Potential of controlled traffic farming with automatic guidance on an organic farm in the Netherlands

Some organic farms in the Netherlands use RTK-DGPS guidance of machinery over fixed traffic lanes to achieve non-trafficked cropping zones with optimum soil structure. These lanes are not yet used for harvesting and primary tillage. The potential of such a seasonal controlled traffic farming (SCTF) system was evaluated. In an on-farm field experiment in green pea, spinach, onions and carrots, SCTF with traffic lanes at 3.15-m centres was compared with conventional random traffic farming (RTF) using low ground pressures in spring from 2002 till 2005. Compared with RTF, the topsoil structure in the SCTF system improved, also in terms of lower spatial variability, for the crops sown on the flat but not for carrot grown on ridges. Crop yields increased significantly in green pea, spinach and planted onion but not in carrot and sown onion. SCTF resulted in a reduction of N2O emissions by 20-50%, and reduced CH4 emissions by a factor 2-12 when compared with RTF. SCTF was economically feasible for hypothetical 50-ha and 200-ha organic farms. An important advantage of SCTF over RTF is the increase in number of days that field operations can be executed. Keywords: Controlled Traffic Farming, Organic, Nitrous oxide