No-tillage cropping systems were developed for conventional agriculture and usually rely on herbicides and soluble nitrogen fertilizers. The current project aimed at adapting reduced tillage systems to the conditions of organic farming.
Reduced tillage (shallow tillage, loosening or turning until 5 cm depth) has been compared with ploughing (until 15 cm depth) since the start of the project in autumn 2002. This experiment also allows us to test additional factors for the optimization of reduced tillage, i.e. “fertilization with slurry” versus “manure compost” and ”biodynamic preparations” versus “no biodynamic preparations”. It is run on a clayey soil at the FiBL experimental farm in Frick and accompanied by a group of organic farmers and advisors.
In the first three years average yields in reduced tillage were 10% lower than in plough systems, whereas they turned to be 20-30% higher in the years 4 to 6. Over a time period of 11 years, the mean yield was enhanced by 11% under reduced tillage, obviously due to better drought resistance of the crops. Reduced tilled soils contained 17% more humus (0-10 cm depth) and 37% more microbial biomass, resulting in better soil structure and higher water retention capacity. Reduced tillage did not reduce the protein content in wheat. The use of slurry increased yield and protein content in cereals compared to manure compost. The bio-dynamic preparations had an effect on soil properties and wheat grain quality in the first year only. The data originating from this experiment were used for energy balance and greenhouse gas calculations. According to a Life Cycle Assessment (LCA) approach, reduced tillage had less climate impact and consumed less energy than the plough system.
Reduced tillage systems were also tested on loamy soils in Muri (Canton Aargau) and in Aesch with application of either mineral or organic fertilizers. Averaged over four years yields were about 10% lower in reduced tillage compared to plough systems, corresponding to the results obtained on nine organic pilot-farms.
On-farm Conference, Schlatthof, Aesch, BL:
CORE Organic Project TILMAN-ORG
Current project funded by the Coop Sustainability Fund
Boden- und klimafreundlicher Bio-Ackerbau
Peer reviewed publications: