

Works are in the public domain if the intellectual property rights have expired, if the intellectual property rights are forfeited, or if they are not covered by intellectual property rights at all...

. It also exacerbated tensions between cattle ranchers and crop farmers, partly when access to water was involved.

Barbed wire has been made by many manufacturers in an almost endless variety of styles. For the most part these were functionally identical. The differences reflected peculiarities of each manufacturing process rather than deliberate design of the end product. Sections of unusual barbed wire are collected by some enthusiasts.

The traditional barbed wire used since the late 19th century and into the present day was made from two mild steel wires twisted together, usually of about 12 or 14 gauge, with about 15-30 twists per metre. Steel barbs were attached every 10–20 cm. Barbs had either two or four points, with the two point design using somewhat heavier and longer barbs. The relative merits of two point vs. four point barbed wire are the subject of deeply held views among many farmers and ranchers, to the extent that both types are still made today.

Typically four strands of barbed wire, with the lowest strand no more than 12 inches (304.8 mm) from the ground and the top strand at least 48 inches above the ground, make up a legal fence in the western United States. Better-quality fences have five strands, older fences often had only three strands, and just two strands is widely used in Britain if only adult cattle are being contained. Other variations exist, depending on local laws and the purpose of the fence.

Barbed wire is particularly effective for containing cattle

Cattle

Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...

. In pasture

Pasture

Pasture is land used for grazing. Pasture lands in the narrow sense are enclosed tracts of farmland, grazed by domesticated livestock, such as horses, cattle, sheep or swine. The vegetation of tended pasture, forage, consists mainly of grasses, with an interspersion of legumes and other forbs...

s containing both cattle and sheep, one or two strands of barbed wire is used in conjunction with woven wire to both discourage cattle from reaching over the top of a fence and to keep sheep from crawling under. Though often used in many areas for 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, barbed wire is not advised; its use is considered poor management

Horse care

There are many aspects to horse care. Horses, ponies, mules, donkeys and other domesticated equids require attention from humans for optimal health and long life.-Living environment:...

. There is very high risk of injury occurring when a thin-skinned, fast-moving animal with long legs runs into it or puts a leg through the strands.

Smooth wire

Smooth (or plain) wire is essentially the same product as barbed wire with no barbs – either a two-wire twist or a single strand. Its primary advantage is that it is less likely to cause lacerations and cuts if an animal becomes entangled in it or rubs against it. However, animals will readily lean on mild steel smooth wire, stretching it out of shape or loosening it from the posts, and for this reason it is often used in high-tensile form, which more easily springs back to its original length. Smooth wire fencing is often used as an inexpensive material to safely contain horses and other animals that run a high risk of entanglement, usually in conjunction with a line of electric fence

Electric fence

An electric fence is a barrier that uses electric shocks to deter animals or people from crossing a boundary. The voltage of the shock may have effects ranging from uncomfortable, to painful or even lethal...

. Smooth wire is also used in securing fence-post braces and other uses where barbed wire is not recommended

High tensile wire

High tensile (H-T or HT) fencing is a special hard, springy steel wire was introduced in the 1980s and has slowly gained acceptance. The wire may be a single strand plain or barbed wire, or woven mesh, and is capable of much higher tension than mild steel. It permits the use of wider post spacings and is neither stretched easily by animals, nor by fallen trees or branches. It can be insulated and electrified. Because of the wide spacing of the posts, thin metal or wood spacers (or "droppers") may be attached to the wires between posts to maintain their spacing.

Joining HT wire is difficult because of its stiffness and its reduction in strength when bent sharply. However, it may be joined effectively with proprietary clips. HT wire is more expensive than mild steel, but because of the need for fewer posts, the overall cost of the fencing is usually comparable.

Because it does not stretch, animals are less likely to become entangled in HT wire. However, for the same reason, if an animal does become entangled or runs into a few strands at a high speed, it can be deadly, and is sometimes referred to as having a "cheese slicer" effect on the animal.

Trellising for horticultural purposes is generally constructed from HT wire as it is able to withstand a higher crop load without breaking or stretching.

Woven wire

Barbed wire cannot effectively contain pig

Pig

A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...

s, goat

Goat

The domestic goat is a subspecies of goat domesticated from the wild goat of southwest Asia and Eastern Europe. The goat is a member of the Bovidae family and is closely related to the sheep as both are in the goat-antelope subfamily Caprinae. There are over three hundred distinct breeds of...

s or sheep. Where these animals are to be fenced, woven wire (called sheep or pig netting in Britain, sheep fence or hog fence in the United States) is used instead, often with one or more strands of barbed wire at the top. For swine, a ground-level barbed wire strand or electrified wire is used as well to prevent them digging beneath the fence.

Agricultural woven wire is identifiable by wire "knots" wrapped around each intersecting wire. Cheaper forms of wire used in residential fences are often spot welded at junctions and as such are less sturdy and may break, creating a hazard for enclosed animals. Woven wire is more costly to purchase and time-consuming to install than is basic wire, but is often safer and less expensive than wood, pipe, or other materials.

Woven wire with large openings (known as "sheep fence" in the western United States and Ringlock in Australia) has some potential hazards. Animals contained inside the fence can easily put a foot through the wide squares while grazing along the edge of the fenceline or while reaching over it, and then become tangled in the fence. It is also dangerous for wild animals, such as deer

Deer

Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...

, kangaroo

Kangaroo

A kangaroo is a marsupial from the family Macropodidae . In common use the term is used to describe the largest species from this family, especially those of the genus Macropus, Red Kangaroo, Antilopine Kangaroo, Eastern Grey Kangaroo and Western Grey Kangaroo. Kangaroos are endemic to the country...

s or wallabies

Wallaby

A wallaby is any of about thirty species of macropod . It is an informal designation generally used for any macropod that is smaller than a kangaroo or wallaroo that has not been given some other name.-Overview:...

that attempt to jump such fences. These can become trapped when their back feet clip the fencing and get caught. While they can be cut out, they are often seriously injured and must be euthanized

Animal euthanasia

Animal euthanasia is the act of putting to death painlessly or allowing to die, as by withholding extreme medical measures, an animal suffering from an incurable, especially a painful, disease or condition. Euthanasia methods are designed to cause minimal pain and distress...

. A variation, called "field fence," has narrower openings at the bottom and wider openings at the top, which prevents animals from getting their feet entangled while grazing close to the fence, though is of little help if an animal becomes tangled in the openings higher up.

Horses and ponies in particular are safer kept inside woven wire fence with squares of smaller dimensions, such as "no climb" fence with squares that are approximately two inches by four inches. This type of wire is also more effective for containing goats.

Another variant on woven wire is the "hog panel," which consists of heavy welded wire approximately 0.25 inches (6 mm) or more in diameter. It resembles field fence in appearance, but is sold in panels rather than rolls and is not easily wrapped or bent. However, larger livestock such as horses or cattle can easily deform hog panels, so if used to contain large animals, it requires supporting rails or pipe on both the top and sides. It has some of the same strengths and weaknesses as field fence. Though animals are less likely to become entangled in it, the wire is far harder to cut if they do.

Chain link fencing is, arguably a form of woven wire, and is occasionally used for some livestock containment. However, due to cost, it is not particularly common for fencing large areas where less-expensive forms of woven wire are equally suitable. When used in small enclosures, it is easily deformed by livestock, resulting in high ongoing maintenance costs.

Deer fence

Deer

and many goat

Goat

s can easily jump an ordinary agricultural fence, and so special fencing is needed for farming goats or deer, or to keep wild deer out of farmland and gardens. Deer fence is often made of lightweight woven wire netting nearly 2 metres (about six feet) high on lightweight posts, otherwise made like an ordinary woven wire fence.

In areas where such a tall fence is unsuitable (for example, on mountains subject to very high winds), deer may be excluded (or contained) by a fence of ordinary height (about 1.5 metres, four feet), with a smaller one of about one metre (three feet) high, about one metre away from it, on the same side as the deer. The additional width prevents deer approaching the fence close enough to jump it.

Electric fence

Electric fencing became widely available in the 1950s and has been widely used both for temporary fences and as a means to improve the security of fences made of other materials. It is most commonly made using lightweight steel wire (usually 14-17 gauge) attached to posts with insulators made of porcelain

Porcelain

Porcelain is a ceramic material made by heating raw materials, generally including clay in the form of kaolin, in a kiln to temperatures between and...

or plastic

Plastic

A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...

. Synthetic web or rope with thin steel wires interwoven to carry the electrical charge has become popular in recent years, particularly where additional visibility is desired.

A fence charger places an electrical pulse from ground to the wire about once per second. The pulse is narrow and usually around 5-20 kV. Animals receive an uncomfortable but harmless shock when contacting the wire, and learn to stay away from it.

Synthetic fence

Synthetic fences encompass a wide range of products. Vinyl

Polyvinyl chloride

Polyvinyl chloride, commonly abbreviated PVC, is a thermoplastic polymer. It is a vinyl polymer constructed of repeating vinyl groups having one hydrogen replaced by chloride. Polyvinyl chloride is the third most widely produced plastic, after polyethylene and polypropylene. PVC is widely used in...

-coated wire fence is usually based on high-tensile wire with a vinyl coating. Some forms are non-electric, others embed layers of graphite

Graphite

The mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Ancient Greek γράφω , "to draw/write", for its use in pencils, where it is commonly called lead . Unlike diamond , graphite is an electrical conductor, a semimetal...

to carry a current from the wire to the outside of the coated product so that it can be electrified. It can be of any color, with white particularly common in the United States so that the fencing is visible to livestock. Most forms can be installed on either wood posts or steel t-posts.

A variant, sometimes called "vinyl rail" or "strap fencing" consists of two or more vinyl-encased wires with vinyl or other synthetic between them to create a "rail" that is anywhere from 1 to 10 cm (0.393700787401575 to 3.9 in) wide. Some forms may be electrified by use of a special coating on the top wire of the "rail."

Vinyl fence is installed in a manner similar to plain high-tensile fence and must be stretched tight. Strong bracing of posts at corners and in the middle of long fencelines is required. Like other wire fences, keeping vinyl fencing tightened on a regular basis is key to safety and appearance.

A mesh form of vinyl fencing without internal wires is marketed as "deer fence" and used in some locations to augment other fencing to keep out wild animals. There are also some forms of vinyl fencing that look similar to vinyl-coated wire, but do not contain an internal wire, that are marketed to livestock owners. They are marketed as particularly safe, but their strength in containing animals is under debate. These products are very new to the market.

Wood, pipe and other materials

Fences of wood, stranded cable, and pipe are used where cost is less of a consideration, particularly on horse farms, or in pens or corrals where livestock are likely to challenge the fence. Synthetic materials with wood-like qualities are also used, though they are the most expensive option in most situations. In some areas, these types of fencing materials can be cost-effective if plentiful. For example, scrap pipe is often easily obtained at a low price if oil fields are nearby, and wooden rails can sometimes be harvested from the owner's own land if it contains suitable standing timber.

Fladry line

Fladry line

A fladry line is essentially a line mounted along the top of a fence, from which are suspended strips of fabric or some other material which will flap in a breeze, and intended to deter wolves from traversing the fence-line. Fladry lines have been used for this purpose for several centuries. They...

s, made of cloth, metal and/or other materials, are sometimes used on fences to discourage predators from entering a livestock enclosure.

Maintenance

All types of agricultural fencing require regular maintenance to ensure their effectiveness. Cattle and horses are strong enough to go through most types of fence by main force, and occasionally do so when frightened or motivated by hunger, thirst, or sex drive. Weather, flood, fire, and damage from vandals or motor vehicle accidents can do similar damage and may allow livestock to escape.

External links

Fence Planning for Horses

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

History

Fence laws

Wire fences

Barbed wire

Smooth wire

High tensile wire

Woven wire

Deer fence

Electric fence

Synthetic fence

Wood, pipe and other materials

Maintenance

See also

External links