Carbon management firm Carbon Direct has published Sustainable Agricultural Biomass Sourcing for CDR: A Buyer’s Guide, establishing one of the first globally applicable frameworks for sourcing agricultural residues as feedstocks for carbon dioxide removal (CDR) projects.
Developed in collaboration with climate scientists, industry stakeholders, and corporate backing from major carbon removal buyers including Microsoft and Stripe, the guide establishes concrete criteria for project due diligence and offtake agreement negotiations. The framework aims to standardize purchasing practices while formal certification bodies and regulatory frameworks catch up with the fast-growing market.
Biomass-based carbon removal pathways—such as biochar and bioenergy with carbon capture and storage (BECCS)—have expanded rapidly, accounting for more than 95 per cent of high-durability CDR volumes contracted globally in 2025. As multinational corporations scale up their climate commitments into multi-million-tonne offtake agreements, the environmental and social provenance of the underlying biomass has faced intense scrutiny.
While agricultural residues like corn stover, wheat straw, and rice husks are attractive feedstocks because they are by-products of existing food systems, these materials often play critical secondary roles in local economies and ecosystems. Diverting them without structural safeguards introduces substantial reputational, ecological, and regulatory risks for both project developers and corporate buyers.
To mitigate these risks across varying international jurisdictions, the framework outlines four core principles for responsible agricultural biomass procurement:
- Traceability: Mandating that all biomass volumes be fully traceable back to their geographic point of origin, utilizing three distinct chain-of-custody tracking models adapted to specific supply-chain complexities to prevent double-counting.
- Community and worker protection: Ensuring feedstocks are sourced exclusively from regions and operations with a low risk of negative impacts on local populations, agricultural workers, vulnerable demographics, and Indigenous Peoples.
- Soil and environmental protection: Dictating that residue harvesting practices minimize the degradation of soil health, soil quality, and existing topsoil carbon stocks, while strictly prohibiting extraction from ecologically protected conservation zones.
- Market integrity: Verifying that the commercial diversion of agricultural by-products does not artificially distort local markets for food, fodder, forestry, or alternative agricultural commodities.
The guidance is structured to account for geographical variations in land tenure systems, data availability, governance capacity, and regional corruption risks. Carbon Direct intends to maintain the guide as a living document, updating future editions to reflect shifting agronomic science and voluntary carbon market dynamics. The publication builds upon Carbon Direct’s previous forest biomass sourcing guidelines published over the last two years, as well as its ongoing collaborative work authoring Microsoft’s High-Quality Carbon Dioxide Removal criteria.
Dr Bodie Cabiyo, Director of Interdisciplinary Science at Carbon Direct, emphasized the multi-dimensional risks of poor procurement, stating: “Agricultural residues exist at the intersection of food systems, land tenure, livelihoods, and carbon accounting, so poor sourcing doesn’t only undermine carbon credits, it can cause real ecological and community harm. This guide gives developers the confidence that responsible sourcing decisions made today will hold up over time and gives buyers clear lines to draw in their contracts.”
Phillip Goodman, Director of Carbon Removal Portfolio at Microsoft, highlighted the infrastructure value of the framework, noting: “Rigorous science and clear standards are the foundation of a trustworthy carbon removal market, and this guide delivers exactly that. By setting a high bar for sustainable agricultural residue sourcing, we are supporting infrastructure for CDR growth that translates into material climate benefit.”
Dr Zeke Hausfather, Climate Research Lead at Stripe, added: “Getting biomass sourcing right is table stakes for scaling CDR credibly. The science and the market will keep evolving, but this guide gives buyers and developers a strong starting point, which is what the market needs right now.”
