Conservation Agriculture

By David O’Neil

Could a single idea embraced globally make a major contribution toward avoiding catastrophic climate change, while at the same time increasing the world’s food supply, restoring biodiversity and, in fact, saving farmers money?  “Conservation Agriculture” is that rapidly evolving practice.  American soils have lost more than 40% of their carbon since colonial times, first from plowing, then from chemical additives that have killed off the microscopic life of the soil. Escalating in use after World War II, it became known as “agrochemical farming,” and “the Green Revolution.”  But now, through the practice of Conservation Agriculture, very large quantities of carbon can be removed from the atmosphere and RE-sequestered over time in the soil. 

The principles of Conservation Agriculture are all in practice in Lincoln today.  Codman Farm, now managed by Pete Lowy, was formerly reliant on hay production; it is now rebuilding soil organic matter by returning animals to the pastures to increase forage fertility through the use of directly deposited animal manures. Properly managed rotational grazing of chickens, cows, pigs and turkeys assures a proper level of animal impact to the soil and an even distribution of manure.  Take a look at Mt. Misery field.

Drumlin Farm is also rebuilding soil carbon, through the basic organic principles – no chemical pesticides, herbicides, or fertilizers – and through the practice of “fallowing,” where each acre produces crops for five years and then “rests” for two years.  During that time the land is never bare, but cover-cropped with clover in order to fix nitrogen and build organic matter.  With the help of its farm animals, Drumlin Farm also produces its own compost, which is entirely recycled to its fields.  Farm Manager Matt Celona says that because of the level of soil organic matter it has achieved through these practices, irrigation is never required.

Lindentree Farm is experimenting with reduced tillage – plowing (or tillage) exposes and oxidizes sequestered carbon, turning it into carbon dioxide.  Plowing also reduces organic matter and the micro-organisms that healthy soils depend on.  One technique that Farm Manager Ari Kurtz is using is called “occultation” – a series of large black tarps are spread over prepared soils and weighted down for a period of several weeks in the spring or summer.  The weed seeds underneath germinate but then die due to lack of light.  A subsequent crop can then be planted that grows in a relatively weed-free environment, requiring less cultivation and soil disturbance.  The farm is also trying new combinations of cover crops to add soil organic matter.

Not least, Lincoln’s Agricultural Subcommittee (which works with the Agricultural Commission) has steadfastly promoted ALL of the principles of Conservation Agriculture in their leased land: they encourage organic practice, diverse crop rotations, minimal soil disturbance (no-till), and the steady use of cover crops.

FPL Green strongly encourages all of us to fight climate change by supporting Lincoln’s farms and their actions to implement Conservation Agriculture.  Buying food locally will not only help mitigate climate change but has the added benefits of improving the health of our ecosystems and our economy.