Summary of Counter-Arguments:
| - Studies have shown that organic farming can build soil organic matter better than conventional no-till farming. - No-till is not sustainable if it relies on herbicides because they are very toxic to the environment and to people’s health. - There is a large, untapped potential for organic no-till methods. |
Details of Counter-Arguments:
Organic farmers are very concerned about protecting and enhancing soil fertility. Organic agricultural practices are designed to work with and emulate living ecological systems and disturb the natural balance as little as possible. As a result of this focus, organic farmers, since early times (even before the no-till approach started to take roots among conventional farmers), have been interested in reduced-tillage methods. However, the negative impact of tilling is much less of an issue in organic farming than it is in conventional farming. Ploughing encourages erosion mainly if the soil remains uncovered for a long period of time and if its organic matter content is low, which decreases its structural stability. Through techniques such as mulching, planting cover crops, and intercropping, organic farmers often succeed in maintaining a soil cover throughout most of the year. In addition, the higher organic content of soils on organic farms (due to use of compost, manure, mulch, and other organic fertilizing inputs) helps limit soil degradation and erosion. The secondary tillage operations performed for weed control typically have a low disturbance on the vertical structure of the soil as they “break” and “cut” rather than turn the soil. Organic agriculture farming practices are widely known for their positive effect on soil organic matter, soil organisms, and soil physical structure, and can achieve this result without the use of herbicides, which pollute both the soil and the water. On the contrary, conventional no-till farming may reduce soil erosion compared to tillage-intensive conventional farming, but is often combined with the application of huge quantities of herbicides that are very toxic to the environment and people’s health. Research conducted over a nine-year period by the US Department of Agriculture’s Agricultural Research Service has shown that organic farming can build soil organic matter better than conventional no-till farming. The research showed that organic farming’s addition of organic matter in manure and cover crops more than offset losses from tilling. [1]
Moreover, sustained reduced tillage or no-till farming are not incompatible with organic farming. There are many very promising examples, both on farms and at research stations, that show that zero-ploughing and even no-till organic farming are possible and productive. In the United States, the Rodale Institute is running a promising research project on no-till organic farming (the No-Till + Project), and has developed a cover-crop roller designed to achieve cover-crop mechanical kill without disturbing soil structure. [2] Similar and lower-tech (even animal-drawn) implements exist now in many countries, including developing countries. There are many organic farmers who have been successfully running no-till systems for years in the US. In Japan, Fukuoka’s farm has been operating an organic no-till system for many decades. [3] In France, Joseph Pousset successfully experimented with zero-ploughing and zero-input organic agriculture for more than 13 years. [4] In southern Brazil, there are many examples of successful no-till, organic farming systems, and the introduction of no-till, no-herbicide practices has enabled a net gain of over US$100/ha. [5]
In fact, Organic Agriculture has the potential to be even more successful using no-till methods because the secret to achieving effective no-till is applying massive amounts of organic matter to the soil (especially green manure and cover crops). [6] No-till systems are particularly sustainable when they rely on cover crops (instead of herbicides) to control weeds in between cropping seasons, which is a practice particularly suitable to Organic Agriculture. Furthermore, these cover crops often also fix nitrogen into the soil which reduces the need for synthetic fertilizers. Other methods can also be combined to control weeds (alone or in conjunction with cover crops), such as crop diversification or grazing livestock. All these organic methods build soil fertility and render tillage less and less necessary as the soil structure improves, whereas merely applying round-up before sowing (as is done most of the time in conventional no-till) does not do any good to the soil.
In summary, organic farming systems, as currently employed, build healthy soil and limit erosion. That said, organic agriculture would benefit if no-till or low-till technologies were to be widely adopted. Advances in this area are now much further along than many critics acknowledge. [7] Organic, no-till farming is not easy, but is promising. The difficulty lies in that farmers need a good understanding of the soil ecosystem in order to be successful and building this knowledge base is more time-consuming than purchasing and spraying herbicides. However, the success of no-till methods in organic farming is much more rewarding, less costly, and definitely more sustainable than in conventional agriculture. As a US weed ecologist said: “You ought to be paying yourself for being a good manager rather than paying someone else to supply you with inputs." [8] 1] Read more in the July 2007 issue of Agricultural Research magazine (www.ars.usda.gov/is/pr/2007/070710.htm)
[2] See the Internet plateform for no-till + of the Rodale Institute at http://www.newfarm.org/depts/notill/index.shtml
[3] Fukuoka’s approach is explained in his famous book “One Straw Revolution” (1978)
[4] See one of Pousset’s books: “Engrais verts et fertilité des sols” for more information.
[5] Result of the AS-PTA (Assistance and Service for Alternative Agriculture Projects) program.
[6] See the impressive experience of Roland Bunch (World Neighbors) in Honduras and many other countries on this topic at http://www.newfarm.org/features/1002/roland_bunch/index.shtml
[7] The reader may want to consult the book “Pursuing Conservation Tillage Systems for Organic Crop Production” by George Kuepper, 2001, available online at http://attra.ncat.org/attra-pub/organicmatters
/conservationtillage.html#tillage
[8] Dr. Adam Davis, quoted in an article from The New Farm on http://www.newfarm.org/depts/notill/
features/2005/0602/msuroller.shtml