Groundwork BioAg announced on June 25, 2026, that through its carbon removal program Rootella Carbon, it issued 19,568 Verified Carbon Units, independently verified by SCS Global under the Verra Verified Carbon Standard. According to Groundwork BioAg, this represents the first issuance under Verra methodology VM0042 in the United States. The program's participating farmland expanded from roughly 9,000 acres in 2023 to over 700,000 acres in the U.S. Midwest and Canadian prairies.
How Fungal Treatment Binds Carbon
Rootella Carbon delivers only removal credits for CO2 actually removed from the atmosphere, not avoidance credits for avoided emissions, according to Groundwork BioAg. The program relies on mycorrhizal fungi that promote formation of mineral-associated organic matter, a carbon pool the company says remains stable over centuries to millennia regardless of management practice. Enrolled farmers receive up to 70 percent of net proceeds from certificate sales.
What VM0042 Verification Means
Standards body Verra released a revised VM0042 methodology in September 2024 for improved agricultural land management, allowing new projects to distinguish between credits from emission reductions and those from carbon dioxide removal. Verra CEO Mandy Rambharos said the methodology enables strict, science-based accounting of agricultural land management. The first issuance for the now over 700,000-acre program demonstrates it functions as intended on the ground. For the 2023 cohort, Groundwork BioAg reports a verified average net effect of 2.23 tonnes of CO2 equivalent per acre, measured across 8,791 treated and eligible acres in the U.S. Midwest and South. Validation and verification were performed by SCS Global Services, a Verra-certified independent verification body.
Where Scientists Express Doubt
A study published in April 2026 in the journal New Phytologist by Tang and colleagues tested various grasses in monoculture, including Leymus chinensis and Stipa grandis, using an ingrowth core method. The presence of arbuscular mycorrhizal fungal hyphae did not change total soil organic carbon stocks, though proportions of readily degradable and stable carbon shifted significantly. The authors concluded that the effect of fungal hyphae depends on the host plant, and changes in plant community composition could strongly influence carbon dynamics in grasslands. Stanford climate scientist Rob Jackson expressed doubt in 2024 whether the effect promised in field trials of fungal additives on managed farms could be statistically detected. CSIRO soil biologist Alan Richardson called the basic principle plausible in the same report but named annual application over many years as a prerequisite, noting whether the principle actually transfers to practice remains unknown. Critics also complained that earlier soil carbon credits were sometimes issued for seasonal weather variations rather than substantive changes, The Japan Times reported in August 2024. In unusually wet years, carbon accumulated that disappeared in dry years.
In Comparison
The principle is already in commercial use in Australia. According to a statement from Loam Bio, the Nicholson Carbon Project in central New South Wales generated 4,867 Australian Carbon Credit Units on 2,177 acres, with each credit representing one metric tonne of CO2 equivalent removed from the atmosphere and stored in soil. The Nicholson family had practiced reduced tillage, more diverse crop rotations, and improved crop residue management for more than a decade before integrating the fungal treatment CarbonBuilder into their operation in 2024. For perspective, the entire global carbon dioxide removal market delivered 2 megatonnes of CO2 equivalent in the previous year, according to Groundwork BioAg CEO Alon Werber, who announced plans to deliver half that total global amount within two years using Rootella Carbon alone. The IPCC mentions a larger figure in a report from OilPrice.com in August 2024: soils could absorb over 5 gigatonnes of carbon dioxide annually, equivalent to one-seventh of human-caused CO2 emissions.
At project level, permanence is embedded in Verra methodology, including a 21 percent buffer pool. Application of the fungal preparation is the only measured change in management practices at most participating farms. Most participating operations also use reduced tillage, allowing mycorrhiza to regenerate across multiple growing seasons. The issuance of first U.S. credits under VM0042 marks the transition from project development to active delivery in the voluntary carbon market, in Groundwork BioAg's assessment.