Oxford Report: Fashion’s Fiber Sourcing Could Influence About 30% Of Global Agricultural Land

A new analysis from the University of Oxford’s Smith School of Enterprise and the Environment, produced in partnership with the Dirt charity, estimates that the sourcing of five natural-fiber categories overlaps with roughly 1.45 billion hectares — about 30.15% — of the world’s agricultural land. The authors stress this figure represents potential influence through sourcing and purchasing decisions, not that fashion occupies or is solely responsible for one-third of global farmland.

How the Estimate Was Calculated

The report groups five fiber categories (leather, wool, cotton, linen/hemp and silk) and counts the full agricultural footprint associated with each. That means it attributes the total land area supporting a fiber — even where that same land also produces food or other commodities — to approximate the territory over which the textile sector could exert influence.

Key area estimates in the report include: leather linked to about 876 million hectares of grazing land; wool associated with roughly 528.4 million hectares; cotton occupying 34.7 million hectares; linen and hemp combined at 5.9 million hectares; and silk at 2.3 million hectares. Leather and wool together account for nearly 97% of the total footprint identified.

Power, Not Blame

"We are not measuring blame. We are measuring power, and it turns out fashion has far more of it than anyone has been telling us," said Arizona Muse, founder of Dirt and a co-author of the report.

The authors argue that brands’ sourcing requirements can change how fields are farmed — for example, farmers do not typically separate pesticide or soil-management practices between cotton lint and seed, so rules covering textile-grade cotton can affect whole fields and associated outputs.

Allocation Complexities: Leather, Wool And Shared Systems

Leather and wool raise allocation challenges because the land that supports them also serves the meat and dairy industries. The report does not split acreage between those uses, noting the leather sector has not consistently decided whether hides should be treated as by-products or co-products of livestock agriculture. The authors also flagged ambiguities in FAO data about whether sheep could be counted in both leather and wool statistics and assumed those figures largely represent different animals or breed types used for distinct purposes.

As context, the report notes that more than 2.9 billion square metres of genuine leather were processed worldwide in 2024, of which about 1.2 billion square metres were used by footwear, handbags and apparel; the rest served furniture, automotive and other industries.

Environmental Impact Varies Widely Within Materials

A major takeaway is that production methods and sourcing choices can produce greater environmental differences within a single material than the average difference between two different materials. For example, life-cycle assessments reviewed in the report place leather’s global-warming impact between 8.5 and 151.9 kg CO2e per m². By comparison, one mycelium-based leather alternative registered 2.76 kg CO2e per m², while another produced using a coal-heavy power grid reached 57.15 kg CO2e per m².

Viscose estimates also varied substantially — from 0.20 to 8.30 metric tons CO2e per metric ton of fiber — reflecting differences in feedstock, production systems and energy supply. The report cautions these figures are drawn from separate studies with different boundaries and methods and are not uniform comparisons conducted by the Oxford team.

Uncertainties And Methodological Notes

The authors acknowledge several uncertainties: the wool calculation relies on a single available estimate from the animal-advocacy group Circumfauna that producing one metric ton requires 250 hectares, and FAO data do not make it fully clear whether individual animals might be counted across multiple categories. Even excluding wool, the other fiber categories would still touch roughly 19% of global agricultural land under the report’s method, with leather alone representing about 18.25%.

Farming Systems, Trials And Recommendations

The report’s second half reviews organic, regenerative and biodynamic systems, finding evidence that organic and biodynamic practices can support higher species richness and improve some soil-health metrics compared with conventional agriculture. Case studies highlighted include a five-year Sekem trial in Egypt where pesticide use dropped to under 10% of prior levels, cotton yields rose nearly 30%, and soil salinity declined 18%, and 12-year cotton-rotation trials in India reporting healthier soils and stronger microbial communities under biodynamic management.

However, the authors note the scientific evidence specific to biodynamic preparations is still tentative and incomplete. They call for standardized methodologies, longer-term studies, and more research into commercial viability, certification costs and land-use trade-offs.

Policy And Standards

Dirt initiated and partly funded the research; Muse and Dirt strategy director Heleen Petzer are among the report’s five co-authors. The charity is developing a Demeter Textile Standard with Biodynamic Federation Demeter International that would cover 11 raw-material categories and extend from agricultural production through processing and manufacturing, with requirements on soil health, biodiversity, animal welfare, working conditions and garment compostability.

The report was published shortly before EU member states were set to begin applying the Empowering Consumers for the Green Transition Directive on Sept. 27. On the headline figure, Muse said: "Our confidence is in the scale, not the second decimal point. The report calls itself a preliminary framework for further inquiry, not a final analysis, and the headline is approximately 30 percent."

What This Means For Brands

The central message is practical: by changing sourcing policies and purchasing decisions, fashion and textile brands have a meaningful opportunity to influence land use and environmental outcomes across supply chains — especially where a relatively small number of large commodity footprints (leather and wool) dominate the area exposed to influence.