Published March, 2015

Electric fence use in horse pastures varies greatly across breeds, disciplines, and geographic locations. But regardless of where you are located or what you do with your horses, electric fence can be a valuable tool for improving your pasture management.

The key to successful electric fence use is proper installation and maintenance. When used properly, temporary electric fence is a safe and economical way for managers to encourage horses to utilize more of the available pastures. This reduces the need for stored forages such as hay, increases the farm's profitability, and reduces the operation's environmental impacts on the surrounding areas.

Benefits to Pastures

Horses are known as spot-grazers. They return to the same areas to graze and will leave other areas of pastures untouched. Grasses are more succulent in a short, leafy stage compared to the more mature, taller grasses nearby. Horses might also prefer one area of a pasture because it is closer to the gate, water, shade, or horses in a neighboring pasture. Heavily grazed areas will begin to deteriorate over time; you'll see large patches of weeds or bare soil where healthy grasses were once plentiful. Weeds can greatly reduce pasture productivity and quality; bare soil is likely to wash out during wet periods and might take with it nutrients or pesticides that will end up in surface and ground water. Often you can control spot-grazing by strategically setting up a temporary electric fence.

Installing electric fence in large pastures allows horse owners or farm managers to subdivide the pasture in a low-cost, temporary way. Subdividing allows for rotational grazing. While rotational grazing is often thought to be very complicated, it can be as simple as rotating horses from one side of the fence back to the other. Allow horses to graze one section of the pasture until the average pasture height is about 3-4 inches and then rotate them to another section. Clip or mow the recently grazed pastures to 3 inches to even out patches of undergrazed grass with more heavily grazed areas. Return horses to this section after they have grazed down other areas to 3 inches or regrowth has reached 6-7 inches. Rotation timing depends on grass species present, pasture size, number of horses, and weather conditions, but it will often be around 21 days on cool-season pastures in the spring and 28-35 days during the summer months.

Dividing pastures into front and back (instead of side by side) can give managers the option to encourage horses to graze different sections of a pasture that they might not otherwise want to graze. Always check for toxic weeds or other situations that cause horses to avoid these areas before installing temporary electric fence.

You can also use temporary electric fence to keep horses out of certain areas of a pasture. If you want to apply herbicides to part of a pasture, for instance, fence off that area and allow horses to graze only in nontreated areas. Fencing can also keep horses away from wet areas, noxious weeds, or trees.

What Do You Need?

Keep in mind that temporary electric fence is first a psychological barrier and then a physical one. It is not recommended to use temporary electric fence as a perimeter fence for a pasture but rather as an interior fence to further subdivide the pasture. It is best to purchase all hardware from the same manufacturer, as individual parts of the fence will work better together.

Fence material includes polywire, polytape, and braided rope. Horse owners need to select a fence type that they are comfortable with and is easy to use and maintain. The wider 1 ¼-inch tape is more visible, but it tends to catch wind and water, resulting in stretching. The ¾-inch tape works well, is visible, and easy to use, as are the braided rope products. If you experience a lot of wind in your area, consider the rope rather than the tape products. How many strands of tape or ropes used will depend on the horses in the pasture and the horse owners’ preferences. One strand can be effective, but in some cases two strands are needed to keep horses where you want them.

Select posts designed to be used with the type of fence you have selected. Posts can be made of fiberglass, metal, or plastic. Metal (such as t-posts) are not recommended with horses. Plastic posts are light-weight and inexpensive; however, they might not last more than a season unless they are UV-stabilized (meaning the sun will not break down the plastic). UV-stabilized posts are often more expensive, but are usually worth the investment. Fiberglass or some of the composite posts last longer and can be driven in, providing a very stable fence. Wear gloves when handling fiberglass posts.

The charger is the fence's source of electric current. Chargers can plug into a power source, such as in the barn, or can be battery- or solar-operated. Solar chargers might run low after several days of cloudy skies or if the solar panel is otherwise not exposed to the sun. Many chargers will have a combination of power options for backup when needed. The charger's size and type will largely depend on the length and type of fence you plan to install and the availability of power to the area.

For electric fence to work properly, it must be a completed circuit, which will require ground rods. Use galvanized ground rods to reduce rust and corrosion. Ground rods connect to the charger via wire and are buried in the ground. The number and length of the ground rods needed will again depend on the length, type, and strength of the fence; however, a general rule is three 6-foot rods for dividing a medium-sized pasture. Ground rods do not have to be driven straight into the ground, but can be put in at an angle or even trenched and laid parallel to the soil surface. If trenching, make sure the rod will not be exposed by minor erosion, as this will decrease the fence's effectiveness.

Lightning protection is recommended for electric fence systems, especially more permanent ones. Lightning boxes provide a way for the system to discharge excess energy in the event of a lightning strike. Otherwise, this energy will move back to the charger and can result in charger damage or fire when housed in a structure.

Other necessary items include wire to connect the charger to the fence and to the ground rods. Be sure the wire is the same type as the fence tape to prevent compatibility issues. Gate handles make it easy to install a simple gate to allow people, animals, and equipment in and out of the area. Make sure the gate is wide enough to allow animals to pass throughout without getting uncomfortably close to the fence, as they might panic and rush through. Electric fence indicators are available to warn others that the fence is electrified, and some will flash when the fence in on to indicate an active current. Fence testers might also be useful for testing the fence's current after it is set up.

Using Electric Fence Safely

Proper installation and maintenance is essential for temporary electric fence to be effective and safe around horses. While a strand of tape is adequate for most adult horses, you might need multiple strands for young, aggressive, or naïve horses. It is important to electrify all strands, so consider your design and needs before you select a charger. Keep fences tight to reduce blowing in the wind and prevent entanglement. When horses are first introduced to electric fence, be sure to provide ample room. Once horses have a respect for the fence, you might be able to reduce the size of the area or increase the stocking rate.

Accidents often occur when fences are not “hot enough,” or do not carry enough of a charge to completely deter horses from testing a fence. This is why using an appropriate charger for the length and type of fence is essential. While the shock from an electric fence is quick and harmless, it should be strong enough that there is no question in the horse’s mind where the boundaries are.

Check fences regularly for sagging or damaged tape or decreased charge. Weeds or grasses that grow up and touch the fence will decrease its charge; therefore, you will need to mow or weed-eat around fences that are standing for the season. As horses become accustomed to the fence and appear to give it a wide birth, remember to keep the fence on and working at all times.

Krista Lea, MS, assistant coordinator of UK's Horse Pasture Evaluation Program, and Bob Coleman, PhD, PAS, UK extension horse specialist, associate professor, director of undergraduate studies in equine science and management, and associate director of UK Ag Equine Programs, provided this information.