Gravel: The simple solution that is “not simple.”  

sacrifice areaAfter one of our wettest, muckiest winters on record, Marylanders are girding their loins for an equally mucky wet spring. Many horse farm owners are looking for simple solutions to that perennial scourge of scourges: mud. Deep boot-sucking, tractor-sucking, soul-sucking mud anywhere the horses congregate; mud that sucks off shoes, twists stifles and destroys any hope of future pasture.

One seemingly simple solution is to just throw some gravel down, and the local gravel pits tell

us that their phones hum this time of the year with requests from farmers for gravel.

But, like so many things in life which seem simple but are not, gravel is not simple.

Put the wrong gravel down, or lay it incorrectly, and you’ve created more problems then you have solved.

The wrong gravel can lead to stone bruises and abscesses. Thoroughbreds in particular are vulnerable to stone bruising, and as Thoroughbreds are the most common breed in Maryland (in addition to being the official state breed), farriers in Maryland are quite skilled at providing solutions! (From The Horse magazine):

Thoroughbreds, for example, have been bred for speed for many years. Often, other highly heritable qualities–such as good, solid hooves–have been ignored in the quest for that elusive quality called speed. In many cases, these thin-soled horses are able to exist and perform with few problems because they are exercised on smooth surfaces that are devoid of rocks and other sharp objects. However, when they are placed in an environment where they must travel across a rocky surface, their feet often are unable to cope. Stone bruises and lameness are the result.   

sacrifice areaMake smart choices about your gravel, so that you don’t solve one problem just create another problem, which could lead to an unending cycle of lameness and farrier bills.

Incorrectly installed gravel can lead to more maintenance problems, a never-ending sisyphean task that perhaps would have been unnecessary had the farm owner merely had the patience to let nature take its course. Are you installing the gravel in a wash or a run-off area? Is it an area that is prone to an annual flood or two? If so, that stone is just going to end up washed through your pastures.

Laying gravel for horses is not like laying gravel in a parking area. While the rolling of tires will gradually pack down and harden a gravel path, horses punch holes into gravel. Gravel installed without a sufficient base will merely get churned up, so now you have rocky, muddy hole instead of just a mud hole.

Finally, there are the trade-offs to consider. While the gravel area is a useful solution during the non-growing season, what happens once grass–and weeds–start growing? Will you forever be wrecking or sharpening mower blades? Obviously, where the gravel is the thickest, pasture will not grow, but something will grow. Weeds. And lots of them, particularly in a patch of hastily installed gravel. How will you deal with those weeds? More poisons and herbicides around your horses? Are you going to take a weed whacker to a patch of gravel?

sacrifice areaSo before you play whack-a-mole, trying to fix today’s problem only to create more problems for tomorrow, contact your local cooperative extension agent or soil conservation agent. Site consultations are free, and they can save you a lot of future headaches not to mention money. Your agent will review your particular farm’s needs, from the lay of the land and the soil type to your pasture use and herd management, and the agent will first look for lower cost solutions to your problem, such a moving a gate to a higher spot.

If gravel does seem to be the most practical solution, your cooperative extension agent will help you determine if it makes more sense to install patches of gravel in certain high-use areas in a pasture, or if you should install what is known as a “heavy-use paddock,” also known as mud paddocks and sacrifice paddocks. These are smaller turnout paddocks that are all gravel on which horses can be confined on wet or muddy days, but also during times of drought when grazing the pastures further will damage them. Obviously, in all cases, horses will have to be hayed.

If you choose to install patches of gravel, your soil conservation agent will help you determine the most appropriate type of gravel mix for your soil and for the lay of your land. Be careful about using any advice you find on the internet. What gravel mix works in the sandy soil of southern Maryland is not going to be as effective on the thick clay found at higher elevations.

Properly installed heavy-use paddocks can help you successfully manage both your horse farm and the health and well-being of your horses.

Obviously, soil conservation agents are not your only resource. A pasture management specialist can also work with you on creating the best solutions for your particular situation, as well as many (although not all) excavators. If you do not own the necessary heavy equipment to install gravel, you will most likely need to hire an excavator. A word to the wise: don’t tell your excavator what to do…explain to him (or her) the problems you are trying to solve. A good excavator will work on helping you find the solutions, and keep you from making costly mistakes that will require ongoing repairs. Other excavators will just shrug and take your money, and roll their eyes at the stupid horse people.

Tips on Building Sacrifice Areas & Mud Paddocks

Sacrifice Areas: Arenas and heavy-use or designated sacrifice areas should have a well-constructed subsurface or base to support the soil and water filtration under heavy use. Surface footing types include:

  • Sand: Where soils are primarily sand, it can be used through the full depth of the sacrifice area. It can be dusty in summer months, so consider using “washed” arena sand to minimize the need to wet it down.
  • Hog fuel: large wood chips can be used for the base layer but will break down quickly. Shredded wood used for surfacing also breaks down quickly but can make a resilient surface.
  • Gravel: The size of the base layer depends upon the soil type. Heavy clay soils may need several lower inches of large gravel with a finer grade above, e.g., 3/8 to 5/8 inch, and a finer third surface layer. Each layer should be separated with fabric to prevent migration of the particles.

Subsurface: Geotextile cloth or filter fabric should be installed between the different layers of the base and surface materials and at the subsoil level. A perforated drainage pipe system may be needed, depending on the percolation capability of the subsoil.

Building a Sacrifice Area

Tips from Maryland’s Cooperative Extension & Soil Conservation Districts  

Mud can be a big problem wherever animals congregate, especially around gates, water troughs, barn entrances, and feeding pads. If mud in these areas is making you and your horses miserable, heavy-use pads may be a solution.

  • The main components of a heavy-use pad–stone plus landscape fabric–allow water to slowly drain away without mixing with dirt. They are simple to install if you have a front-loading tractor and can do simple excavation work. If not, you might want to hire someone with the necessary equipment.
  •  Don’t skimp on the size of the pad. If you’re installing one around a trough, make it at least the length of one horse on each accessible side of the trough.
  •  To give your pad the best chance of working, first divert any water, such as from barn, shed and house downspouts, so it moves around, not through, the area. Downspout extenders and shallow berms are two easy ways to reroute water.

To construct a heavy-use pad:

  • Excavate to a depth of 8 inches and level the site.
  • Install landscape fabric. If the fabric isn’t wide enough, overlap edges by at least 12 inches.
  • Install 6 inches of #2 stone (about 2 1/2 inches wide).
  • Compact stone by driving over the pad with tractor.
  • Install 3 inches of CR6 or CR8 stone. (CR6 ranges in size from dust to 3/4 inch wide. CR8 is even smaller.)• Compact and level stone.
  • Inspect regularly and repair as needed.

Heavy-Use Area

Materials calculations:

  • 10 feet x 10 feet = 100 square feet
  • Landscape fabric = $(0.50/sq.ft.)
  • #2 stone, 6 inches deep = 50 (cu.ft.) @150 (lbs./cu.ft.) = 7,500 lbs. = 3.75 tons
  • CR6 or CR8 stone, 3 inches deep = 25 (cu.ft.) @ 150 (lbs./cu.ft.) = 3,750 lbs. = 1.875 tons

Contact your local Soil Conservation District; they can help you design–for FREE–a pad that is right for your situation!