The shoes a horse wears for ice harvesting are, at their core, the same as any other shoes worn by that individual horse all year. Horses are shod for three reasons: protection, traction and to change the way they move. These are year-round concerns and if a horse has problems with all three, the farrier will adjust the shoe to address all three problems, summer or winter. The difference between summer and winter shoes is what they are made of, and the various pads and traction devices that can be added to them to solve winter problems. All three main factors, protection, traction and movement, come into play when the farrier adjusts shoes for ice harvesting. Working horses need their hooves protected from excess wear caused by hard, slippery winter surfaces. To help with this, the farrier may add padding, make the shoe from a less slippery material and attach protuberances to the shoe for traction. Ice buildup in the hoof, which affects balance and gait, can be prevented by special pads.
Shoes for Protection
In winter or summer, when horses are worked frequently on hard surfaces, their hooves can wear down and their feet get sore. To prevent this, horses wear shoes. Heavy draft horses, like the kind commonly used for ice harvesting, can get sore from pounding on pavement or other hard surfaces like ice all day. To protect them, pads between the hoof and the shoe provide further cushioning. In this respect, winter shoes are not much different from summer shoes with the possible exception of what they are made of. Aluminum shoes provide better traction than the iron, steel, rubber or plastic shoes sometimes used in the summertime. Because of this, aluminum shoes are the most common winter shoes.
Devices for Traction
Slippery surfaces are dangerous for horses, especially for horses pulling heavy loads. To help with this, the farrier adds traction devices to the shoes the horse needs for protection and to help adjust for gait and hoof shape. It is these traction devices that are the most obvious characteristic of winter horseshoes. Traction devices can take many forms: special nails, heel/toe/jar calks, grabs, cleats, swedges and Memphis bars. However, the three most common ways of adding traction are "borium" spikes, screw-in studs and nail-in studs. "Borium" is tungsten carbide shaped into a soft steel rod 1/8- to 1/4-inch thick. The farrier heats the end, welds it onto the shoe and pulls it away to form a spike, much like the shape of a chocolate kiss. This is done after the shoe is fitted for the horse but before the horse is shod. It cannot be done while the shoe is on the horse. The farrier can add screw-in studs to the shoe after the horse is shod. Screw-in studs have the added benefit of being removable (much like chains on automobile tires). Nail-in studs are a third common option that the farrier can add after the horse is shod. Nail-in studs cannot be removed.
Pads for Balance and Gait
Shoes can correct problems with a horse's hoof shape and gait. Some horses need this year round. Other horses may only have a problem called "snowballing" in the winter. Mixtures of snow, ice, mud, manure, grass or bedding can get trapped behind the shoe and accumulate in the sole of the horse's hoof. The effect is that the horse is trying to balance on four icy snowballs. This creates extra strain on its fetlocks and legs. To solve this, the farrier adds a pad made of plastic, synthetic rubber, sorbothane or leather to make removal of ice easier. This is done in addition to any corrective shoes that the horse may need all year.