It takes up to a thousand years to produce the top few centimetres of soil and its rate of formation is proportionately linked with the number of inhabiting worms - the largest contributors to soil maintenance. Capable of moving and mixing vast amounts of topsoil, these structural engineers are responsible for creating soil macro-pores which are vital for efficient oxygen and water circulation. Furthermore, earthworms shred surface residue and pull it down into the ground, making it more accessible to microbes which can then process the debris and convert it into humus.
Inversion tillage techniques and intensive use of pesticides have a detrimental effect on earthworm populations and the wider soil fauna community, disrupting the natural process of soil rejuvenation and maintenance. Small earthworm count means poorer aeration, water circulation and overall soil structure. Reducing such interference as much as possible is therefore the first step towards effective soil management.