Published June, 2012

When it comes to creating the best environment for their horses, owners have a lot to think about. However, what lies beneath their animals' feet generally isn't one of them, said Stephen Higgins, PhD, director of Environmental Compliance for the Agricultural Experiment Station at the University of Kentucky's College of Agriculture. Even so, he said creating surfaces that minimize pastures damage and reduce horses' health risks should be on owners' priority list.

Higgins explained that when a horse is standing, his hoof places approximately 27 pounds of pressure per square inch (PSI) to a surface. That surface pressure increases to 48 PSI when a horse walks. When several horses congregate around soft surface feeding and watering areas they can create mud. Over the long term, heavy equine traffic on muddy surfaces increases soil compaction, prohibits the growth of desired vegetation, and promotes weed infestation. These muddy conditions also expose horses' hooves and legs to bacterial infection and force animals to expend more energy, in turn increasing their need for feed, water, and forage.

It's better, said Higgins, to provide animals with an all-weather, multipurpose surface that can support the weight and continuous traffic near gateways, feeding areas, and other places horses congregate. These so-called "hardened surfaces" incorporate heavy-use pads or compacted gravel around concrete near high-traffic areas. Owners can create hardened surfaces by installing geotextile fabric in high-traffic areas, then covering that material with gravel.

Made from polypropylene or polyester material, geotextiles are permeable fabrics used to strengthen soil and reduce erosion. Used in combination with gravel (also called dense grade aggregate) geotextile fabrics create a surface that can withstand heavy traffic from horses, humans, and farm equipment and other vehicles.

Placing the fabric before adding gravel is crucial to the surface's long-term performance, Higgins said. "If the geotextile is not used, the rock material will sink into the ground over time and mud will seep up through the voids, eventually creating the same problem the pad was built to remedy," he said.

The combination also has construction-related economic benefits. "The use of geotextile fabric allows area pads to be constructed using much less gravel because the fabric acts as reinforcement," Higgins said. "This means that these pads can be constructed using less rock than if rock alone was used."

Owners can also construct hardened surfaces using footing materials that will self-harden such as soil cement, lime stabilized soils, or coal combustion products. Higgins advised against using Class I sand to create a hardened surface unless dense grade gravel is placed beneath it for support. Typically, gravel pad installation requires placing the pads, getting them wet, then compacting them with a smooth drum roller. Soil cement and coal combustion products should be allowed to cure for about seven days before use.

Local conservation district personnel can advise horse owners about which materials are readily available locally. They can also advise owners about local best practices for installing hardened surfaces, Higgins said.

Once in place, owners should maintain hardened surfaces by removing any deposited manure or uneaten hay, Higgins said. "Owners should try not to scrape up the gravel (when removing manure and uneaten hay)," he said. "But it's hard to avoid some removal."

Assuming normal wear and tear, owners should top-dress the pad with gravel, water it down, and compact it once every five years, he said.

Finally, owners who install hardened surfaces not only create better environments for their horses, but also comply with state and federal agricultural air and water pollution regulations, Higgins said. And there's a cost benefit, too. "Considering the reduction in feed costs and reduced risk of disease, doing the environmental stuff increases your production," Higgins said.

Pat Raia is a professional journalist who has covered horse industry and equestrian topics for a number of publications. Her background includes riding, showing, and training Saddlebred horses.