Horse Pasture ManagementBy OKFR Staff

As spring weather arrives, horse owners are often eager to turn their horses out to graze and exercise—but is the pasture truly ready?

With proper management, pastures can serve as a high-quality forage source and a safe space for exercise. Effective management can even extend the forage production season, helping to reduce hay expenses. On the other hand, unmanaged pastures often develop weed problems, lack nutritional value, and can pose health risks for horses.

Here are five key steps to help improve and maintain horse pastures:

1. Soil Testing, Fertilizing, and Liming

Annual soil testing is ideal, but due to cost, testing every five years for grazing pastures and every three years for hay fields is a reasonable alternative. Grazing pastures tend to lose nutrients more slowly than hay fields because some nutrients are returned to the soil through horse waste, whereas nutrients in harvested hay are removed entirely.

For guidance on soil testing, fertilization, and liming, producers can refer to the Oklahoma Forage and Pasture Fertility Guide, available through Oklahoma Cooperative Extension and OSU’s Division of Agricultural Sciences and Natural Resources.

2. Over-Seeding and Renovating Bare Spots

Over-seeding helps replenish forage stands and prevent weed invasion. Use a high-quality pasture seed mix, limiting legume content to no more than 25 percent to avoid excessive salivation in horses.

3. Sacrifice Area

Creating a sacrifice area—a small, fenced section (approximately 300 square feet per horse)—gives overgrazed pastures time to recover during periods of heavy grazing or adverse weather. Horses kept in sacrifice areas should always have access to clean water, adequate hay, good drainage, and waste management.

4. Rotational Grazing

Horses are more selective grazers than cattle and will often overgraze their preferred plants, eventually killing them. This leads to spot grazing and pasture degradation. Rotational grazing allows plants time to regrow and helps reduce waste due to trampling.

Manure concentration in preferred areas also decreases grazing efficiency and nutrient distribution, making rotation an essential tool. Horses should be moved to a new pasture when forage is grazed down to 3–4 inches in height.

5. Weed Control

Chemical herbicides are commonly used to manage weeds, but identifying the specific weeds present is essential for selecting the right treatment. To prevent herbicide resistance, avoid long-term use of the same active ingredient and consider complementary methods such as mowing.

Maintaining healthy pasture also includes proper fertilization and rotational grazing, which both help minimize weed invasion.

Forage Selection and Toxic Plant Awareness

Selecting the right forage species depends on factors like land resources, management goals, and available capital. A mix of cool- and warm-season forages generally provides the most cost-effective year-round grazing.

Warm-season grasses, such as Bermuda grass, are commonly used for their high yield, good nutritional value, durability, and responsiveness to nitrogen fertilization. Alternatives include old world bluestem and crabgrass.

Alfalfa, a warm-season perennial legume, is widely used as hay in Oklahoma and can be grazed, though grazing may not always be economical.

Cool-season grasses such as wheat, rye, oats, barley, and ryegrass can be sod-seeded into dormant warm-season pastures to extend the grazing season. Combining ryegrass with small grains often allows grazing later into the spring. Cool-season clovers like red, white, and rose clover also thrive in Oklahoma and provide excellent nutrition.

However, it’s important to recognize and remove potentially toxic plants from horse pastures. These include bitterweed, black locust, cocklebur, horsetail, milkweed, ornamental yew, pigweed, snakeroot, St. John’s wort, wild parsley or carrot, and yarrow. Grasses in the Sorghum genus can contain prussic acid, which may cause severe health issues and even death. Clovers and small grains in humid conditions may also develop mold, which can be dangerous to horses.