The whole vast edifice of agriculture depends on soil. Maintaining soil health is therefore top priority for farmers – without good soil, there is no food or profit.
So let us look at the real nature of soil. It is the skin in which this planet is clothed. It is an organic and living part of the earth. Just like our skin has pores, layers and vessels, and is constantly involved in interactions with the environment, soil is also full of dynamic interactions. It is a universe in itself, with its own systems of checks, balances and synergies. We need to recognise this. We need to understand that it is not a passive or dead layer waiting for us to mix it up or re-order it.
With this in mind, let’s dig deeper into what tilling is and what it entails.
Tilling is a deliberate disturbance that we cause in the layers of the soil. Tilling moves the soil in such a way that the fertile top soil gets buried under the less fertile subsoil, which now comes to rest on the top. When this happens, the rich humus of the top-soil is lost to the plants.
Also, the insects and soil organisms that inhabited the subsoil till then, are now on top – in an environment, they are not adapted for, and so they die. This upsets the natural synergy between soil organisms that would otherwise have kept the soil composition balanced. In addition, the earthworms – those absolutely crucial beings that we should revere and protect – are killed in the process, either because of the mechanical movement of tilling or because their tunnels and passages are broken and buried because of the changes caused by tilling.
Further, tilling with heavy machines totally compacts the soil, making it virtually impermeable to water. In their natural habitat, earthworms are known to travel anywhere from 22 feet to 150 feet a day. Their movement creates tunnels through which water and air reach lower layers of the soil.
Heavy tilling forces shut all these tunnels, and since the population of earthworms is now significantly lowered, there aren’t enough of them left to build more tunnels and keep the soil moist and aerated.
As a direct result of this, the soil becomes dry and dense, and rainwater, which used to be our primary source of water cannot find its way into the lower layers of the soil – it runs off. (In addition to being tilled, if this land is also laced with chemical fertilisers, the runoff creates all kinds of poisonous trouble, but that’s a story for another day). Thus there is no way for groundwater to be replenished naturally.
Now let us see what else happens when soil is tilled – the green cover of the soil, composed of small plants and ‘weeds’ is destroyed.
The loss of this green cover, rich with semi-decomposed organic matter which in turn retained moisture and could provide enough water for the plants and trees, renders the soil even more unfit to support plants. This soil now has to be externally watered by us all the time. No wonder farmers are facing severe water shortfalls.
Look at this situation from the roots’ point of view. The roots now have very less water naturally available. They also have to force their way through the compacted soil because its porosity is lost.
So, naturally, they do not function at the optimum level. The typical reaction of the unaware farmer to this is to worry about the stunted growth of the plants and then add some chemical fertilisers to try to help. The chemicals further impact the remaining life in the soil, and a downward spiral of chemical farming begins.
So how would tilling work in the olden days? In those days, a single person would take one or two bulls around the field with a manual plough. Each foot/hoof fell in a small little area – it was nothing like the large machines pressing down on the field that we see now. Also, the manual plough did not bite down as deep as the mechanical ploughs now do.
Reduced tilling, or no tilling, brings direct benefits to our farming systems. It offers the following positive features:
- Keeps natural channels open for water to percolate.
- Retains earthworms and in turn other organisms within our soil, thus maintaining the life balance of the soil.
- The organic matter that is known to retain moisture and give a slow release of water back to our plants/trees, is maintained.
- This, in turn, keeps fertility levels better and precludes the need for artificial methods.
Our farming practices should complement the natural ways in which plants and forests have flourished on earth till now. It is important for us to think about what it is we’re doing before doing it.
(Alladi is an organic farmer and teacher who has a long experience in organic farming. He is not the talking type, but a doer who doesn’t mind getting his hands dirty, if it can serve some useful purpose. For any queries please call 9840277566 or email email@example.com or firstname.lastname@example.org)