No-till Farming and the Environment: Do No-Till Systems Require More Chemicals?

The sustainability of agricultural production is regaining importance, particularly in view of the predicted population increase. Terms such as “sustainable production intensification” are widely discussed within the global development agenda. In the area of agricultural crop production one term – no-till – is leading to increased polemic and polarization of the parties. No-till or no-tillage describes a form of cropping which does not use mechanical tillage of the soil for crop establishment. Mechanical tillage, a standard operation in agriculture since ancient times, is mostly symbolized by the use of the plough. Where ever it has been practiced, it has led to soil degradation and erosion and is considered as the root cause for severe and large scale signs of landscape degradation or even desertification. One of the most spectacular soil erosion events caused by soil tillage was the famous dust bowl in the United States of America in the 1930s, but soil erosion problems are still observed around the globe. David Montgomery in his book Dirt – the erosion of civilizations describes how, in most parts of the world, soil tillage has led to soil erosion in quantities that exceed the natural soil formation by orders of magnitude. In human history, the decline of major civilizations can be attributed to erosion events, i.e. to a loss of productive capacity of the soil. Hence, soil tillage can no longer be considered to be compatible with sustainable agriculture and therefore the possible solution to address the threat of unsustainability of the agricultural soil resource base would include the avoidance of mechanical soil disturbance, or no-till. Those who oppose this notion argue that no-till is equated with an abusively high use of herbicides and even genetically modified organisms (GMOs) are synonymous with unsustainable agriculture, with no-till taking all the blame. Unfortunately, both sides are right, and therefore, to get closer to the answer of the initial question, we have to take a deeper look into no-tillage systems, to find out, whether no-tillage is really the problem, or whether there are other associated problems which are falsely blamed on no-till?