Types of FencingSelect your type of fencing based on cost, type of livestock, maintenance, and durability. Horses will run through a fence or get tangled in it causing harm to themselves. Cattle and goats will crawl over fences, sheep try to crawl under. Hogs, of course, try to root their way under a fence. Alpacas and llamas will rub their beautiful fleece on barbed wire. Any livestock will put a fence to its greatest test when there is a lush green crop on the opposite side, or an opportunity to breed. Woven Wire Fences
Woven wire fences are available in numerous combinations of wire sizes and spacings, number of line wires, and heights. Most fences range in height from 26 to 48 inches. Stay wires should be spaced 6 inches apart for small animals and 12 inches apart for large animals. Woven wire fence that features a knot at the intersection of horizontal and vertical wires is the strongest type of woven wire--much stronger than welded wire. Barbed Wire Fences Suspension barbed wire fences consist of four to six strands of 12 1/2-gauge barbed wire stretched taut so no more than 3 inches of sag exists between posts. The wire strands are held apart by twisted wire stays or plastic battens or droppers spaced 16 feet apart. Line posts are usually spaced 80 to 120 feet apart. Cable Wire Fences A heavy-duty spring is fixed to one end of each cable and attached to an anchor post to absorb the shock on the wires caused by animal contact. The fence may consist of as many cables as desired, although a 6-cable fence is recommended for large animals. This fence has become less popular in recent years; 10-strand high tensile electric fence has taken its place. Mesh Wire FencesMesh wire is made in 11, 12 1/2, 14, and 16 gauges and fences are available in diamond-mesh and square knot designs. Fence height generally varies from 50 to 72 inches. The square knot wire design is formed from single line wires spaced 4 inches apart and stay wires spaced 2 inches apart (Figure 3). The joints are held by a piece of short wire formed into a knot. Board FencesBoard fences are made from 1- to 2-inch thick, 4- to 6-inch wide boards nailed to flat-sided wooden posts (see Fencing Materials and Equipment section). Board fences can be built to any height, although 4 1/2 and 5 foot heights are most common. Posts are typically spaced at 8 feet. However, board length should always be checked before deciding on spacing. For example, if 16 foot boards are purchased, the posts cannot be driven straight enough to attach the boards every 8 feet and post spacing must be decreased. Board fences are strong, attractive, and safe for animals. However, these fences are often built incorrectly by placing the boards on the wrong side of the post to maintain aesthetics. Boards should always be attached to the side of the post facing the livestock. Otherwise, animals tend to push boards off the post when they lean or push themselves against the fence. Board fences are expensive to build and maintain. Furthermore, the addition of one more board significantly increases the amount of materials needed or the labor required to build and maintain the fence. Labor is considerably higher for board fences than for most wire fences. Other disadvantages include splintering, breaking, and rotting of boards. High Tensile FencesHigh tensile fencing is easy to handle, requires little maintenance, and can be relatively low-cost. This type of fencing can withstand livestock contact and low temperature contraction without losing its elasticity. High tensile wire undergoes reduced stretch or sag, which is commonly associated with conventional fence wire. This type of fencing is not recommended for horses unless electrified versions are used and the owner is willing to accept some risk of injury. High tensile fencing is constructed with 11- to 14-gauge wire with a tensile strength of 170,000 to 200,000 pounds per square inch (psi) and breaking strengths of approximately 1,800 pounds. Wires are held in tension along posts spaced 16 to 90 feet apart. At installation, each wire is tightened with a permanent in-line strainer (Figures 5a and b) and is set at 200 to 250 pounds of tension. In-line strainers should be placed near the middle of the fence line to provide the same tension in both directions. Tension indicator springs are used to set and maintain the correct wire tension. Use one tensio n spring on one wire per fence and set it to the proper tension. The other wires can be tighten ed to the same tension by feel or sound (similar to tuning a guitar). The tension spring is general ly set on the second wire. However, placing the tension spring on the top wire provides some additional "give" to minimize damage caused by falling tree limbs. Electric FencesElectric fences are a safe and effective means of providing permanent and temporary fencing for most livestock. Their purpose is to supply sufficient electrical shock to any animal, whether livestock or predator, that comes in contact with the wire. Livestock that are unfamiliar with electric fences must be trained to respect and stay away from the electric wire.
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Woven wire fences consist of smooth horizontal (line) wires held apart by vertical (stay) wires.
Spacing between line wires may vary from 1 1/2 inches at the bottom for small animals to 9 inches
at the top for large animals. Wire spacing generally increases with fence height. 
Barbed wire consists of two or more strands of smooth, galvanized wire twisted together with two
or four sharp barbs spaced every 4 to 5 inches. Standard barbed wire fences usually have three
to five strands of barbed wire stretched between posts. Typical fence height is either 51 or 54 inches.
Spacing between wires depends on the number of line wires and fence height. Line posts are
usually spaced 12 to 20 feet apart. 
Cable wire fences are expensive and generally used for confinement areas. These fences consist
of 3/8-inch steel wire cables stretched between anchor posts. Fence height varies from 60 inches
for a 4-cable fence to 72 inches for a 6-cable fence.
