Salt, Minerals and the Land

What Wild Horses Teach Us About Nutrition and Pasture Health

Salt is essential to horses. Sodium supports nerve function, muscle contraction, hydration, and temperature regulation. In domestic settings this often translates to buckets, blocks, and supplements (Schryver et al., 2025; Clegg & McBride, 1987). But wild and feral horses manage to meet their mineral needs without human input.

The reason is not resilience or luck. It is access to functioning landscapes.

How wild and feral horses obtain salt and minerals

Wild and feral horses live within mineral systems, not managed paddocks. Their nutrition comes from the land as a whole, not from a single forage source. Many populations regularly visit natural salt licks or exposed mineral rocks. These may be inland deposits, eroded cliff faces, dried lake beds, or naturally saline soils. Horses will travel long distances to access them, often returning to the same sites year after year (Tankersley et al., 2004; Journal of Mammalogy, 2008). These locations provide sodium alongside other trace minerals that work together in balance.

The Camargue, a wetland in Southern France where the Rhône River meets the Mediterranean Sea, famous for its wild landscapes and semi-domesticated white horses. It's a protected natural park, known for its salt production and distinct culture. 

In coastal regions, salt is consumed indirectly through sea spray on grasses, herbs, and shrubs. Even small amounts of salt deposited on plant surfaces contribute to daily intake when horses are grazing for many hours across large areas (Scasta et al., 2016).

Minerals are also obtained through diverse forage. Wild horses consume a wide range of grasses, forbs, herbs, shrubs, tree leaves, bark, and roots. Many of these plants draw minerals from deeper soil layers that cultivated grasses cannot reach. Small amounts of soil are naturally ingested during grazing, particularly in dry conditions or when grazing close to the ground, adding further trace minerals (Muskwa-Kechika Research, 2004).

Movement is critical. Wild horses walk many kilometres each day, grazing continuously and sweating in small, steady amounts. Mineral intake and loss remain in balance because both are spread across time and terrain (Scasta et al., 2016).

Why domestic horses often appear salt deficient

Domestic horses are rarely deficient because they are broken. They are deficient because their environments have been simplified.

Most horse pastures in the UK are dominated by a small number of cultivated grass species bred for productivity rather than nutrition. These grasses are typically high in potassium and sugars, and very low in sodium, magnesium, and trace minerals. Potassium actively increases sodium excretion, meaning horses grazing monoculture swards lose more salt than they consume.

Add restricted movement, intermittent exercise, conserved forage, and low mineral water supplies, and supplementation becomes necessary. Salt is then used to compensate for what the land no longer provides. This is why many horses appear drawn to salt blocks. They are not necessarily mimicking wild behaviour, they are responding to imbalance (Schryver et al., 2025).

The hidden cost of monoculture grass swards

Uniform grassland does more than limit mineral intake. It removes choice.

Most horses are thought to be able to naturally self-regulate by grazing a variety of plants to balance nutrients. In a monoculture of one or two grass species, that ability disappears, and nutritional gaps appear (Dumont et al., 2006).

High-sugar grasses, such as perennial ryegrass, trigger insulin spikes. Elevated insulin causes the body to lose key minerals, particularly sodium and magnesium, through urine. As these minerals deplete, horses experience increased thirst and begin licking salt, often excessively. The cycle doesn’t stop there.

Adding a salt block like the one pictured above can help if salt is needed in the horses diet, but alone, it will not prevent minerla imbalances

Mineral depletion drives appetite and cravings, so horses eat more, usually from the same high-sugar sward. More sugar leads to more insulin, more mineral loss, and more thirst. Over time, this vicious circle increases the risk of weight gain, metabolic stress, and laminitis, particularly in easy keepers, native breeds, and horses prone to sugar-sensitive conditions.

Providing extra salt alone does not break this cycle. The root cause is the uniform, sugar-rich pasture. Diversifying swards with low-sugar grasses, herbs, and wildflowers restores choice, supports mineral balance, stabilises energy, and lets horses self-regulate naturally, just like wild and feral horses do when they forage a variety of plants and lick mineral-rich rocks (Moinardeau et al., 2025).

What happens when pasture diversity increases

Introducing a wider range of safe grasses, wildflowers, herbs, and forbs changes how horses interact with their environment.

Diverse swards provide small but meaningful amounts of sodium and trace minerals. More importantly, they supply the minerals that support absorption and retention, reducing losses rather than constantly trying to replace them (Scasta et al., 2016).

Deep rooted plants access nutrients beyond the reach of ryegrass. Forbs and herbs support gut health, improving mineral uptake. Structural diversity slows intake, stabilises insulin responses, and reduces the metabolic demand for supplementation (Moinardeau et al., 2025).

Species diverse swards are more likely to support horses with a balanced diet.

Horses grazing diverse pasture often show calmer salt consumption. They still use salt when needed, particularly during work or heat, but the urgency reduces. The land begins to share the nutritional workload. Note that some horses, particularly those with metabolic issues will still need careful management.

Learning from wild systems without copying them

We are not trying to turn horse paddocks into wilderness, nor remove salt provision altogether. Wild systems offer principles, not templates.

The principle is this: when land functions as an ecosystem, horses require fewer inputs (Scasta et al., 2016).

Salt supplementation remains good practice in domestic management, especially for working horses. But it works best when paired with land that supports mineral balance rather than undermines it. Monoculture grass creates dependence. Diverse pasture creates resilience (Moinardeau et al., 2025).

By restoring plant diversity through thoughtful seed selection, soil care, and grazing management, we move closer to a system where horses can regulate themselves more effectively, costs reduce over time, and land becomes healthier rather than harder to manage. Healthy soil grows diverse plants. Diverse plants support balanced nutrition. Balanced nutrition supports horse welfare.

That is not a trend. It is how horses evolved to live.

References

1. Schryver, H., et al. (2025). Effect of form on equine salt intake. Journal of Equine Veterinary Science. https://www.sciencedirect.com/science/article/pii/S0737080625001601

2. Clegg, F. M., & McBride, B. W. (1987). Voluntary salt consumption in horses. PubMed.https://pubmed.ncbi.nlm.nih.gov/3568683/

3. Tankersley, R., et al. (2004). Importance of natural mineral licks to ungulates. Alaska Department of Fish & Game. https://www.adfg.alaska.gov/static/home/library/pdfs/wildlife/research_pdfs/importance_natural_mineral_licks_ungulates.pdf

4. Journal of Mammalogy (2008). Field studies of ungulates’ use of mineral licks. https://academic.oup.com/jmammal/article/89/4/1041/867975

5. Scasta, J. D., et al. (2016). Wild and feral horse foraging ecology and nutrient intake. https://www.sciencedirect.com/science/article/abs/pii/S1550742416000038

6. Muskwa-Kechika Research (2004). Mineral access from soil and plant sources in wild herbivores. https://muskwa-kechika.com/uploads/_research_unbc/Mineral_Licks_report_July_2004.pdf

7. NRC (2007). Nutrient Requirements of Horses, 6th Revised Edition. National Academies Press. https://www.nap.edu/catalog/11653/nutrient-requirements-of-horses-sixth-revised-edition

8. Dumont, B., et al. (2006). How do horses graze pastures and affect the diversity of grassland ecosystems? ResearchGate. https://www.researchgate.net/profile/Bertrand-Dumont/publication/258243497_How_do_horses_graze_pastures_and_affect_the_diversity_of_grassland_ecosystems/links/603e4aa04585154e8c70a3fe/How-do-horses-graze-pastures-and-affect-the-diversity-of-grassland-ecosystems.pdf

9. Frank, N., et al. (2010). Effects of high-sugar grasses on mineral loss and insulin response in horses. PubMed. https://pubmed.ncbi.nlm.nih.gov/20612980/

10. Moinardeau, M., et al. (2025). Pasture diversity and its effects on equine mineral intake and metabolic health. Animals (Basel), 15(6), 862. https://www.mdpi.com/2076-2615/15/6/862