What is ULD No-Tillage and Micro-Management of residues?
ULD (Ultra Low Disturbance) No-Tillage is the ultimate in Micro-Management of residues in Conservation Agriculture.
There is little debate amongst soil conservationists that true Conservation Agriculture is as much about the management of crop residues as it is about ceasing to till the soil. But to date, residue management has mainly focused on how much residue is left on a field as a whole after passage of a drill or planter. It makes no distinction between the residues over the slot zone compared with residues on the whole field.
Micro-management of residues focuses on managing residues specifically in the slot zone alone, since this can have a greater short-term influence on the success or failure of a no-tillage event than ensuring that a target amount of residues remain on the field as a whole. Indeed, many designs of no-tillage openers sweep residues away from the slot zone or mix them with soil to avoid blockage. While such openers may well meet field-scale residue-retention goals they do not meet micromanagement goals and therefore they increase the risks of failure at drilling.
ULD No-Tillage specialises on returning residues over the slot during the drilling process, where they have a major influence on the microenvironment within the sown slots. This, in turn, dictates the success or failure of seedling emergence, especially in sub-optimal soil conditions. At its best, ULD returns 100% of available surface residues over the slot so that no bare soil is visible. This is a demanding task that only one specialised no-tillage opener (Cross Slot) consistently achieves.