Why Horses Chew Wood

Horse crib biting on fence.

Ken Gillespie Photography/ First Light /Getty Images

Do your fences look like they've been attacked by an army of termites? Are there dead trees in your pastures because rings of bark have been chewed off of the trunks?  Do your stalls have 'decorated edges' that make them look like they were edged with a giant pair of pinking shears? But of course, termites or pinking shears aren't the real culprits. Your horses will have been responsible for this very common problem. There are a number of reasons why horses chew wood. And there are a number of solutions you can try, depending on the root of the problem.

Why do Horses Chew on Wood?

There are basically three reasons why horses chew wood:

  • Boredom or Frustration
  • Nutritional Deficiencies
  • Habit

Horses kept in stalls, small paddocks, secluded from other horses, or fed largely concentrates, without enough fodder to keep them chewing over a long time may become bored and chew fences for something to do. Very occasionally vitamin deficiencies may cause a horse to have pica—a taste for eating strange foodstuffs in an effort to alleviate the deficiency. And some horses may have learned to gnaw wood from stable or pasture mates. Like mischievous kids, they try what the other kids are trying, even if they would never have thought of it on their own—and the habit sticks. Horses that crib or windsuck can be hard on wood (and other surfaces too). However, this isn't truly wood chewing and the solutions aren't quite as easy.

Why Is Wood Chewing a Problem?

It's very frustrating to put up beautiful board fences only to have them chewed down to thin sticks with scalloped edges within a few months. Not only is fencing costly to replace or maintain, but the slivers and splinters can cause injury to your horse's mouth and digestive system. Enough wood chips in your horse's gut and you could be facing a nasty case of colic. Damaged trees may die if their bark or branches are constantly stripped. And of course, indoors, the damage may be as frustrating and costly too.


 One old-time remedy to prevent horses from chewing wood was to feed them bone-meal. Although it was a guess, they were fed bone-meal because it was felt that the horses were lacking calcium. Now there's no reason to guess if your horse is missing out on an important mineral or vitamin. If you suspect pica, you need to have your veterinarian draw a blood sample and find out exactly what nutrients your horse may be missing. This way, you can supplement with the exact vitamin or mineral in the correct amounts. Guessing what the deficiency is may lead you to over or under supplement your horse, which could be throwing your money away and not solving the problem. It also can lead to the creation of another problem.

Horses that are kept indoors are more likely to develop habits to alleviate their boredom and frustration. Outdoors, some horses may get bored because there may be little to do once their hay is eaten up. Horses in the wild spend the majority of their time grazing. When we keep them cooped up, restrict their diets, keep them from being with other horses or don't provide them with enough room to self-exercise our horses may find other ways to vent their frustration and show their boredom. Allowing horses to live as naturally with other horses as possible, outdoors with plenty of grass or hay to nibble on can prevent wood chewing.

When Turn Out Isn't An Option

Unfortunately, there are times when outdoor turnout 24x7 isn't possible, such as when a horse has an injury requiring stall rest, there isn't space or resources for all day turn-out or conditions such as icy pastures make it dangerous for horses to be out. Some horses will become obese or even develop health problems if left with food all day and simply can't be left to eat non-stop. In these cases, you may have to take measures to protect your wood surfaces.

The first thing many people try and the least expensive solution is sprays, pastes or washes that have a bitter taste painted onto the wood surfaces. The downside of these is that they get washed off in the rain, and some horses don't seem to notice the taste. Metal caps can be nailed over fence rails and posts and protection can be wrapped around trees. Plastic mesh can be used as well. A string of electric fencing along the top rail of a fence will usually keep determined chewers back and little pens can be set up around trees to prevent horses from getting near enough to chew.

Wood chewing is a fairly easy problem to solve and finding the right solution can save you money, as well as ensure your horse's good health.