Carbon Sponge Hub at White Feather Farm
A Four-Year Journey in Soil Carbon Stewardship (2021-2025)
From 2021 to 2025, White Feather Farm served as headquarters for the Carbon Sponge Hub, an interdisciplinary collaboration bringing together farmers, scientists, artists, and educators to better understand soil carbon sequestration as a climate solution while improving soil and human health.
Led by Carbon Sponge founder Brooke Singer, this initiative established a network of small-scale farms across the Hudson Valley and Catskills. Through experimental plots, simple field monitoring tools, and professional laboratory testing, Hub members collected data and refined cultivation techniques—considering both cutting-edge science and ancient land-use traditions.
Originally initiated at the New York Hall of Science in 2018, Carbon Sponge partnered with White Feather Farm in 2021, establishing the Hub headquarters here in 2024. The project was supported by grants from Northeast SARE and The Spark of Hudson.
The Focus: Climate-Smart Sorghum
The Hub focused on white-seeded annual grain sorghum—an underutilized crop with tremendous potential. Originally from East Africa, sorghum is naturally drought-tolerant, deep-rooted, and accumulates silica that binds with carbon. For five years, we grew multiple varieties without irrigation or chemicals, saving seed year to year and adapting plants to our bioregion.
Carbon Sponge harvested both grain and stalk juice (which evaporates into a molasses-like syrup), making sorghum a valuable dual-purpose crop. The question driving the work: Can we create food systems that simultaneously feed the soil and our bodies?
Why White Feather Farm
White Feather Farm provided the ideal foundation for this work:
Living Laboratory: From 2021-2024, Carbon Sponge maintained an experimental plot (16 by 50 feet) deliberately selected for its challenging conditions: compacted silt soil with poor drainage. With no amendments beyond initial compost in 2021, we demonstrated how much improvement could be achieved through plants and minimal cultivation alone, tracking changes over four seasons through winter cover cropping and biomass incorporation.
Hub Headquarters & Network Support: Farmers Celia Fay Brubaker and Jonathan Friedmann provided essential operational support, greenhouse facilities for seedling starts, and coordination for the growing network of participating farms.
Public Education Platform: Annual Soil Fest events and on-farm workshops made cutting-edge research accessible to the wider community.
Scientific Collaboration Site: The farm hosted professional research activities including soil profiling and served as a gathering point for visiting scientists, advisors, and partner farms.
Key Events at White Feather Farm
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A landmark two-day soil profile event brought together leading soil scientists:
Dr. Peter Groffman (CUNY Graduate Center's Advanced Scientific Research Center and Cary Institute of Ecosystem Studies)
Dr. Sara Perl Egendorf (Pace University)
Dr. Claudio Colombo (Università del Molise, Italy)
Rich Shaw (retired USDA-NRCS Soil Scientist)
Olga Vargas (USDA-NRCS Soil Scientist)
We dug three soil pits across the farm, conducting comprehensive surveys of physical, chemical, and mineralogical properties as well as carbon stock assessments. These baseline surveys continue to guide best management practices at the site and provided crucial data for ongoing research.
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In 2022, White Feather Farm collaborated with Carbon Sponge to produce this 15-minute film documenting the project's philosophy and practices.
Narrated by Brooke Singer | Filmed by Jess Giacobbe | Illustrated by Corey Cavagnolo | Animated by Brandon Vassallo | Music by Steve Spinella | Produced and Created by White Feather Farm
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From 2022-2024, Brooke Singer hosted public Carbon Sponge Workshops at White Feather Farm's annual Soil Fest, where attendees explored strategies for keeping carbon in the soil for the benefit of microbes, plants, people, and climate.
In 2023 and 2024, Brooke introduced a meditative component, guiding participants to tap into the network of living and non-living elements that constitute "agroecology." Workshop attendees learned to design their own carbon sponge systems and gained hands-on experience testing soil with the Carbon Sponge Kit.
Major Outcomes
Measurable Impact
The 2024 study revealed significant soil health improvements, with one partner farm experiencing nearly 2% increase in organic matter in just one year through residue retention and reduced soil disturbance—clear evidence that regenerative practices build soil carbon.
Accessible Monitoring Tools
We validated a suite of affordable field tools that farmers can use to track soil health in real-time, making evidence-based decision-making accessible to small-scale operations.
Successful Scaling
Through trial and innovation, we scaled sorghum production from market garden beds to 2-acre plots, harvesting approximately 40 pounds of grain and 100+ gallons of juice at partner farms while developing mechanical methods suitable for small farm operations.
Peer-to-Peer Learning
The Hub demonstrated the power of farmer networks. Through regular field visits, midseason check-ins with technical advisors, and collaborative problem-solving, farmers reduced risk while experimenting with climate-smart crops.
Hub Network Evolution
2021: Carbon Sponge established partnership with White Feather Farm
2022: First Hub year with 5 participating farms
2023: Network expanded to 10 farms across the Hudson Valley and Catskills
2024: Refined network of 5 farms conducting intensive study (White Feather Farm, Sweet Freedom Farm, Nimble Roots Farm, Foxtrot Farm & Flowers, and Home Farm/Coming Home Seeds)
2025: Continued monitoring of Sorghum fields and hub activities
Legacy & Impact
The Carbon Sponge Hub at White Feather Farm demonstrated that small farms can be sites of serious scientific research, that accessible tools empower evidence-based decisions, and that climate-smart crops like sorghum have tremendous potential in the Northeast. Through interdisciplinary collaboration, we showed that ancient crops hold solutions to modern challenges.
In 2025, Carbon Sponge relocated its headquarters to Wally Farms in Ancram, NY, carrying forward the lessons learned and relationships built during four transformative years at White Feather Farm.
Acknowledgments
Carbon Sponge Team: Brooke Singer (Founder), Nathan Pollack and Anne-Laure White (Field Assistants), Dr. Sara Perl Egendorf (Pace University), Nate Kleinman (Experimental Farm Network)
White Feather Farm: Celia Fay Brubaker (Farm Manager), Jonathan Friedmann (Greenhouse Manager), Dr. Marcos Stafne (Executive Director) Jess Giacobbe (Communications Manager/Photographer)
Scientific Partners: Dr. Peter Groffman (CUNY/Cary Institute), Dr. Claudio Colombo (Università del Molise), Rich Shaw & Olga Vargas (USDA-NRCS)
Funding: Northeast SARE, The Spark of Hudson
Participating Hub Farms (2021-2024): Sweet Freedom Farm (Germantown), Nimble Roots Farm (Catskill), Foxtrot Farm & Flowers (Stanfordville), Home Farm/Coming Home Seeds (Clermont), Bonhomie (Athens), The Lo Farm (Catskill), Mossy Stone Farm (Prattsville), Newton Farm (West Kill), Stone Berry Farm (Athens), Zena Farmstead (Woodstock).
Resources
Learn More: https://carbonsponge.org/
Supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, through the Northeast Sustainable Agriculture Research and Education program.