solution. Dr. Sara Via, professor at the University of Maryland, has written about this breakthrough research in her publication,“ Increasing Soil Health and Sequestering Carbon in Agricultural Soils.” In it she says:“ The Earth’ s soil can store over twice the amount of carbon dioxide found in the atmosphere. Yet in just 150 years, agricultural soils worldwide have lost a large fraction of this sequestered carbon as a result of agricultural practices that leave soil unprotected.”
Unprotected soil is plowed ground with no crop growing. Unprotected soil has been tilled to kill weeds and prepare for planting, but in the process a superabundance of oxygen has been introduced into the soil and soil aggregates have been shattered, leading to a feeding frenzy by soil bacteria that release carbon-dioxide into the air as they consume soil organic matter. The level of organic matter in the soil drops, the structure of the soil suffers, and the added carbon-dioxide in the atmosphere contributes to climate change.
Montgomery County farmers are embracing farming practices that can reverse the climate impacts of agriculture. No-till planting reduces the inverting and pulverizing of the soil structure. Cover crops restore organic matter in the soil, supporting a microbiological community in the soil that balances bacteria and fungi. Spreading animal manure and compost on crop fields is a direct application of organic matter to topsoil.
Farmers are beginning to apply biochar, a valuable soil amendment produced from agricultural residues. It can improve soil structure, reduce water use, and support a flourishing community of soil microbiology. Because biochar persists in agricultural soils for a long time, adding it sequesters atmospheric carbon-dioxide for centuries or longer.
Every farmer sends off samples of soil from each field to a soil testing lab where samples are analyzed to determine the concentration of a dozen or more soil components. Every test report includes the percentage of organic matter in the soil sample. And from the complexity of the soil test report, one crucial formula emerges: a higher concentration of soil organic matter means more carbon stored in the soil which means less carbon dioxide in the atmosphere. That’ s climate mitigation!
Good farmers scan their soil test results, hoping to see soil organic matter concentrations rising. More organic matter in soil means improved soil texture, improved water-holding capacity of the soil, creating
Top: The farmworker team spreading compost— our primary source of fertility, along with cover-crop residues; above; loading the spreader with biochar.
a measure of drought resilience, and, as soil organic matter breaks down gradually, it releases plant-available nutrients to the crop. Up to a point, it is in the farmer’ s interest to make the investments needed to increase soil organic matter.
Beyond that point, agricultural soils could play a much greater role in our global response to the climate crisis. Farmers may hate to hear me say it, and in the current political climate the possibility seems remote, but in my view it is the role of governments to build into the business of farming the incentives to get more carbon stored in the Earth’ s soil. Let’ s have the win-win of a future that combines a stable climate and an abundant global food supply.
Tom Farquhar grows vegetables at Sandy Spring Gardens in Eastern Montgomery County. After a career in teaching and educational leadership, Tom returned home to Sandy Spring to grow fresh food, first for local distribution at farmers markets and through CSA subscriptions, but now focussing primarily on Montgomery County food assistance through Community FarmShare, Manna Food Center, and other charity food programs.
8 plenty I spring sowing 2026