Horse Hooves Stimulate Desirable Vegetation
Our Real-World Experiments
More and more people are buying into the West, acquiring quaint little "ranchettes", without realizing the responsibility they have to manage the "back twenty". Some of these hobby ranches have a horse or two for recreation, but the animals are often kept in the same pasture way too long, badly overgrazing the range until only weeds will grow. Most of the rest of these ranchettes have no livestock at all to trample the soils, so the land slowly becomes sterile and infested by weeds as the perennial grasses are no longer able to re-establish themselves. Our rangeland ecology work has been on finding ways to restore and maintain the health of these smaller parcels.
With a $2,100 educational grant administered by the Alternative Energy Resources Organization, we started out working with sheep and goats. These animals are known to favor eating weeds, while horses and cows tend to prefer grasses. Grant funds covered the capital costs of buying, building, and moving fences for the projects. The cost of the animals and feed was covered by participants in the project.
We discovered that it is true, sheep and goats do eat a lot of weeds, but it is also highly impractical to maintain a flock of weed eaters in a small town like ours. There is no economic reason to do so, since the meat, wool, and hides are all nearly worthless, unless you get into specialty wools and make a full-time career out of it. They also require a large amount of expensive fencing infrastructure and other maintenance. In an area where dogs are allowed to roam freely, predation is another problem. But we also discovered that sheep and goats were completely unnecessary, since we could get the same benefits and more by working with horses.
Horses are much easier to manage because they can be contained by a single electric wire around a pasture. Of course, they still require a huge investment of time and money to manage them, but at least there is the recreational benefit of riding them to make it all worthwhile.
So far we have developed six techniques to use horses to improve the land, including: 1) revegetating disturbed soils, 2) restoring dormant pastures, 3) green pasture stimulation, 4) summer pasture rotation, 5) trampling weeds, and 6) assisted lawn care. We will examine each topic individually in the following sections, then consider the appropriate use of herbicides to assist in pasture management.
Reclamation Work: trampling seeds and hay into disturbed soils. The soil in our neighborhood consists of mostly sand from decomposing granite. On the south-facing slopes the soil is thin and very exposed to the drying sun and wind. The sandy soil holds very little moisture, so it dries up quickly even after a drenching rain. Under these conditions, revegetation of disturbed sites can be a serious challenge, but we have learned that horses can be an effective tool for that purpose.
In a little town like this there are always many disturbed sites in need of revegetation. The easiest sites to reclaim are those that have been bulldozed, but still have viable soil. We broadcast new grass seed on the ground and put out hay for the horses. The horses eat what they can and scatter the rest, trampling hay and seeds into the ground. It is typically much less work and far more effective to revegetate disturbed sites this way, than to manually rake seeds into the soil.
This reclamation technique works any time of year, but it is most effective when the ground is moist (usually spring), so that the weight of the animals mixes the seeds and organic matter with the soil. This is a good way to use up older hay, especially when there is fresh green grass available in the same pasture The horses explore they hay and trample it in, but do not consume much of it.
We have also had good success reclaiming seriously disturbed sites with soft ground, but no real soil. One such site was the recontoured side of our driveway where the decomposing granite was exposed two feet below the original grade. We broadcast grass seed on the ground and fed the horses there through part of a winter, putting hay out in a different spot each day, until the entire site was worked over. The weight of the animals really mixed the seeds and organic matter into the soil, at least when the ground was thawed. For a site with no soil, we were extremely pleased with the results we got in the first season. Continued feeding on the site in subsequent years has further helped to revegetate the ground.
On another site my brother built his house into the side of a south-facing slope and backfilled around it. There wasn't much soil to begin with, and afterwards it was just loose, sandy fill dirt. To reclaim his yard we first broadcast the grass seed then started feeding hay. To speed up the process, he spread a thick layer of straw over the site for additional organic matter. We started reclamation late in the spring, but that worked out okay. The annual grasses that sprouted up first were protected in the straw mulch. The horses didn't seem to notice the tender young grass at all. Meanwhile, the heavy weight of the animals helped to mix seeds and organic matter several inches down into the ground. After three years of drought we didn't have enough moisture in the soil for the process, but he set up a sprinkler and saturated the ground and the straw, so that the horses really sank into the ground as they walked. The grass grew up so fast that he had to bring the horses back later to graze it all off.
We have also used sheep for reclamation work, but the greater weight of the horses seems to be much more effective at mixing seeds and organic matter into the soil. Even when the ground is completely frozen and the animals are just trampling the surface, the plots worked by horses seem to revegetate much better than those worked by sheep.
Dormant Pasture Restoration: building up the health of the soil. Overgrazing is a concern whenever a pasture is green and growing, so you cannot keep livestock in one place too long. But here in the arid west the forage plants stop growing when the moisture runs out. The vegetation above ground dries out while the roots go dormant in the soil to wait for new moisture, and the pasture typically remains dormant through the end of the summer season and all the way through winter. That means a pasture may be dormant for six to nine months of the year, depending on how long the moisture lasts through summer. And as long as the vegetation is dormant then it is impossible to overgraze it, except by completely eroding the soil away from the grass roots. In other words, you may be able to safely leave stock in the same pasture for more than half the year to fertilize and trample the soil without harming the plants at all.
If you own a few horses and have limited forage available, then you are probably buying hay all winter and through most of the summer already. You know why people call horses "hay-burners", but you don't have to throw all that money away for nothing. You can seize the opportunity to build up the health of the soil with every bale of hay.
People usually throw the hay over the fence in the same spot every day. It might seem easy and convenient to do so, but then the horses stand in the same spot every day and crap in the same spot every day, until there is a visible manure pile at the feeding spot. By spring time the pasture is completely smothered in that one spot, killing out all the desirable vegetation, so that only weeds can grow there. The solution is as simple as feeding the animals in a different spot every day.
Think about it every time you put out the hay-where is it needed most? Feed the animals where the ground is exposed and barren to trample organic matter into the soil. Throw hay out where there is standing dead vegetation or weeds that the horses don't want to eat. They will eat the hay and trample the vegetation into the ground. Put the hay out in a different spot just about every day, being careful to avoid getting so much manure build up in one spot that it will smother the existing grass and forbs when they emerge during the growing season. Rotating the water trough and salt block around the pasture will also help to focus impact where needed.
Just imagine, if your pasture grows only enough forage to feed your livestock for a month, but you keep feeding them there for several more months, you are increasing the organic matter in the soil by several fold and greatly accelerating the process of restoration.
This technique of feeding in a different place every day is most effective on those warmer winter days when the snow melts and the horses trample the organic matter into the muddy ground, but it is still highly beneficial at other times when the ground is frozen solid or even dusty dry.
On our pastures we have also accepted many loads of manure from other people's corrals, plus old hay and straw or tree leaves for mulch. All are raked out thinly in the pastures to build up the organic content without smothering the plants. Ashes from the fireplace are also scattered in the pastures for added nutrients. It is exciting to see the soil become darker and richer with each passing year.
We normally rotate our horses through the vacant lots of town all summer, then bring them home for the winter so it is easier to keep them watered. After months of trampling the same pasture, it looks almost like a feedlot on the side of the hill. The neighbors must think we are horribly abusing the land and trampling it into oblivion. But the truth is that it is difficult to overgraze a pasture when everything is dormant, and we seldom have a hoof on this place during the growing season.
Green Pasture Stimulation: working soils in springtime. Managing pastures in springtime is a much trickier process, since it is very easy to overgraze the grasses. When the grass is grazed off to the ground then it must steal energy from the roots to rebuild the green leaf surfaces for harvesting sunlight. Overgrazing occurs when the grass is eaten off again while it is still in this process of rebuilding itself. It has to steal yet more energy from its roots, ultimately stunting the plant or completely killing it when it is overgrazed enough times. Since the grass rebounds more quickly in the springtime when moisture is abundant, it is paradoxically more susceptible to overgrazing than it is when growth is slower. This means that ideally you may want to move your livestock as often as every ten days to avoid overgrazing your pastures. Any pasture that is too big to be completely grazed off in ten days can be divided into smaller plots with portable electric fences.
As you might sense, managing livestock in springtime is largely a matter of damage control to avoid over-grazing the land. Surprisingly, there are some situations where it can be desirable to overgraze the pasture a little bit, which I will return to shortly. First, it is helpful to understand how you can get some real benefit from the livestock while they are on a spring pasture.
To begin with, the animals will be motivated to eat any green growth in the very early spring, including the green growth partly hidden by old dead growth. In the process they bite off the old growth at the base, effectively chopping it down where it can decompose on the soil surface. Cutting down the old growth this way helps to more effectively recycle the nutrients back into the soil and puts more organic matter on the ground to trap in valuable moisture. Unfortunately, livestock completely avoid the dead grass when green growth is available by itself, so the technique only works through a short window of time.
Another benefit of springtime pasture work is that it is really easy to thoroughly trample the soil when it is soft and mushy after a recent rain or snow. The horses sink into the ground with every step, mixing organic matter and seeds with the soil. With only a few animals you get the same trampling effect as if you had a much larger herd.
On the other hand, there is a danger of over-trampling the soil under these conditions until it is packed down hard like concrete. The problem usually occurs where the horses stand in the same spot each day by the fence. Portable electric fences are helpful so that in a couple minutes work you can adjust the fence line over twenty or thirty feet to give the horses a fresh place to stand.
One vacant lot nearby was unfenced and hadn't been grazed in many, many years. The old grass was pushed down to the ground each winter by the snow, so it looked like it had a healthy covering of mulch, yet the grass there always had a greenish-yellow, splotchy color. We got permission to include the lot in our grazing program. Working the plot just one time in the spring left a peppering of horse manure all over the field. The grass grew back with wider leaf blades and a richer, darker shade of green. Bare sections of ground visibly filled in with new grass.
While you usually want to avoid overgrazing a plot, it is sometimes beneficial to do so, if it enables more effective trampling and fertilizing of the site. More trampling means more seeds and organic matter go into the ground to help new seedlings get started. The pasture may require additional rest to allow the stunted plants to recover from overgrazing, but there is a net benefit from any new seedlings that help to cover up bare ground. If the stock has eaten the pasture down to the ground and you are not quite ready to move them, then you can always feed hay for a few days to get the extra trampling benefit. Just keep in mind that at some point you will be doing more harm than good, and you really do need to keep the animals moving throughout the spring.
Even without overgrazing, any pasture that has been used in the spring may need to be rested the following spring to allow the grasses to fully recover, especially during drought conditions. You can still use the pasture during the dormant season, but try to give it full rest during the growing season(s) until the grass regains its vigor.
We like to work the vacant lots around town during the growing season. We ask permission from the owners then use electric fences to contain the horses. There always seems to be a neighbor willing to lend a faucet we can use to fill the water trough. We try to keep the horses on each plot as long as possible without overgrazing it, to effectively trample seeds and organic matter into the soil. Sometimes we broadcast seed on bare ground and feed a few bales of hay there after the rest of the pasture has been grazed off.
The greatest challenge is often to keep the horses in place long enough to finish the job, yet to move them out before getting complaints that we are overgrazing the land. On the other hand, the nicest thing about working pastures in spring is that the fast-growing grasses quickly shoot up from the ground, creating a vibrant green pasture shortly after we leave it. That helps to generate a positive image of the process.
Summer Pasture Rotation: As the ground dries out and hardens through the summer, but the grass remains green, there is less to be gained from trampling the soil. You can still get some positive impact immediately around water sources, salt blocks, or molasses treats, but it is difficult to get the same intensity of impact across an entire pasture--unless you fence in many very small plots. Therefore, livestock management is mostly a matter of damage control, keeping the animals on the move before a pasture is overgrazed. Fortunately, as the growth rate slows down it is possible to leave your stock in the same place for longer periods of time--often up to a month--without risk of overgrazing. Try to save your best pastures and those close to home for fall and winter, to minimize the amount of hay you will need to purchase later on.
Be sure to ask if you can use any ungrazed plots in your neighborhood. Putting those pastures to use helps prevent wild fires and converts organic matter into fertilizer and ground cover. It may not be as good as trampling in the spring or building up the soil with hay in winter, but it is better than nothing.
Always be sure to split the pastures if there is a danger of severely over-grazing the grass before the entire plot is eaten down. Put the water trough and salt block where the impact is needed most. And remember, you are dealing with someone else's property, so take darn good care of it!
Trampling Weeds: control by the hoof print. When a few horses are scattered over a large pasture for a long period of time, they will eat the same tender green grasses again and again while ignoring the weeds. The grasses suffer from the overgrazing while the undisturbed weeds are allowed to flourish and spread. That's why sheep and goats are so often used in weed control programs, since they prefer the weeds anyway. Over a period of years these animals eat away at the weeds, giving the competitive edge back to the grasses. But as we discovered, it is often impractical to raise sheep and goats for the sole purpose of weed control. Fortunately, you don't have too. Horses can effectively control weeds by simply trampling them into the soil.
A simple method is to move the animals into an appropriately small pasture and leave them there until they have grazed off all of the grass. Then keep them there a bit longer, but feed them hay (and water and salt) right in the weed patch. They will quickly trample the weeds right into the ground. The weeds might come back up from the roots, but they won't have the same vigor. Much like grazing the weeds with sheep and goats, this technique will not kill off the invading plants the first time through, but repeated over a period of years it will give the competitive edge to the grasses. To have the greatest impact, the technique should be applied each year just as the weeds are coming into bloom.
Although I am no fan of herbicides, let me emphasize that in most cases it is simply less hassle to spray a well-contained patch of weeds than to control them by trampling. In one experimental plot we started out working with sheep and $300 worth of portable electric net fencing. Then we upgraded to an elaborate $1,000 permanent sheep fence, since the pasture would double as a winter pasture the wooly weed-eaters. Then we decided sheep were too much trouble, so we started trampling the weed patch with horses. They do a good job, but it takes some effort to carry the hay into the middle of the weed patch. Besides, in a society with a lot of distractions it would be really easy to neglect getting around to a job like that.
For less than $50 worth of chemicals we could go in and spray this weed patch and be done with it. Sometimes our neighbors don't understand why we won't spray this patch when we are spraying other weeds around town, but the simple fact is, I've got too much invested in the weed patch to kill it now! I need to fully document the trampling technique before we finish off whatever is left with the aid of chemicals. I persist in my research simply because there are certain times and places that require alternatives to herbicides.
Assisted Lawn Care: have horses, will graze and trample. Mowing a lawn every week or two is a lot like overgrazing a pasture. The grasses sacrifice root energy to rebuild leafy green surfaces, making plants that are smaller both above ground and below. That's okay in a perennially moist environment because there is always enough moisture for new seedlings to establish and fill the bare spots. But here in the arid West, the only way to keep a lawn that moist is often by pumping water up from ancient aquifers that will never replenish themselves, or by stealing water from rivers that would otherwise support fish. Therefore, responsible lawn care is not about keeping a lawn lush and green all summer, but in allowing it to brown and become dormant like a pasture as moisture is lost from the soil.
While brown lawns are common in the West, they are usually plagued by the same problems as rangelands. Overgrazing (mowing) stunts the grasses, revealing bare ground, and there aren't any wild herds of bison running through the neighborhood to trample seeds and organic matter into the soil. Thus it is difficult to establish new seedlings to colonize bare ground, and many western lawns are characterized more by mowed dust and weeds than grass.
Our explorations into lawn care have been haphazard so far. I always intend to mow our lawn prim and proper, but cannot stand to waste either the gas or time for such a trivial purpose. Out of sheer necessity I have historically mowed the lawn an average of three times a year, and questioned the appropriateness of my actions every time.
When we acquired horses we also acquired less time to monkey around with meaningless tasks like pushing the lawn mower back and forth. The obvious new step was to periodically rotate the horses through the yard with the aid of portable electric fencing to keep them out of the bushes and flowers. That's one way to get the grass mowed, but it is a bit of work to set up the fence, and too much trouble to set up the charger. The horses would soon discover that the fence was turned off and subsequently walk right through it to graze the patches we hoped to protect.
With time, experience, and increased laziness, we discovered that the most effective way to mow the yard was to simply let the horses graze freely until they were full. They remain focused on the lawn as long as they are hungry. It is only once they are satisfied that they start sampling the bushes, trees and flowers. Mowing the lawn is simply a matter of keeping an eye out the window until the horses start exploring. Then it is time to get them out of the yard. We then rake the manure into the grass or under the bushes for fertilizer. This approach to lawn care might not fit the conventional idea of what a lawn should be, but it is a truly appropriate way to manage a lawn here in the west.
Of course, there is also the potential to stimulate the germination of new seedlings to tighten up a lawn by similar techniques to those used in pasture restoration. For example, you broadcast grass seed over the bare patches when the ground is nice and moist in the spring. Then bring the horses in and feed them hay, so that they trample seeds and organic matter into the soil. Yes, it might make a muddy mess of the yard for a few weeks, but it will help to make a tighter lawn that looks better through the rest of the growing season and the dormant seasons.
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