Soil compaction is quietly limiting pasture productivity and affecting horse health. Thanks to the work of 2022 Nuffield Scholar Adam Williamson, the thoroughbred industry now has practical, evidence-based strategies to address it.
Every step a horse takes puts pressure on the soil, up to 87 psi (pounds per square inch) when galloping. Over time, this creates compacted layers that restrict root growth, water infiltration and microbial activity. Unlike cattle farms, horse properties often can't rotate paddocks as freely due to social behaviours and lower stocking densities. That means the same areas are grazed continuously, giving soil little chance to recover.
At Vinery Stud in the Hunter Valley, where Adam manages operations, compaction is the biggest barrier to pasture performance. Drawing on his 16 years across beef, irrigation and stud farming, he saw an opportunity to apply soil health principles from other industries to the equine world.
As part of the Nuffield Scholarship sponsored by AgriFutures Australia, Adam travelled to six countries to explore how others manage similar challenges. In Zimbabwe, he saw how simple tools were being used to establish pasture in water drains. In Israel, he learned how drip irrigation could reduce both water use and compaction. These insights helped shape practical solutions tailored to Australian conditions.
Healthier soil, healthier horses
Adam's research shows that compacted soils don't just affect pasture, they can impact horse wellbeing too. Poor soil health can lead to less diverse and nutritious feed, harder ground surfaces, and even behavioural issues. His findings echo racetrack studies linking surface firmness to injuries and diseases like laminitis and tendonitis.
But there's good news. There are many approaches to enhance pasture growth, combatting compaction effects. Trials have suggested targeted applications of foliar mixes including strategic plant hormone treatments can increase pasture growth by up to 55% in just 3 weeks. Managing plant hormones also helps smooth out seasonal feed gaps, supporting more consistent nutrition.
Modern tools like NDVI (Normalized Difference Vegetation Index) mapping and EM38 soil scanning helped Adam pinpoint problem areas and track improvements. He also explored soil microbiome testing, revealing how compaction disrupts the ideal balance of fungi and bacteria needed for healthy nutrient cycling.
These tools give farm managers real data to guide decisions, moving beyond guesswork to targeted, effective action.
Practical steps for stud farms
Adam's recommendations are grounded in what works on the ground. Key strategies include:
• Strategic deep ripping to break up subsoil compaction.
• Sacrifice areas and night yards to protect high-value pasture during wet periods.
• Mobile dairies and irrigation units, inspired by Zimbabwean systems, provide flexibility and ease pressure on paddocks.
He's clear that solutions need to be adapted for the realities of horse farming.
Better soil management doesn't just help horses, it's good for the planet and the bottom line. Reducing compaction can cut nitrous oxide emissions and phosphorus runoff, while also lowering reliance on costly supplementary feed.
For an industry where feed is a major expense, these changes can deliver real savings alongside improved animal welfare.
Investing in ideas that matter
AgriFutures support for Adam's Nuffield Scholarship reflects a broader commitment to practical, forward-thinking research. The Nuffield program has helped more than 500 Australians explore global solutions to local challenges and Adam's work is a standout example.
His research offers the thoroughbred industry its first comprehensive framework for tackling compaction. But the benefits don't stop there. Other livestock sectors, like bull breeding, could also apply these insights.
