Nutrition

Better Grazing: Steps to Saving Your Horse Pasture

Is your pasture in need of some TLC to make it a viable source of forage for your horses? Here is some advice on how to get the best from your grazing.

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By: Amy Harris |

Forage is the most important part of your horses’ diet. But how many of us actually know how to gauge the health of our pastures, or how to remedy deficiencies? If your horses have grazed the same pasture for years without any sort of analysis or rejuvenation efforts, read on!

Not all grass is created equal, and, in fact, not all pasture plants are grasses; legumes are sometimes interspersed with grass species. If it all looks the same to you, and your horse hasn’t submitted a review from his recent dining experience, the only way to know for sure which plants make up your pasture is to have it analyzed. You can call on your local agriculture unit or equine nutritionist for help – they can perform the analysis for you or offer advice on how to do it yourself. While you’ve got an expert on the line, ask them which plant seed mixtures would best suit your herd and locale – nutrient content varies, and if it looks like it’s time to re-seed anyway (more on that to follow), you might as well use the good stuff!

Weeds and barren patches of earth are far easier to identify than plant species. While most pastures will have some rough or unpalatable areas, how do you know whether there is still enough forage to sustain your living lawn mowers? One way is the “step point” or “boot toe” method, which can reveal overall vegetative coverage and plant type. What you do is make a mark on the toe of your boot and walk a zigzag pattern across your pasture. Every 10 steps, stop and look at the mark on your boot, and note whether you are standing on grass, legume, weed, soil or something else such as a rock. (Take photos and do some online research if you’re unsure what you’re looking at.) Depending on the size of your pasture, you should make 50-100 stops.

From there, you can calculate the percentage of vegetative coverage. Ideally, your pasture should have more than 70% coverage. Knowing the plant length (aka sward height) and species of plants in addition to the vegetative coverage percentage can help you calculate an even more accurate determination of available pasture.

Hold Your Horses

Typically, an average adult horse will consume about 2-2.5% of their body weight as dry matter pasture per day. Pasture is about 50% dry matter, and the rest is water, so that means a 500 kg horse would consume about 12.5 kg of dry matter per day, or about 25 kg of fresh pasture. Depending on your pasture’s yield and the type of plants it’s made up of, that translates into each horse needing between two and three acres of decent pasture to munch on. That’s something to keep in mind when you’re horse shopping – you don’t want to overstock your land and leave your horses without enough to eat.

If you’re tight on space, it’s particularly important to implement a rotational grazing strategy and make use of a sacrifice paddock in order to give your pasture an opportunity to regrow. Rotational grazing means having multiple paddocks – whether permanent or temporarily constructed with electric fencing – that you can use for turn out, providing each one a rest and regrowth period.

Before a horse steps hoof into a pasture, the plants should be about 6-8” tall. You can let your horses have at
it until the pasture ‘stand’ has been grazed down to 3-4”
in height, then it’s time to shuffle on over to the next buffet. This is a good time to practice some weed prevention by bringing an actual mower into the paddock when the plants – including the no good, icky kind – have grown back to 4-6”. Mowing them down then will remove the seed heads and reduce the spread of some noxious weeds (the ones that reproduce by seed, not those sneaky underground perennial types that grow impressive root systems).

In a perfect world – like those little online horse farms some of us covet – you would have at least four decent-sized pastures to rotate your herd through. If you don’t have such luck, a sacrifice paddock can be used to give your pastures time to regenerate. When your horses are being turned out in this grass-free zone, they will need to
be fed hay. Free-choice access is ideal, of course, but you can also ration it out, provided you make sure each horse is still getting their daily quota. And, since horses will usually spend 18 hours a day foraging for food, you’d better supply some form of entertainment for them if you’re vying for horse mom or dad of the year (and want to avoid fence eating, squabbles or ulcers). Access to fresh water and some form of shelter is a must.

If you want to be extra kind to your pastures, consider confining your horses to the sacrifice paddock during damp periods as well. Those hooves can do major damage when the soil is wet – and who needs the mud?! This kind of mud wrestling can have a lasting negative effect on your pasture, decimating immature plants and severely reducing growth for the rest of the year. Horses should only be turned out for brief periods after the snow melts; once the ground is firm and the pasture stand is about 6” high, their regularly scheduled grazing routine can resume.

Allowing your pasture to become overgrazed not only compromises the plants’ health, but it can be harmful to your horses’ health as well. When plants have been nibbled down below 3”, the leaf area is greatly diminished, making it difficult to photosynthesize sunshine into regrowth. Plus, it lowers the carbohydrate stores in the roots, further limiting regrowth and plant health. As a result, stressed grasses store more sugars as fructans, which can induce laminitis and other metabolic diseases in some horses.

Pasture Recovery

If you find you’re losing the war against weeds, and you have less than 50% vegetative coverage in your pasture, you should consider re-establishing it by killing everything off using a non-selective herbicide or by plowing under and re-seeding the entire thing. Be aware though that both treatments can render the pasture unusable for one to two years.

If your situation isn’t quite that dire – say you’re in the 50-70% vegetative coverage zone – you could consider bringing in reinforcements in the form of grass pasture herbicides. Do get expert advice before you head out with the big guns. You don’t want to accidentally eradicate good plants too, like legumes that are vulnerable to such chemicals. And you may need special permission or certification to use certain products. Plus, it’s super important to find out how long you should keep your horses off the pasture after treatment – the time period may vary depending on the product you use, but expect a minimum of a week.

Often, horse pastures are neglected due to a lack of proper equipment, or because paddocks are on the small size, with gates that are too narrow to accommodate the type of machinery that keep crops weed-free. You can buy or rent a small-boom 12 volt sprayer that is suitable for the job and can be used with an ATV or small tractor. You can also take care of some species of weeds using a backpack sprayer and the right product. Again, ask someone in the know!

Sometimes, the bottom line is your pasture is tired, its best days are behind it and it needs to be re-seeded. Your new agronomist friend (aka your local soil and crop management expert), can help you figure out how to test your soil, fertilize it, determine what species of plants are best for your situation, and get it ready for seeding. As noted earlier, it will typically be one to two years before the pasture is ready for your horses to graze on again.

Re-seeding can also be done on a smaller, less extensive, scale though, if you don’t plan to plow under and restart from scratch. Many people opt to over-seed their existing pasture to (fingers crossed) fill in the bare spots. This is best done in the fall, with a no-till drill (ideally) or using the ‘broadcasting’ method, where you first harrow the pasture, then walk about and toss seed onto the troubled areas, in particular, and harrow again. Another method is frost seeding, which works with clover species of legume plants. Seed is broadcast onto the pasture in the early spring, before the ground has thawed, and as the frost comes out of the earth, it opens up and allows the seed to become one with the pasture. The proceeding cool, wet conditions promote germination. In either case, you’ve got to give the plants time to establish themselves before you let the horses back on the pasture to graze. Experts will tell you the ideal rest period is six to eight months, and that if you can get away with it, taking a cutting of hay off the field first is ideal. This not always feasible, however.

It’s a lot to think about, so do your research and seek advice from knowledgeable folks (like the agronomist or equine nutritionist) to ensure your horses are eating at a five-star establishment. Pastures take careful management to maintain, and it behooves us to make sure our idyllic vision of our horses’ grazing is true to life, and they’re not actually out there struggling to get a decent mouthful!

~ with thanks to equine nutritionist Shannon Pratt-Phillips, Ph.D. for her expertise