Hay vs haylage: what's the difference?

Hay and haylage are both preserved grass forages and both can form the basis of a horse's diet.

The difference is mainly in how they are made and how much moisture they contain.

Hay is dried much more thoroughly before it is baled. Haylage is allowed to partially dry before being wrapped to keep air out.

That difference affects how the forage is stored, how much you need to feed and, often, its nutritional value.

Hay vs haylage at a glance

Neither is automatically better.

The quality and nutritional value of the individual batch matters far more than whether the label says hay or haylage.

What is hay?

Hay is grass that has been cut and dried before being baled.

It needs sufficiently dry weather during production so that enough moisture is removed before storage.

Good hay should be clean and suitable for feeding, without obvious spoilage or contamination.

Because hay contains relatively little moisture, it can be stored for long periods provided it is kept somewhere dry and well ventilated.

The downside is that dry hay can contain more airborne dust than haylage, particularly if its quality is poor.

What is haylage?

Haylage is also made from grass, but it is not dried as thoroughly.

Instead, the grass is allowed to wilt before being baled and wrapped in plastic. Removing air from around the forage allows it to be preserved.

Haylage is often cut earlier than hay and can therefore be more digestible and provide more energy and protein.

That is common, but not guaranteed.

Different haylages can vary enormously depending on:

• the grass used
• when it was cut
• how dry it was when baled
• how it was produced
• how it has been stored

Forage analysis is the only reliable way to know exactly what a particular batch contains.

Is haylage the same as silage?

No.

Although both are wrapped forage, horse haylage is generally much drier and undergoes much less fermentation than typical agricultural silage.

This is also why the idea that properly produced haylage is "too acidic" for horses is misleading.

Good quality horse haylage is a widely used and suitable forage.

Do you feed the same weight of hay and haylage?

No.

This is one of the biggest practical differences between them.

Haylage contains more water, so a kilogram of haylage contains less actual dry forage than a kilogram of hay.

For example, if:

• hay is 85% dry matter
• haylage is 65% dry matter

then 10kg of each does not provide the same amount of forage.

To provide 10kg of dry matter you would need roughly:

These percentages are examples rather than fixed values. Actual moisture content varies considerably between batches.

The important point is simple:

Do not swap 10kg of hay for 10kg of haylage and assume the horse is receiving the same amount of forage.

If you are unsure how much forage your horse should be eating in the first place, see our How much hay does a horse need? guide.

You can also use our Horse Weight Estimator if you need an approximate bodyweight before working out a daily forage allowance.

Is haylage higher in calories?

Often, yes.

Haylage is commonly cut earlier than hay, when the grass is more digestible. This can result in a forage containing more usable energy and protein.

That can make good quality haylage useful for horses that struggle to maintain weight.

It can also mean it is not the best choice for every good doer.

A native pony that gains weight easily may do better on an appropriate lower energy hay than a rich, highly digestible haylage.

However, you cannot reliably judge calorie content from appearance alone.

Two batches of haylage can be very different.

Is haylage lower in sugar than hay?

It can be.

Haylage is often lower in sugar than hay because some sugars are used during the preservation process.

But lower sugar does not mean lower calorie.

Haylage can still provide more digestible energy than hay because it is often made from younger, more digestible grass.

This is particularly important for horses that are overweight, prone to laminitis or have equine metabolic syndrome.

Do not choose forage based on the word "hay" or "haylage" alone. If sugar and energy levels are important for your horse, forage analysis is much more useful.

Speak to your vet or an appropriately qualified equine nutritionist if your horse has specific dietary requirements.

Is haylage better for horses with respiratory problems?

It can be.

Because haylage contains more moisture, it generally produces less airborne dust than dry hay.

This can make good quality haylage a useful option for horses with equine asthma or other respiratory problems.

Hay can also be managed to reduce respirable dust, commonly by appropriate steaming or soaking.

If your horse has an ongoing cough or breathing problem, speak to your vet rather than simply changing forage and assuming the problem is solved.

Which is better for a good doer?

Hay is often easier to incorporate into a calorie controlled diet, particularly where a suitable lower energy hay is available.

Hay can also be soaked where appropriate to reduce its water-soluble carbohydrate content.

Haylage is not automatically unsuitable for good doers, but some batches can be relatively energy dense.

If weight management is important, the nutritional content of the forage matters more than its name.

Regularly monitor your horse's weight and body condition rather than waiting until a change is obvious.

Our Horse Weight Estimator can help you track approximate bodyweight consistently.

Which is better for a poor doer?

Haylage can be useful for horses that struggle to maintain condition because it is often more digestible and energy dense than hay.

It is also usually softer and more palatable, which may help horses that are reluctant forage eaters.

However, unexplained weight loss should not simply be treated by feeding richer forage.

Dental problems, parasites, illness and other conditions can all cause weight loss, so speak to your vet if your horse is losing condition unexpectedly.

What about storage?

Hay needs to be stored somewhere clean and dry.

If it becomes damp during storage it can deteriorate and develop mould.

Haylage is protected by its wrapping while unopened and can often be stored outside, but the wrapping needs to remain intact.

Avoid puncturing wrapped bales during handling or storage.

Once a haylage bale is opened, air can reach the forage and it will begin to deteriorate. It therefore needs to be used relatively quickly.

How long an opened bale remains suitable depends on the product, temperature and storage conditions, so follow the supplier's guidance.

Do not feed spoiled or contaminated forage.

Switching between hay and haylage

Make the change gradually.

A horse's digestive system depends on microorganisms in the hindgut, and these need time to adjust when the diet changes.

Where practical, introduce the new forage progressively over around 10 to 14 days, replacing more of the old forage each day.

This is particularly important if you are also changing the overall energy or nutritional content of the diet.

What should you buy?

There is no universal winner.

Choose hay if it suits your horse's nutritional needs, you can store it somewhere dry and dust is not a major concern.

Choose haylage if you want a lower dust forage, outdoor bale storage is useful, or your horse benefits from a more digestible forage.

But always judge the actual forage in front of you.

Good hay is better than poor haylage, and good haylage is better than poor hay.

Planning your forage

Once you know what you are feeding, StableMetric can help with the numbers.

• Use the Horse Weight Estimator to estimate your horse's bodyweight.
• Read How much hay does a horse need? to work out a starting daily forage requirement.
• Use the Winter Forage Planner to estimate how much forage you may need to buy for the winter.
• Use the Hay Cost Calculator to estimate what your forage supply is actually costing.

The simple answer

Hay is drier and easier to store once opened.

Haylage contains more moisture, is usually lower in dust and is often more digestible, but needs to be fed at a greater weight and used more quickly after opening.

Neither is inherently better.

The right choice depends on your horse's weight, health, workload and nutritional needs, along with the quality of the forage available to you.