Grazing fresh forage while out on pasture can provide excellent nutrition for horses. But environmental conditions and horse needs can make it challenging to maintain productive pastures.

Some pastures require very little management to support a low density of horses. However, for horse owners with limited turnout space or poor soil quality, good management practices are critical for preserving pasture health.

Regular maintenance can improve pasture productivity even when optimal growing conditions are not met. Grazing management strategies are also critical to prevent overgrazing that can damaging fields.

This article will review how to keep pastures healthy with routine maintenance and grazing management. We will also discuss factors that influence pasture health and suitability for horses.

Pasture Evaluation

Pasture evaluation is the first step in developing a pasture management program for your equine facility. Owners should evaluate their property’s forage species and soil to determine pasture productivity and nutritional value for horses.

Other aspects of pasture management depend on paddock size and the number of horses. Proper management is key to preserving pasture health when owners keep a high density of horses on small acreage.

Forage Species

When planning horse pastures, examine the types of plants currently growing on your property and determine which forages are most suitable for your region.

Some forage species are hardier than others and stand up better to overgrazing when space is limited. For example, warm-season grasses such as bermudagrass can withstand more heavy grazing than cool-season grasses like orchard grass. [1]

Horses also tend to overuse parts of pastures with preferred forage species. Cool-season grasses can have elevated sugar levels under certain growing conditions, leading to overconsumption. [2]

Submitting pastures samples for analysis will give you an idea of the nutritional quality of your forage so you can allocate pastures for grazing and balance your horses’ diets.

Soil Testing

Soil pH and nutrient levels vary significantly between farms. Optimizing soil conditions for the forage species in your pasture will increase productivity and nutritional value.

Soil testing can also help you determine if you need to add fertilizer or other treatments to your pastures. [3]

Horse owners can contact their local cooperative extension or conservation district office to learn how to test pasture soil. Some offices provide test kits for horse owners to collect samples to submit for soil analysis.

A soil analysis evaluates nitrogen, phosphorous, potassium and other nutrient levels. pH levels reported in the analysis measure soil acidity. Pasture health will suffer if the soil is too acidic or low in nutrients. [3]

Horse Density

High stocking rates can stress pastures and reduce productivity. Research suggests stocking density higher than one horse per two acres alters pasture composition and decreases soil nutrient concentrations. [4]

The stocking rate is especially important if owners rely on pastures to meet most of their horse’s nutritional requirements. If facilities do not have adequate acreage to support continuous grazing, horses will need supplemental hay and limited turnout time to prevent overgrazing. [4]

Large, healthy pastures with a low density of horses are ideal and require little management. But horse owners can still make the most of limited pasture space with strategic renovation and grazing practices.

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Pasture Restoration

Pastures sometimes require restoration or renovation to improve grazing. For example, soil test results may reveal conditions that prevent plants from thriving. Owners can restore soil conditions by using fertilizer and lime according to soil analysis recommendations.

Owners can renovate pastures by seeding the field with desired plants if overgrazing has altered pasture composition. Regular maintenance will preserve pasture quality after renovation or annual restoration.

Lime

Balancing soil pH is essential to support healthy forage growth. The pH scale measures how acidic an object is on a 1 – 14 scale. Soils with a pH of 7 are neutral, greater than seven is basic, and less than seven is acidic. [5]

Soils with a pH between 6 and 7 allow maximum nutrient utilization for grass forages. More acidic conditions can limit nutrient availability and inhibit plant growth.

In these cases, applying agricultural lime can help reduce acidity and increase soil pH. [6] Lime (or limestone) is a basic inorganic material containing calcium, which increases pH and improves nutrient availability in soil.

Owners can apply lime at any time of year, but liming pastures during rainy periods will help it break down faster in the soil. [6] Keep horses off limed pasture until after rain, as lime dust can cause respiratory issues when inhaled.

Fertilizer

Plants rely on nutrients from the soil to support growth and reproduction. If soil tests reveal nutrient deficiencies in your soil, you may need to add fertilizers to increase pasture productivity.

Nitrogen, phosphorus, and potassium are three essential nutrients found in soil. Nitrogen is especially critical for forage quality. Yellow or pale-green forage and poor growth are signs of nitrogen deficiency in the soil. [7]

However, excessive nitrogen can contribute to water quality issues. General guidelines recommend that equine facilities apply 50 pounds of nitrogen per acre of pasture at the beginning of the spring growing season. [3]

Subsequent nitrogen applications depend on forage growth and should not exceed 30 pounds per acre. Summer applications are appropriate when conditions support pasture growth, but most nitrogen should be applied during the spring and fall. [3]

Certain fertilizers can also correct potassium and phosphorus deficiencies. Phosphorus improves plant root development, which enhances nutrient absorption from the soil. Potassium supports the plant’s ability to survive stressful conditions such as drought or cold. [8]

Seeding

Some pastures require seeding to introduce new forage species or increase stand density. Proper soil preparation with lime and fertilizer before seeding will support new growth.

Spring and late summer are the best seasons for reseeding. However, seedlings can face higher weed competition in the spring and struggle to survive dry, hot conditions in the summer before they are fully established. [17]

If soil pH is too low, apply lime at least six months before seeding to allow adequate time for pasture pH improvement. [6]

Seeding depth significantly impacts successful pasture renovation; planting seeds too deep often leads to forage seeding failure. But seeds also need enough soil contact to promote germination. A planting depth of ¼ inch ensures optimal growing conditions. [17]

Owners should mow existing vegetation or allow horses to graze the pasture as short as possible before seeding to suppress competition. Seedbed preparation also includes killing weeds and loosening compact layers of soil. [17]

Depending on available equipment, barn managers can use a hand spreader, push spreader, or drop seed spreader to spread seeds. Lightly harrowing after seeding will help cover the seeds.

Wait until renovated pastures reach at least 6 inches in height before reintroducing horses. After reintroduction, proper pasture maintenance and grazing management will protect the new forage and minimize the need for future renovation.

Pasture Maintenance

Pastures require ongoing yearly maintenance to support forage growth and optimal equine nutrition. Managers can continue improving pasture health after restoration with regular mowing, weed control, and rest periods.

Mowing

Mowing maintains a uniform pasture and limits weed growth. Reducing pasture height also promotes tillering – the production of side shoots by grasses. Tillering allows grasses to produce multiple stems from a single seedling and generate leafy, dense pastures. [9]

However, avoid over-mowing as this can limit the grass plant’s ability to regrow. Grasses store energy reserves at the bottom of the stem. Keep grasses at least 3 inches tall to preserve energy reserves and promote growth. [10]

Weed Control

Weeds compete with desirable forage species for nutrients, space, water, and sunlight. Some weed species are also toxic to horses. While most weeds cannot outcompete healthy pasture grasses, they can quickly take over poorly managed horse pastures. [11]

Regular mowing limits the growth of weeds by removing tall weed species and reducing seed production. [9]

Barn managers can effectively address weeds with herbicides before establishing new pastures. In established fields, maintaining a healthy stand of forage is the most effective weed management technique. [9]

Herbicide applications in established pastures is warranted when weeds become an ongoing issue, but herbicides are not a permanent solution. Facility owners must directly address the conditions that allow weeds to proliferate, which often involves pasture restoration and reseeding. [11]

The most effective herbicide and the best time to apply treatment will vary depending on the type of weeds in your pasture. Consult your local extension agent for herbicide recommendations and weed identification.

Most pasture herbicides don’t have grazing restrictions, but horse owners should pay close attention to label instructions to avoid adverse effects on pasture and animal health.

Walking Pastures

Regularly walk horse pastures so you can identify changes in vegetation early. Horse owners should monitor weed species and concentrations in their fields as a sign of pasture health.

Identifying and removing poisonous plants is critical for protecting horse health. Other hazards to check for while walking horse pastures include downed tree limbs, broken fencing, and holes or burrows into which horses could step. [12]

If bare spots are visible in the pasture, horses may be overgrazing in certain areas. These pastures need rest to recover before permanent vegetation damage occurs.

Resting Pastures

Prolonged use by horses can damage pastures. Heavy horse traffic compacts the soil; hooves can shear off and trample vegetation when horses run. Horses also tend to graze repeatedly on the most palatable plants. [13]

Overgrazing allows horses to remove plants at ground level and damage the parts of the grass necessary for regrowth. A high stocking density can increase the risk of permanently damaging pastures. [4]

Resting pastures allows grasses to restore energy reserves and regrow after intense use. Fields require rest when horses graze the grass to 3 to 4 inches. The best schedule for resting pastures will depend on your grazing management strategy and stocking density.

Grazing Management

Grazing management is a critical aspect of pasture health. Effective grazing practices minimize pasture damage while maximizing the nutritional yield from limited pasture space.

Rotational grazing and sacrifice areas are often necessary to preserve pasture health if horse owners don’t have enough space for continuous grazing.

Continuous Grazing

Continuous grazing is the simplest pasture management option for horse owners. Horses are turned out continuously in a single area throughout the year.

Continuous use often leads to horses eating down their favourite parts of the pasture while allowing other plants to overgrow. Overgrazing removes the leaf area the grass plant needs to capture sunlight for energy production. [14]

Palatable forages die because they cannot photosynthesize to survive and reproduce. Eventually, rough areas of weeds and less palatable forage will outcompete overgrazed forage species with more nutritional value.

Rotational Grazing

Barn managers can avoid overgrazing by implementing a rotational grazing system. Rotational grazing involves regularly moving horses between several paddocks to alternate pastures between use and rest periods.

Paddocks need to rest for several weeks for adequate recovery. Generally, owners should remove horses from the pasture when the grass is less than 4 inches and allow grazing again when it grows to 8 inches.

Rotation time will vary depending on climate, season, pasture size, and stocking rate. Additional pastures will improve pasture health by lengthening the rest period. The higher the stocking rate, the more rest pastures need to recover from grazing. [15]

Studies show that rotational grazing increases pasture productivity compared to continuous grazing. Research also shows that periods of overgrazing can influence forage regrowth even after prolonged rest. [15]

Sacrifice Areas

Horse owners might need to use sacrifice areas, also called dry lots, when rotational grazing alone doesn’t provide enough time for pastures to recover.

Controlled grazing is often necessary during periods of reduced pasture growth. Some horses also need restricted grazing due to metabolic conditions, which increase the risk of pasture laminitis. [16]

Sacrifice areas help protect vegetation by removing horses from pasture during periods of new growth or in adverse conditions that make the ground susceptible to damage from heavy use.

Summary

  • Horse pastures require grazing management to maximize pasture productivity and forage nutritional value.
  • Evaluating pasture health involves identifying forage species, soil conditions, and horse density requirements.
  • Pasture restoration through liming, fertilizing, and seeding can improve soil conditions and pasture quality.
  • Routine pasture maintenance involves regular mowing, weed control, monitoring, and adequate rest periods.
  • Rotational grazing and sacrifice areas can help horse owners prevent overgrazing from damaging small acreage pastures.

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References

  1. DeBoer, M. et al. Yield, Nutritive Value, and Preference of Annual Warm-Season Grasses Grazed by Horses. Agron J. 2017.
  2. Zhao, D. et al. Interspecies Variation of Forage Nutritive Value and Nonstructural Carbohydrates in Perennial Cool-Season Grasses. Agron J. 2008.
  3. Voroney, P. Soils for Horse Pasture Management. Horse Pasture Manag. 2019.
  4. Singer, J. et al. Equine stocking density effect on soil chemical properties, botanical composition, and species density. Comm Soil Sci Plant Anal. 2001.
  5. Neina, D. The Role of Soil pH in Plant Nutrition and Soil Remediation. Appl Environ Soil Sci. 2019.
  6. Esperanza, A. et al. Limestone Particle Size and Liming Scheduling Influence Soil Properties and Pasture Production. Soil Sci. 2010.
  7. Aydin, I. et al. Nitrogen and phosphorus fertilization of rangelands affects yield, forage quality and botanical composition. Eur J Agron. 2005.
  8. Divito, G. et al. How do phosphorus, potassium and sulphur affect plant growth and biological nitrogen fixation in crop and pasture legumes? A meta-analysis. Field Crops Res. 2014.
  9. Hamilton, S. et al. Stubble Height Management Changes the Productivity of Perennial Ryegrass and Tall Fescue Pastures. Agron J. 2013.
  10. Jones, G. et al. Physiological Effect of Cutting Height and High Temperature on Regrowth Vigor in Orchardgrass. Front Plant Sci. 2017.
  11. Ghanizadeh, H. et al. Weed Management in New Zealand Pastures. Agronomy. 2019.
  12. Barr, C. et al. Toxic Plants: What the Horse Practitioner Needs to Know. Vet Clin North Am: Equine Pract. 2001.
  13. McCann, J. et al. Equine grazing preferences among winter annual grasses and clovers adapted to the southeastern united states. J Equine Vet Sci. 1991.
  14. Matches, A. Plant Response to Grazing: A Review. J Prod Agric. 1992.
  15. Weinert, J. et al. Recovery of Pasture Forage Production Following Winter Rest in Continuous and Rotational Horse Grazing Systems. J Equine Vet Sci. 2018.
  16. Watts, K. Pasture Management to Minimize the Risk of Equine Laminitis. Vet Clin North Am Equine Pract. 2010.
  17. Samson, J. et al. Sod-Seeding Perennial Grasses into Eastern Nebraska Pastures. Agron J. 1982.