Horses Chewing Wood

It is quite common for horses to chew on wood. One needs to correct this behavior as it can affect the horse's health (e.g splinters stuck in gums or teeth, swallowed splinters damaging stomach or intestines). Also, over time, this can result in substantial damage to wooden items (stall, fencing, trees). Fortunately, this behavior is usually relatively easy to correct and the short-term risk to the horse's health is relatively low in most cases.

The first step is to confirm that the problem really is the horse eating wood and not the more serious condition of cribbing. In the former case, the horse is actually nibbling on the wood. In the latter case (cribbing) the horse is not eating the wood but simply gripping the wood with its teeth, then arching its neck and sucking in air. Both will leave behind the same evidence of damaged wood but if you watch the horse the two activities are completely different. This article deals with the issue of horses eating wood; if your horse's problem is cribbing you will need to look at our separate article on this, as it is treated differently.

Causes

There are three possible causes of this problem:

  • Boredom. This is the most common cause. Horses which are confined to stalls much of the day, with little to do, simply do not have enough mental stimulation. Lacking anything else to do, they start chewing on wood.
  • Stress or Nervousness. Many people chew their fingernails (or pencils or other items) when they are under stress or nervous. Likewise, a nervous or stressed horse will often look for something to chew on to distract itself. After it has eaten all the food in its stall, it may then turn to the wood.
  • Nutritional Deficiencies. If a horses food does not contain all the minerals and other nutritional elements which it requires, it will look around for something else to eat. It may chew on earth, trees or wood.

Stop Horse Chewing Wood

Part of the treatment is fixing the underlying cause:

  • If the behavior is due to boredom, one needs to provide a more stimulating environment.
  • If it is due to stress, one needs to identify what is causing the stress and then correct it. For example, older or weaker horses are somtimes bullied by other horses, in which case one may need to separate the bully and the victim.
  • For nutritional deficiencies, one needs to provide whatever the horse is missing. As a general rule, one should provide both salt (e.g. a salt lick) and minerals (e.g. a mineral stone). Try this as the first step and monitor the behaviour to see if there is an improvement. If you are already providing minerals and salt and it doesn't help, the next steps would be to take the advice of a veterinarian and/or have your pasture tested for nutritional completeness.

In some cases is can be difficult to know which of these three possibilities are the cause. In this case, one needs to observe the horse over time to see if the chewing occurs in times of boredom or times of stress. Knowing when a horse chews wood is a useful indicator of the possible cause and potential treatments. For example, if a horse chews wood throughout the day, the problem is likely related to general boredom or stress. Alternatively, if the horse chews wood at specific times or under specific circumstances (e.g. at grain feeding time), the problem is likely more specific (e.g. fear that it won't get fed or that the other horses will eat all the grain before it can get some) and so is the associated treatment (e.g. feeding the problem horse separately, feeding the problem horse first).

One can also try all the above solutions (more stimulating environment, stress reduction, salt and minerals) in parallel with any specific actions (e.g. changing feeding routine if the behavior is due to feeding related stress), as they are good practices in any case.

One also needs to be aware that once a horse starts eating wood, it eventually becomes an ingrained habit and the habit will tend to continue even after the underlying cause is addressed. Fixing the cause will normally reduce the extent of the habit but often will not stop it. Consequently, one needs to address the habit aspect of this behaviour as well as the original cause.

  • There are a number of products which one can spray or paint on wood, to give the wood a very unpleasant taste. As the taste gradually fades (expecially with outside wood exposed to the rain), one needs to periodically repaint the wood until the habit is corrected.
  • For paddock and pasture fencing, the amount of paint required may be excessive. An alternative approach is to put an electric fence wire (under current) along the top of the fence boards.
  • If the eating occurs in a limited area (e.g. stall doors), one can fasten a metal strip to the top of the wood. While quite effective, one needs to make sure that this actually stops the horse since if he persists in trying to chew on the wood under the strip (unlikely but not impossible if the habit is deeply ingrained), the metal could damage his teeth.
  • Some owners report that their horses have responded very well to calming medications which were perscribed by their veterinarian.

Diet is also an important consideration. In a natural environment, horses spend much of their day chewing. Foods such as grain or pellets which are eaten quickly with little chewing do not satisify the horse's natural chewing behaviour. By feeding the horse with hay or other chewy foods can be useful as part of the treatment. Some owners report that late-harvest hay, which has hard stems and requires more chewing, is particularly beneficial in this regard.

Treat Both Cause and Behavior

A common mistake is to treat the cause or the behavior but not both. If one treats the cause (e.g. boredom) but not the behavior (e.g. by painting the wood or using an electric wire) then the habit may continue even though there is no longer any reason for it. Alternatively, if one treats the behavior (e.g. by wood paint or electric wire) but not the cause, one may stop the horse from chewing wood  only to find that he then develops a different behavioral issue in response to the continuing underlying problem.