Non-inversion tillage in organic arable cropping

Summary

The opportunities for using an non-inversion tillage (NI) approach in organic systems has not been well investigated by research and what research has been done has not perhaps been sufficiently long-term. The benefits of the system in terms of the economics of establishment and the improvement in soil quality make the system attractive, but it is a system that will take some time to get established and is one that will require the farmer to “hold his nerve” as grass weed, perennial weed burdens and slug predation may increase in the early years of implementation.
In conventional systems and the POB work yields have reported to drop when implementing an NI system. This is before some of the benefits of a better quality soil are seen, but in the work done by Dr Michael Brandt in an organic system no yield drop was experienced. This was also the case for Danish work done by Per Schonning. Phosphate (P) and Nitrate (N) losses can be reduced as soil structure improves and becomes more stable. Better water ingress into the soil will reduce run-off and sediment and P loss and better water retention in the soil structure will reduce leaching potential. This is perhaps particularly the case at the time that the ley phase of a rotation is broken when greatest risks of N leaching occurs particularly if this coincides with significant rainfall.