Tour the grain belts of the world and you'll find plenty of barley. It's a poor performer in hot and humid areas. It doesn't care much for wet feet, either. But if you live in a region with a reasonably low rainfall and a moderately short growing season, there's a good chance you'll find plenty of fields of barley.

Its importance in the diet of horses will depend very much upon availability. In the United States, for example, barley production is only a twentieth of corn. More and more farmers are turning to different crops to satisfy the local biofuel industry.

A significant portion of the US crop goes to the brewing industry, so many horse owners will be looking for other grains.

But if barley is big in your region, it will likely be big in locally produced feeds. Or, as many do, you might sacks of barley and feed it yourself.

So how does barley measure up in the equine diet?

Barley lies in the middle ground between oats and corn. By weight, barley provides more digestible energy and total available nutrients than oats, but it doesn't quite reach the levels of corn.

Many horse owners prefer barley over oats because the former is less likely to trigger "hot" behaviour.

It's considered a good feed for putting condition on a horse, but it's certainly not the perfect feed. It has a poor phosphorous/calcium ratio (Corn and oats aren't great either, but barley is the worst of the three). It also lacks vitamins A and D, so alternative sources will need to be found by horse owners.

The grains of barley are very hard and need to be crushed or rolled, or cooked before feeding. It should never be crushed too finely, and, when cooked, it's generally best to do so without crushing or rolling.

The result can be a gluggy mass of food that runs the risk of packing down in a horse's stomach and triggering a colic attack. Like many grains, it simply does not have the bulk that a forage diet provides - and that is bulk critical to the normal function of a horse's digestive tract.

The answer is to mix the barley with a bulkier feed such as sugar beet pulp, chopped hay or wheat bran, lucerne chaff, even rolled oats, ensuring the bulkier feed comprises 15 to 25 per cent of the mix.

Some horses dislike the taste of barley. It will generally be more palatable when cooked, or by adding molasses.

It's important to remember also that each grain of barley locks in its nutritional value. As soon as you crush a grain, the nutritional value will begin to decline.

Crushing your own and then feeding it will result in more nutritional value getting to the horse. A bag of crushed barley fed out over two weeks will have considerably less food value after a few days.

There's a big variation in the quality of barley, too. Quality barley will be a pleasing pale-golden colour. The grains will be of uniform size and undamaged. There should be a minimal amount of fines - dust and other debris - in with the barley.

Source the best possible barley you can. As with most horse feed, you're generally better off to pay more for the best quality, rather than saving money by compromising on quality.

Price will vary, depending upon how far the grain has to be trucked.

Barley's nutritional value

• Calories: 3350 to 3600 per kilogram
• Total digestible nutrients: About 82%
• Crude protein: 14%
• Crude fibril 6%
• Digestible protein: 11.5%
• Calcium: 0.05%
• Phosphorous: 0.38%