- Sep 1, 2008
With the advent of low impedance fence chargers, electric fencing has become a practical, reliable solution for horse farms seeking both permanent and temporary solutions. Not only does it keep horses from escaping, it allows stables the flexibility to manage the boundaries of their pastures according to their specific needs.
There are a number of electric fencing solutions on the market; however, they all operate based on the same technology: the fence charger or energizer (those familiar with older systems might recall the term "fencer") converts electricity into strong, short electrical pulses that travel down the fence wire every second or so. The fence can be a braided rope or woven tape with conductive material incorporated into it. When a horse touches the fence, the electricity is transmitted through its body to the ground and back to the fence charger, completing the circuit. The result: an electric shock that poses no physical threat, but that is extremely memorable.
"It's a psychological barrier: the animal associates that electrical stimulation with the fence, and, therefore, does not cross it," says Ben Beale, MS, extension agent at the University of Maryland Cooperative Extension in Leonardtown, Md.
Those who grew up on or around farms might recall that the electric fencing systems of yesteryear weren't as effective. Bob Kingsbery, a livestock and fencing expert witness based in Frisco, Texas, recalls, "Old-fashioned fence chargers were low power in terms of the pulse they put out: the pulse was longer, there was a higher voltage, but lower amperage."
He notes it's the amperage that provides the "power" to modern fence chargers.
"They (old fences) weren't very effective; they wouldn't electrify much (length of) the fence, and any kind of weeds or grass that came into contact with the fence would short it out and make the entire fence ineffective."
Today's low impedance fence chargers are configured at a lower voltage--generally from 5,000 to 7,000 volts--and feature higher amperage and lower pulses. "The voltage goes farther (more fence can be charged), it's not as easily shorted out by weeds and grass, and it also shocks harder," Kingsbery says. "It's still safe and much more effective than it was originally."
Kingsbery recommends electric fencing for everything except corrals, where horses risk bumping into it during the normal course of movement. It can be employed as a stand-alone fence, or farms might opt to install it alongside a nonelectrified barrier, such as a board fence.
"For horses, I highly recommend using (electric as part of another type of fence) for the perimeter," Kingsbery said. "Anytime you border a public road, it's a great idea to have an electric fence alongside of whatever kind of fence you have."
How Good Is It?
An electric fence is only as good as its installation, and the best way to ensure that it operates properly is to follow the instructions. The ground system is the most important element in electric fencing, as that is what produces the shock when something comes into contact with the fence. Kingsbery recommends a minimum of three 6-foot galvanized ground rods spaced 10 feet apart, regardless of the length of the fence. Beale warns that metal posts or rods pose an impalement threat; safety caps should be used to prevent horses from becoming injured.
Ground systems are especially important in dry climates, or when an area is going through a drought, because the ground doesn't conduct electricity very well. "There is the concern that when we are going through periods of drought, electric fences don't work as well as they would normally because the conduction isn't there," Beale says. "A lot of times people will water near the fences (or the grounding rods), or they just don't use the electric fence."
Kingsbery cautions farms against being "penny-wise and pound-foolish" while purchasing a fence charger. There are many solar-powered chargers on the market; however, he argues that they aren't as powerful as traditional units. "When people go to the store, they see a plug-in fence charger for $80 and a solar-powered fence charger for $150, and they think if it's $150, it's twice as powerful," he says. "It's not, because you are paying for the solar power (energy system) and the battery, and you're not getting much of a fence charger."
Kingsbery recommends low impedance 110-volt plug-in fence chargers, which cost between $80 and $400.
The electricity costs for using the fence all the time are minimal. "These pulses are only three-thousandths of a second, every second," Kingsbery says. "If a typical fence charger were on a meter by itself, it probably wouldn't turn the meter."
Watch the Wire
Farms must ensure that their electric fencing is visible; a horse cannot easily see strands of wire. When using high-tensile, smooth wire that is suitable for permanent fencing, a strand of white polytape should be used along with it.
Kristen Wilson, regional horse extension specialist at the University of Maryland Cooperative Extension, advises, "If you are using braided wire or the tape, and you are not using it as more permanent fencing--such as the flexible fencing with electricity in it, or high-tensile with polymer coating--you really need to be careful that the horses can see it."
Kingsbery touts wide polytape permanent fencing for its practicality: "I like that a lot for horses: it looks good and it works, and it's easy to install. You don't need a lot of bracing and the things you do for high-tensile wire, and it's a lot less expensive than wood or rail fencing."
It also can be safer for horses, Wilson notes, because it has some give. "If a horse were to fall into it, it does have that give of so many inches, depending on what kind you use," she says. "If you have more permanent fencing, such as boards, the horses tend to get injured a lot easier."
One of the biggest advantages of braided or tape-based electric fencing systems is how convenient they are for pasture management. Many farms install permanent wood fencing around the perimeter of a large pasture, then use electric fencing to divide it into several fields. "Because it is easy to move--especially if you use the metal (or plastic) posts ... you can setup rotational grazing systems," Wilson illustrates. "You can also use it within the pasture to rope off areas that you don't want the horse to go into, such as lower level areas where a lot of water collects easily."
Wilson says this approach to subdividing pastures also winds up being cheaper than permanent fencing, and it is easier to install and maintain.
How Long Does It Last?
While there are quality differences between brands and models, today's electric fencing systems generally withstand the elements. "The polymer-coated high-tensile fences (some of which can be electrified) are very sturdy, and many companies offer 20- or 30-year warranties," Beale notes, adding that farms should be aware that the braided rope, depending on the quality, does have a tendency to degrade in the sunlight. "You want to make sure you have a good-quality conductor; a lot of the electric ropes will have stainless steel, which will last a lot longer. Normally, you can get five to 10 years of use out of nonpermanent braided rope or electric rope fence."
Polymer-coated wire electric fencing is similar in price when compared to traditional board fences. The cost of braided electric rope or tape varies; Beale estimates it at $30 per 600-foot roll. "Over the long run, it can actually be cheaper because the maintenance requirements for a board fence are high," he says.
Caution and Maintenance
Signs should be posted nearby alerting staff and boarders that the fence is electrified, although people that touch it will probably feel less of a shock than a horse would. "It actually shocks a horse harder because they are larger and they've got four feet on the ground with steel horseshoes," Kingsbery says. "They are well-grounded and, as a result, they get shocked harder."
While horse farms generally steer away from barbed wire fencing, Kingsbery underlines that if it is used for horses, it should never be electrified, as a horse getting caught up in an electrified barbed wire fence will likely injure himself more severely than if the fence weren't electrified.
Once installed, electric fencing should be checked regularly for shorts or failures. Kingsbery recommends that stable managers make monitoring the system with a voltmeter part of their daily routine. "Electric fencing is electric: if it's not on, it's not an electric fence," he says.
Thunderstorms and obstacles such as fallen branches also impede an electric fence's performance. "In order for an electric fence to work, it needs to have electric energy coming from somewhere," Beale says. "If there is a lightning storm, the power goes out, or a tree falls across the fence, or even a stick falls across the fence and shorts it out--and you don't recognize the problem for a few days--the horses will test it, and they can then get out. It's not something that you just put up and leave without checking it."
Electric fencing comes in a variety of styles and different price ranges, and horse owners are using it on farms to contain horses, reinforce boundary fences, and keep horses out of dangerous areas or sections they want to preserve with rotational grazing. While it isn't cheap, often it is less expensive than other forms of fencing. Electric fences are not maintenance-free and you must check them routinely to make sure they are working.
About the Author
Carolyn Heinze (carolynheinze.blogspot.com) is a freelance writer/editor. She currently works from her pied à terre in Paris, France, where she continually dreams of convincing the French Republican Guard to let her have a go-round on one of its magnificent horses. One can dream, can't they?
POLL: Groundwork Practice