The majority of soil breaking actions are carried out to produce a seedbed and establish a crop, although activities such as subsoiling, soil aeration and mole ploughing are carried out as remedial actions primarily for compacted soils. Weed suppression with hoes and other mechanical weeding machinery also break the soil. As we learn more about the impacts of breaking and turning over the soil, the need for such cultivations are increasingly being questioned.
More and more farmers are seeking ways of minimising their cultivations to limit this damage. Whilst groups of farmers are actively investigating methods to reduce reliance on the plough, to date most organic farms use it to control weeds, and incorporate organic matter from one crop, in preparation for the next. Despite the disruption caused by ploughing, organically farmed soils have an average of 21% more soil organic matter (SOM), so if you get the machinery and timing right, appropriate cultivation can be an important part of building healthy soils.
The damage to soils from machinery will depend on the time of year, depth of cultivation and frequency of such actions, as well as the soil type itself. Such actions turn the structure of the soil and all the SOM producing flora and fauna upside down. Repeated use of machinery can reduce SOM, as soil microorganisms become more compromised and less able to re-establish their ecosystem.
Arable and Soils Advisor
Jerry has experience in arable and mixed farming having run the family farm in Devon for 25 years. The farm was initially a dairy farm, before converting to organic and being run as a beef, sheep and arable unit. Alongside farming he converted a range of farm buildings into a holiday cottage complex, was chairman of a local farmer owned co-op grain store and became involved in the national grain supply chain. Jerry can often be found wherever the Exeter chiefs Rugby team are playing!