Developing a Grazing Management Plan for Horses
Crop and Soil Environmental News, March 1997
Paul R. Peterson,
Extension Agronomist, Forages
Pastures furnish horses with high-quality, nutritious feed at a relatively low cost and help to maintain healthy animals by furnishing exercise, sunshine, and fresh air. The horse is a natural grazing animal. If the horse owner practices good grazing management; mature, non-working horses and well-developed, older yearlings can be maintained on pasture with no grain supplementation during a typical pasture season. Well-managed pasture can provide many of the nutrients needed by growing horses and work horses, but some additional grain and hay feeding is generally needed for these horse classes.
Virginia has tremendous pasture potential due to the adaptation of a wide variety of forage species, favorable moisture and temperature, and a long growing season. However, proper grazing management is necessary to take advantage of pasture's potential.
Development of a grazing plan requires an understanding of the growth requirements of forage species that can provide good grazing for horses in Virginia. Cool-season grasses that can be used include Kentucky bluegrass, tall fescue, orchardgrass, and timothy. Kentucky bluegrass and tall fescue are sod-forming grasses that are the most forgiving of poor grazing management.
Abortions, foaling difficulties, and milk production problems can be encountered with pregnant mares grazing endophyte-infected tall fescue. Keep pregnant mares off of infected tall fescue during the last three months of pregnancy. For other classes of horses, there have been no reported health problems when grazing tall fescue.
Orchardgrass and timothy are high quality bunch grasses that require more careful management to be productive and persistent under horse grazing. While timothy can provide high quality forage, it is often not the best choice for pasture in Virginia because of poor summer growth due to a lack of heat and drought tolerance.
White (Ladino) clover, red clover, and alfalfa are the best legume options to mix with cool-season grasses in horse pastures. Alfalfa should only be used where soils are well-drained and the pH is at least 6.2. It is important to regulate grazing to maintain legumes in the stand. A balance of 40% legume and 60% desirable grass in the pasture sod is a goal to shoot for. Tall grass tends to crowd out clover. If the clover is thinning, keep the pasture grazed or clipped to reduce grass competition. This will improve the legume's chances of flourishing. While horses generally prefer grasses to legumes, they do graze some legume. Legumes will enrich their diet, improve summer pasture production, and provide fixed nitrogen to the pasture grasses.
Pasture production can be stabilized by having different forage species in various pastures, thus extending the grazing season. For example, in the Southern Piedmont and Eastern Virginia, having pasture planted to bermudagrass will ensure summer grazing and a strong sod to support horse traffic. Dwarf pearl millet is a summer annual that works well for providing summer horse pasture, too.
Sorghum, sudangrass, sorghum-sudan hybrids, and Johnsongrass should NOT be used for horse pasture. These warm-season annuals have been known to cause a condition called cystitis which is characterized by paralysis and urinary disorders. Foxtail millet is also not recommended because diuretic effects have been reported.
Having a pasture of tall fescue allows the potential for stockpiling (accumulating) fall growth for late fall and winter grazing. Winter annual grasses such as winter cereals are excellent species for providing late fall, late winter, and early spring grazing.
The amount of pasture acreage required per horse varies with size and age of the horse, pasture species, the amount of supplemental feed, and soil productivity. In order for pasture to be expected to provide the majority of a horse's diet, 2 acres of pastureland is generally needed for a mature horse. The most common pasture management problem among horse owners is overgrazing because of too many horses on too small an area of land.
Ideally, the total pasture acreage should be divided into 2-4 separate pastures (paddocks). This will allow the flexibility to rotate horses among pastures to allow for recovery of pasture plants and clipping as well.
While a minimum of 2 acres of pasture per horse is ideal, oftentimes land area is limited to the point where only an acre or less is available. If horses are allowed to access this entire area, it is nearly impossible to maintain a pasture sod with constant traffic. In such cases, dividing the area into at least two lots is a practical solution. One lot can be an exercise lot where pasture is sacrificed, and the other lot(s) used for grazing. Key to this is not allowing overgrazing in the pasture areas -- permit grazing on the pasture sod only when sufficient growth is present.
Do not allow horses to graze pasture down to less than 2". Since horses are spot grazers, the only practical way to follow this rule is to subdivide pasture area into subunits and rotate the horses through. A rule of thumb is to allow about 4 weeks of recovery time between grazings for any one pasture area. This will ensure a stronger, more productive sod and reduce weed encroachment.
Because of their spot grazing behavior, there will almost always be areas of pastures that are underutilized and overmature. These areas should be clipped. Two to three clippings per year may be necessary to help promote more uniform grazing and aid in controlling weeds.
Horses should be removed from pastures during very wet soil conditions, since horses can damage even well-established pasture sods when they run, stop, and turn sharply.
There are advantages to grazing different types of livestock on horse pastures. For example, beef or sheep can be stocked together with horses, or they can follow horses in the rotation of pastures. Since they are more random grazers than horses, beef or sheep help to make more efficient use of pasture by grazing more uniformly and thus maintaining more of the pasture in a high-quality, vegetative stage.
Well-managed pasture with grazing horses is a beautiful sight. There are a few key management moves that the horse owner can make to ensure good pasture condition. Foremost of these is dividing pasture area into a minimum of two and preferably more paddocks.
For more information on pasture management for horses, go to your local Extension office and pick up a copy of VCE Publication 418-008 entitled "Horse Pastures for Virginia."