A sweeping international study confirms what many farmers have long suspected: diverse pastures are more productive and resilient than monoculture grasslands. Researchers from 26 sites across four continents found that mixing grasses, legumes, and herbs not only reduces the need for synthetic fertilizers but also boosts yields and improves overall soil health. The findings, published in Science, represent a potential turning point in agricultural practices as farms worldwide grapple with the challenges of climate change and sustainable food production.
A global study involving researchers from 26 locations across four continents confirms that diverse pastures – those incorporating grasses, legumes, and herbs – demonstrate improved yields and enhanced soil health. This finding could reshape agricultural practices, offering a path toward more sustainable and resilient farming systems.
- More plants, less fertilizer.
- More vibrant soils.
- Stable, and often increased, yields.
- Reduced nitrogen loss.
- More nutritious forage.
- Increased resilience to heat.
- More stable farms; lower costs.
- A viable pathway to low-emission agriculture.
Mixed Pastures: More Food with Less Fertilizer
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Pastures underpin vast livestock regions worldwide. For decades, many farms have relied heavily on single grass species and high doses of synthetic nitrogen to maintain production. While this system can work, it often leads to soil degradation, water contamination, and rising emissions.
Increasingly, farmers are seeking methods to protect land without sacrificing the productivity needed to feed livestock.
A broad group of international scientists has now tested a long-held ecological idea, but one that hasn’t been widely explored at scale: a pasture with more species can produce more forage while requiring significantly less nitrogen input.
The initial hypothesis showed promise, and new global research now provides compelling evidence.
A Long-Standing Agricultural Puzzle
Farmers working with pastures face a difficult balancing act: high yields without soil deterioration. Traditional models, based on monocultures and intensive fertilization, simplify daily management but create underlying problems.
Nutrients are lost through leaching, soil compacts, biodiversity declines, and increasingly extreme weather exacerbates the issues.
A shift towards more diverse plant mixes offers a potential solution. Recent studies consistently show benefits when grasses, legumes, and herbs share the same field: increased biomass, reduced fertilizer use, deeper roots, and more efficient nutrient cycles.
Diversity is proving to be more than just an ecological benefit; it’s becoming a key agronomic tool.
A Global Investigation for a Global Challenge
The international consortium LegacyNet conducted a coordinated experiment at 26 sites across Europe, North America, Asia, and New Zealand. Each region tested three types of pasture:
- A system with a single species.
- A system with one grass and one legume.
- A system of six species, combining two grasses, two legumes, and two herbs.
The results were clear: diverse mixes maintained high yields with minimal nitrogen input, while monocultures required much larger doses to achieve comparable results.
Each location utilized species adapted to the local climate – perennial ryegrass, fescue, red clover, white clover, chicory, plantain – allowing researchers to evaluate dynamics in real-world and highly variable conditions.
Why Diversity Works
The six-species pastures outperformed many conventional pastures that received significantly more fertilizer. The key isn’t a single “super plant,” but rather the collaborative effect of complementary functions:
- Grasses provide bulk and stability.
- Legumes fix atmospheric nitrogen, reducing reliance on fertilizers.
- Herbs are more resilient to water and heat stress.
The outcome isn’t simply the sum of its parts, but a greater collective performance. One species compensates for the deficiencies of another, leading to more efficient use of light, water, and nutrients. In warmer regions, where climate stress is heightened, the benefits were even more pronounced.
A Scientific Study That Sets a Trend
For the LegacyNet team, this international collaboration represents a paradigm shift. A common experimental design, replicated across so many countries, provides robust conclusions that aren’t dependent on the climate or soil type of a single location.
This approach is gaining traction in other agricultural projects, driven by the need to adapt food systems to the new climate reality without compromising productivity.
Guidance for Livestock Farms
The message is clear: mixed pastures produce more with less nitrogen. Researchers suggest that optimal combinations typically include between one-third and two-thirds legumes, complemented by grasses and herbs that provide structure and resilience. This ratio not only maintains yield but also reduces nutrient loss and improves soil health.
For many farmers, this translates to economic savings, reduced dependence on external inputs, and more stable systems in the face of droughts or extreme heat.
How Diversity Transforms Pastures
What began as local trials in Ireland has evolved into a global effort. The pattern remains consistent across all analyzed continents: diverse pastures generate better animal nutrition, less nitrogen loss, greater stability in rising temperatures, and more cohesive soils.
Deep roots tap into soil niches inaccessible to monocultures. Legumes provide biological nitrogen where it’s needed most. Herbs expand tolerance to drought. And collectively, these systems require less human intervention.
More information: Multispecies grasslands produce more yield from lower nitrogen inputs across a climatic gradient | Science
