Whether you keep your horses at home or board them, forage is their primary diet and an aspect of horse management that you shouldn’t overlook. 

Given a choice, your horse would graze for 16 hours every day. But that enthusiastic grazing can quickly turn a lush, green pasture into an uneven, weedy mess without careful management. Whether your horse goes out for two hours, or for 24, a little maintenance and care can save you a lot of money down the road when it comes to growing healthy and nutritious pastures.

The first step to a healthy pasture is recognizing what it should look like.

“You want a pasture that has beneficial or desirable plants and no weeds,” said Shea Porr, Ph.D, and extension agent with the Virginia Cooperative Extension. “When you’re looking at the pasture, you don’t want to see lots of bare dirt spots. You don’t want the grass to be an inch or two off the ground. You don’t want to see a lot of weeds.”

But even if your pastures already look healthy and full, it does take some preventative care to keep them that way. Horses, by nature, are picky grazers.

“Horses will find areas that they like to graze. If you turn the same horses out in the same acreage time after time, they’re going to graze the same spots, which will eventually become bare spots and grow weeds,” said Porr.

Horses are also close grazers, which means they prefer to eat grass down to nubs. They choose a location to defecate too, so it doesn’t take long for a pasture to get uneven—grazed short in the places where the horses find the tastiest grass and long and weedy around the manure.

That’s why Porr and other grazing experts are so adamant that horse owners practice rotational grazing, even on properties where there’s far more forage than the horses can eat.

“Even if you have two horses on 10 acres—and that’s plenty of acreage for two horses—I would still recommend breaking that into two or three paddocks,” said Porr. “That way you can rotate from pasture to pasture, and it will allow the grass to rest.”

Rotational grazing can be as simple as switching between a paddock and a dry lot to give the grass a rest, or as complicated as moving animals every day to fresh grazing.

“As a rule of thumb, most grasses in pastures tend to be tall erect species, so you should pull them off when the grass is 3 to 4 inches tall and let them back in to graze when it’s 6 to 8 inches,” said Porr.

However, some grasses, like Bermudagrass, are lower growing plants and can be safely grazed down to 2 inches, so it’s important to know what species of forage grows in your fields.

Management-intensive grazing is a method of grazing that divides large fields into smaller paddocks. Animals are moved frequently at high stocking rates, the number of animals per acre. This system is more commonly used for cows, but the concept works for horses too. A large number of horses in a small area will graze more evenly, and their manure will be spread more evenly over the acreage to fertilize the grass. You move the horses into a new paddock before they graze the grass too short and start all over again.

“The horse people could learn something from the cattle people when it comes to rotational grazing and managing grazing,” said Porr. “I think rotational grazing is a key that horse people haven’t picked up on. It’s very valuable, not only for equine health, but also for pasture health. Horses don’t need to be moved every day, but if you had enough pasture to move them once a week, that probably would keep them from overgrazing and would still give the ground time to recover.”

Know Your Forage

The more you learn about rotational grazing, the more benefits appear. By rotating, you can create pastures with different species of forage to maximize the efficiency of your land.

Optimal growing temperature is one way to categorize forage. “Most of what we have are cool season grasses,” said Porr. “Orchardgrass, bluegrass and fescue are just a few of the common ones. Cool season forage grows during cooler temperatures. It starts growing earlier in the spring.

As it gets hot, it will stop growing and go dormant. Then come fall, it will start growing again, and it will grow further into late fall and early winter when it becomes too cold.”

Warm season forage grows during hot temperatures. Crabgrass and Bermudagrass are two warm season forages. “The forage specialist would like you to have one pasture that’s cool season and then another pasture that’s warm season,” said Porr. “They don’t compete that way, and you get better growth. If you can alternate fescue and crabgrass, you’d have grass for the majority of the year.”

Porr doesn’t recommend trying to mix too many species of forage in one field, however.

“The more species you have in a field, the more competition there is. There’s a greater chance that two of them might kill each other off as opposed to the two proliferating together,” she explained. “However, if you’re going to mix anything, I’d recommend putting a legume in there, probably a clover. They stand up better to wear and tear by horses. Anything from 15 to 30 percent clover in a field can help with your nitrogen fertilization because it fixes the nitrogen. It also raises the nutrition of the pasture overall. There’s more protein in a legume and there are more minerals. I don’t recommend having more than 20 to 30 percent of the legume in the pasture because that’s overkill for horses.”

You can also stockpile forage through rotational grazing.

“Do a mow in late August or early September and let it grow all through the fall,” suggested Porr. “When all the other pastures have been grazed down, then you can start turning out into that one in January or February. Treat it as though it were a hay-type forage. I’d recommend turning them out for a short period of time to extend the grazing. Just make sure they have access to hay or something to forage on when they’re in their sacrifice area or in their stalls.”

Another benefit of rotation is that it makes manure management easier. Horses tend to defecate in a certain area of the field, so that area will need to be dragged to spread the manure and break it apart.

“I think one has to look at manure as an organic fertilizer. It does have value,” said Keith Johnson, Ph.D. and forage specialist at Purdue University (Ind.). “That’s one of the things that management-intensive grazing allows to happen more effectively. When you’ve got smaller acreage and the water is properly placed, there will be more defecation and urination throughout that small acreage as compared to next to their favorite shade tree or waterhole.”

With rotational grazing you can drag a paddock, and even spread manure on it, when the horses are grazing in a different pasture.

“You don’t want to spread it unless the field is growing, because grasses don’t utilize nutrients when they aren’t growing,” said Porr. “Spreading it in the middle of summer on your cool season fescue does you no good. The first time it rains, it runs off.”

Spreading manure in fields where horses aren’t grazing is good for your parasite prevention program, as allowing the manure to dry out in the sun kills parasites.

Layout 101

Once you decide to rotate your pastures, you have to put some effort into planning the layout of your farm.

“I think a dry lot is a very important piece of the property,” said Porr. “A dry lot or sacrifice paddock is an area where you intend to keep the horses when you can’t turn them out on the pasture, because the pasture grass isn’t tall enough. Normally, those sacrifice areas have no grass in them, so you’re feeding them hay while they’re in there. It not only protects the pasture, but also it’s a place to put your horses that are overweight, insulin resistant or founder-prone in the spring.”

Porr recommended locating the dry lot near the barn. “If it’s not, it’s not going to get used,” she said. “It needs to have appropriate footing. It needs to be in an area that’s well drained. If it’s going to turn into a bog, then you need to look at having some stone dust or gravel brought in. It may cost you something, but in the long run it’s going to be healthier for the horses, and it’s going to be much easier for you to manage and clean.”

She also suggested cleaning manure out of the dry lot so it doesn’t disintegrate and create more mud when it rains.

Horses won’t travel a great distance from their water source, so if you have large paddocks, you may find that the horses aren’t using the entire field because the back part is too far from the water. If that’s the case, try locating a water source along the fence line of two paddocks further out in the field.

However, it’s not a good idea for the environment to use natural water sources such as streams and ponds for water.

“Decreasing soil erosion around water sources and decreasing the leaching of nutrients into the water supply [is an environmental issue],” said Porr. “It’s recommended that you have a buffer area of 25 to 30 feet from the stream in order to have vegetation that will filter any water runoff from manure that might be in the pasture.

I encourage people to keep manure piles away from open water sources, to keep vegetated areas around water sources and keep the horses away from them in order to help with the environmental issue.”

It Looks Like Dirt

Sometimes, despite the best intentions, pastures start to look more like a weedy dirt lot than a thick carpet of grass.

“The biggest mistake I see is too many horses on too small an acreage,” said Porr. “Usually that creates bare patches, lots of weeds and no grass. It will look green from a distance, but when you walk out there, what you’re looking at is not grass.”

So what do you do if your pasture is in need of some major renovation? Depending on your goals, pasture renovation can be a huge commitment or a small investment.

When researchers at the Virginia Tech Middleburg Agricultural Research and Extension Center decided to grow Max Q Tall Fescue in a field, it was a major undertaking.

“First we did a kill, and then we planted two cover crops,” said Porr. “The cover crops help you to manage anything that might regrow and might come back out. We used millet.”

Finally, they planted the Max Q after harvesting the second round of millet.

“Your renovation can be something as extreme as that, or it can be as easy as liming, fertilizing and overseeding,” said Porr. “Usually, once you’ve gotten your pastures to good quality, maintaining them is much easier.”

This is also the time where your dry lot may come in handy. “If you need to reseed, then you have to give it time to grow so the roots can establish. It might be six months before you can turn out in that situation,”said Porr.

But before you start any kind of renovation, it’s important to test your soil.

“I recommend doing a soil test every couple years for a standard horse farm. If you are taking hay off the fields, then I recommend doing it yearly,” said Porr.

The only sure way to know whether or not your soil lacks nutrients is to test it. Most local extension agencies can provide you with a soil testing kit and tell you where to send soil for testing.

Be sure to request the soil pH, the buffer pH, the phosphorus and potassium levels, the organic matter and the cation exchange capacity. Magnesium levels are another thing to check, as horses require this mineral, and some regions of the country lack it.

If your results come back lacking then it’s time to either add limestone (calcium carbonate) or fertilizer.

Liming fields reduces the acidity of the soil. “Preferably, limestone should be applied six to 12 months before seeding to ensure sufficient time to lower soil acidity [i.e. raise the pH],” said Johnson.

There’s no danger to the horses if they’re turned out in a freshly limed field though.

“If it’s just been spread on a field and it’s dry, it coats all the grass,” said Porr. “So then the horses aren’t happy or they come in all gray. It’s nice to put the lime down and let it rain and run down the blades of grass into the ground. It does take a long time for it to incorporate into the soil and have an effect on the pH.”

When it comes to fertilization, though, it’s best to leave it to the experts, unless you’re inclined to hit the books.

“You’ve got to do more than say it’s good or it’s bad,” said Johnson. “The right follow through is not just to apply fertilizer but the proper type of fertilizer to meet the nutrient needs. The horse owner may feel that he or she has done something positive [by adding a generic fertilizer], but the reality is he or she may have created excess or didn’t put on as much as really needed.”