Does ploughing actually damage soils and crops?

David Gregory-Kumar
Science, Environment & Rural Affairs Correspondent

image copyrightHarper Adams University
image captionUnder the microscope you can see the huge range of organisms living in the soil

A tractor dragging a plough through rich soil and breaking it open is one of the most familiar images of farming. But is this most traditional of agricultural activities doing more harm than good?

All last year we followed farmer Jake Freestone as he stopped ploughing on his farm in the Cotswolds.

Instead he used a new piece of machinery to directly drill seeds straight into the ground without any need for ploughing at all.

This is "no till" farming and it is becoming more popular.

There are economic benefits, Jake was able to reduce his tractors from two to one for example, but he was also interested in the improvements no till farming brings to soil quality.

The theory is if you don't go dragging a big metal implement through the ground several times a year, earthworms and other organisms are left alone to improve the soil and that will benefit the crops you grow.

And yet there's not actually a lot of evidence to support this idea.

An experiment

image captionThe traditional ploughed field shows many more weeds

So in a field near Wem in Shropshire a team are trying to do something about this.

Tim Ashton is a lawyer by training, but when he came to take over the family farm he decided to improve his farming knowledge with an MSc at Harper Adams University.

He also decided to switch to a no till system, something his father John had tinkered with in the 1970s; although the technology wasn't quite up to it then and John eventually went back to conventional farming.

Surprised at the lack of published research into the benefits of the system he was gambling the farm's future on, Tim set up a simple experiment with the help of Harper Adams and Oxford universities.

A field where strips of land are ploughed and the rest of the field is not.

image captionIn a field in Wem an experiment is taking place that no one has done before.

In went a standard crop of wheat and Tim settled back to see what the difference between the ploughed and unploughed soil would be.

The focus of this experiment is the long-term health of the soil.

Oxford University is carrying out sophisticated DNA analysis of the many organisms living in the ground.

But to the surprise of everyone, the difference between the two approaches showed itself much earlier in the actual crop itself.

As Tim showed me, the no-till wheat is stronger and healthier and it's growing in soil with far fewer weeds.

In comparison, the wheat in the traditionally ploughed ground is struggling and there are also a lot more weeds.

Reassuring results

image captionResearchers have been studying the plants and the soil to see the impact of ploughing

Such a pronounced difference and a clear benefit to no-till is reassuring for Tim and other farmers who want to make the switch.

Changing your entire farming system can be a pretty rocky experience, the first year of no-till is notorious for drastically reduced yields.

Now there's concrete data that there are definitely benefits.

Fuel savings

Of course these are preliminary results and there's still more in-depth analysis of the soil organisms to be done, but there are two other benefits to be considered here.

First, the soil should also retain more water, which is good news for the rest of us when it comes to flooding.

Secondly, the economic benefits and certainly the fuel savings are very real.

Tim's dad John confided to me that the farm's diesel supplier had been on the phone concerned they had switched their account to another company since they hadn't purchased any fuel since September.

The truth? No ploughing means reduced tractor activity and a drastically reduced fuel bill.

You can read more about the experiment on the farm's website here.