Essential Horse Analysis: What you need to know

Horse owners new to analysis testing often face the same question: which test do I actually need?

This guide covers the three core analysis services Forageplus offers: forage, soil and water, explaining what each one tells you, when you need it, and how to avoid paying for a test that won’t actually answer your question.

Forage Analysis

What does forage analysis tell you? (Mineral vs. nutritional)

Forage analysis is the only reliable way to know exactly what your horse is eating, and what it’s missing.

Bagged feeds that claim to be “balanced” are only balanced to themselves. Most are built around a generic vitamin and mineral premix, not matched to the hay, haylage or grass your horse actually eats. Only testing your forage can tell you what your horse’s diet genuinely needs.

Forageplus offers two core types of forage analysis, and knowing the difference matters:

Mineral analysis tells you the levels of calcium, magnesium, phosphorus, zinc, copper, iron, manganese and other essential minerals in your forage, along with antagonist minerals like aluminium and lead. This is the test that identifies deficiencies and imbalances in your horse’s mineral intake.

Nutritional analysis tells you the sugar, starch, protein and digestible energy (calorie) content of your forage. This is the test that matters most for laminitis-prone horses, good doers, and horses needing to gain or lose weight.

Which one do you need? It depends on your horse:

• If your horse is turned out 24/7 with grass as the main part of the diet, a mineral analysis is usually enough.
• If your horse eats a significant amount of hay or haylage (50% or more of the diet), you should test both mineral and nutritional levels.
• If your horse is laminitis-prone or a good doer, start with a nutritional analysis to check sugar and starch levels, then follow up with a mineral analysis.

Mineral Analysis for Horses

When is the best time to take a grass sample? Timing matters less than most owners expect, but a few practical points are worth knowing.

Sampling is hardest in winter, since grass growth slows and grazing can leave the sward very short. Take your sample when the grass is at least 2cm long, so you’re getting a genuinely representative cutting.

Weather can shift mineral levels slightly, rainfall affects iron and manganese, a cold spring affects phosphorus in summer grass, and new shoots run a little higher in potassium and lower in magnesium, but none of this is significant enough to justify testing more than once or twice every couple of years. A mineral analysis reflects the overall pattern of your pasture, and that pattern holds true year-round.

The one exception: after you’ve treated your soil. If you’ve added manure, fertiliser, minerals or lime, retest once the new growth has come through. That’s the only situation where more frequent testing genuinely earns its keep.

Can’t get a representative sample? A Forage Focused™ horse feed balancer is the next best option. These are formulated directly against the pattern of deficiencies and excesses found across the thousands of forage samples in the Forageplus database, so they’re targeted to common UK forage gaps, rather than built on a generic, broad-spectrum assumption.

Nutritional Analysis for Horses

NIR vs. Wet Chemistry: which analysis method is best?

Once you know which test you need, you’ll also see a choice of testing method, NIR or wet chemistry. Here’s the difference.

NIR (Near-Infrared Reflectance) uses a spectrophotometer to analyse the light spectrum reflected off a sample under infrared light. Each nutrient reflects light differently based on its molecular structure, and this reflectance is compared against a calibration set of samples already analysed by wet chemistry.

NIR is faster and cheaper than wet chemistry, and requires less lab labour. With sophisticated calibration and quality control, it remains highly accurate for most forage testing needs.

Wet chemistry uses chemicals and heat to physically break down and isolate nutrients from the forage. For example, testing fibre content involves boiling a sample in a neutral detergent solution, then measuring the difference in weight before and after.

Wet chemistry is more time-consuming, more expensive, and requires skilled technicians to carry out. Some owners prefer it for the reassurance of a direct chemical measurement, but NIR is highly accurate for the vast majority of forage testing situations.

In short: NIR is quicker and more cost-effective, and accurate enough for almost all owners. Wet chemistry is a reasonable choice if you specifically want direct chemical verification, but it isn’t necessary for most forage testing needs.

Do I need to test nitrate levels in horse forage?

If you test your hay or haylage for both nutritional and mineral content, you’ll already get an indication of whether nitrate levels could be a problem. If you’re only testing for nutritional elements, you may want to add a nitrate test to rule this out.

Test for nitrates if:

• Your hay or haylage has a protein level above 14% and calcium below 0.9%
• You’re feeding hay or haylage to a pregnant mare, since high nitrates can affect the developing foetus

High nitrates paired with low calcium can also mean poor-quality protein, even in hay under 12% protein, which may show up as poor muscling, or hoof and skin quality problems.

Read our full guide to nitrate toxicity in horse hay and haylage for a complete breakdown of causes, risks and testing.

Can analysis tell me if I need to soak hay or haylage?

Testing dry hay or haylage will tell you whether you need to rinse and soak it to lower sugar levels for your horse.

Soaking isn’t always the right call. The process washes out soluble nutrients too, including sodium, magnesium and B vitamins, alongside the sugar. Testing first means you can avoid soaking unnecessarily, saving time and keeping your hay more nutritious.

Many hays don’t need soaking at all. A large proportion of the hay we test comes back below 10% combined ESC and starch, already within the safe threshold without any soaking required.

Soaking can go too far. If the carbohydrate level drops below 6% after soaking, this can be detrimental to your horse’s performance, energy and health.

If you test both a dry and a soaked sample, you can confirm exactly how much sugar has been removed, useful for peace of mind, or for horses and ponies who need particularly careful management.

Can’t test? Soak for a maximum of two hours. Our database of forage samples shows most hays will be low enough in simple sugars within that time. Soaking for longer than necessary only increases the loss of valuable water-soluble minerals and vitamins.

Read our full Ultimate Guide to Soaking Horse Hay for a complete breakdown of timing, technique and what gets washed out.

Can I get a nutritional analysis of grass for horses?

We can test grass nutritionally, but for most owners, we don’t recommend it. Here’s why.

Most owners want a grass nutritional test to answer one question: is the sugar level safe for a laminitis-prone horse? The problem is that grass sugar levels change constantly, hour by hour, not season by season.

Sugar in grass is affected by:

• Time of day (lowest overnight, highest in the afternoon)
• Sunshine and cloud cover
• Temperature, both day and night
• How long the sample takes to reach the lab, since the grass keeps photosynthesising in transit

Even freezing a sample in liquid nitrogen or flash-drying it in a microwave the moment it’s taken, the only ways to get a genuinely accurate reading, only capture sugar levels at that exact moment. It tells you nothing reliable about an hour later, let alone the following week.

The practical answer: rather than testing grass sugar, manage exposure directly during known high-risk periods.

• Highest risk: late morning through early evening
• Highest-risk months: typically March to late July, with some horses also needing care in September and October
• Some horses can’t tolerate grass safely at any time of year, and may need to be managed off grass entirely

Protein and calorie levels in grass change far less than sugar, highest in early to mid-spring, but still shift within weeks. Because of this, we don’t offer nutritional testing of grass as a standard service.

If you’d still like a nutritional test of grass carried out, contact us, we’re happy to help, we just want you to know what the result can and can’t tell you first.

Soil Analysis

If your horse’s grazing itself, rather than the hay or haylage you buy in, is the problem, the issue may start in the ground, not the grass.

Choose a soil analysis if you own or can apply treatments to your horse’s pasture. A soil test tells you what your soil needs in order to grow healthier, better-balanced grass. It cannot tell you what to feed your horse directly, that’s what forage analysis is for, but it addresses the problem at its source rather than after the fact.

Our soil analysis is based on the Albrecht method, and looks at the balance of minerals in your soil rather than treating every field the same way. This approach is particularly suited to horse pasture, which is often compacted and overgrazed in ways conventional agricultural testing doesn’t account for.

Why it’s worth the investment: correcting soil imbalances is a longer-term project than forage testing, changes like liming can take a couple of years to fully shift soil pH and nutrient uptake, but the payoff is grass that’s genuinely better balanced at the source, rather than grass you’re constantly correcting for with feed.

Read our full guide to testing horse pasture soil for a complete breakdown of the Albrecht-Kinsey method, why it outperforms conventional testing, and how to get started.

Water Analysis

Water is the most essential nutrient your horse consumes, accounting for 50 to 70% of total bodyweight. After forage, it has the greatest impact on your horse’s mineral status and overall health, yet it’s the analysis most owners never think to consider.

Do you actually need a water test? If your horse drinks tap water, no. Tap water is already tested by your local provider to ensure it’s fit for consumption, and you can request a report directly from them.

Test your water if your horse drinks from a borehole, spring, pond, river or stream. Unlike tap water, these sources aren’t routinely tested, and mineral levels can vary significantly from one source to the next.

A Forageplus water analysis checks 16 elements, including essential minerals and antagonist minerals like lead and arsenic, alongside pH. This matters for two reasons:

• Safety. Some natural water sources carry heavy metal contamination or other toxins that pose a direct health risk.
• Mineral balance. Even safe water can be naturally high in certain minerals, calcium is a common example, which can interact with the minerals you’re already feeding through forage and bucket feed, potentially unbalancing a diet that otherwise looks correct on paper.

If your water test reveals a mineral imbalance, we can incorporate the result directly into your horse’s overall feeding plan, alongside your forage analysis, rather than treating it as a separate, standalone issue.

Which analysis do I need?

By now you know what each test tells you. Here’s how to put it together for your own horse.

Start with forage analysis in almost every case. It reflects exactly what your horse is eating today, regardless of what’s happening in the soil or water source behind it.

Add soil analysis if you own or can treat your horse’s pasture, and want to improve the grass at its source rather than only correcting for it through feed.

Add water analysis if your horse drinks from a borehole, spring, pond, river or stream, since this is the one variable tap-water-drinking horses don’t need to worry about at all.

If your horse eats a significant amount of hay or haylage (50% or more of the diet), test both mineral and nutritional levels together, rather than choosing just one.

If your horse is laminitis-prone, start with a nutritional analysis to check ESC and starch, then follow up with a mineral analysis once you know the forage is safe to feed.

Choosing the right analysis can feel complicated at first, but you don’t have to work it out alone. Contact us and we’ll help you choose the right test, or combination of tests, for your horse.