WHY DO WE HAVE TO TREAT OUR SOILS LIKE DIRT? by Nick Woodyatt, Soil Fertility Consultant at Aiva Fertiliser
Normally when starting an article there is much gnashing of teeth and wandering around the garden, or pub in my case, deciding on how to help and enlighten our industry (hopefully). But seeing as it did not stop raining during the autumn/winter, on this occasion the decision was somewhat easier. My town should have been re-named Upton under Severn. On my rounds I saw two four-wheel-drive tractors tied together pulling a plough through the field which looked like toothpaste and all eight wheels were spinning as they pulled themselves down onto their axles: really. Funnily enough the managers of this farming area were having a heated debate at the same time on whether to use a direct or strip till drill which simply amazed me. We all know that if we lose Glyphosate then getting to a good position [soil wise] for direct drilling is going to be so much more difficult, but not impossible. What is perhaps now becoming obvious, is the effect that climate change will have on this method of growing, with longer and wetter periods, and yes, I do realise now we’ve gone from one extreme of constant rain to the next which is as dry as a party in a nunnery, but that still has the same effects. On my farm walks I saw the relentless tapping of billions of raindrops on the soil surface produced an 80-100mm cap that has the consistency of wet play-dough which, is either going to cap over growing crops or produce an airless situation in to which seeds will be put. Indeed, I watched seeds direct and strip drilled (on good soils) and I have had to ask the question, ‘Why’? The direct seeds are firmly encased in a solid wall of mud so as they chit, they will more than likely rot. The strip tilled seeds are more of a surprise. I tripped over this problem in the wet autumn when I was told that my bacterial application had stopped having the desired effect on clubroot in cauliflower. When I visited the problem it was plain to see that the soil wasn’t 14 DIRECT DRILLER MAGAZINE
ready for this method of drilling and the drill had in effect formed shallow drains across the field, therefore producing an anaerobic environment for the soil life hence allowing the harmful anaerobic pathogens to run amuck. Now if it had stayed like that I wouldn’t have been too alarmed, but since then, I have noticed that the lifted rows left by the strip till are overtly wet compared with the surrounding soil regardless of how good the surrounding soil is. The phrase that we earn the right to use any specific piece of machinery is oh so right.
The importance of air This is leading me to suggest we need to see that there are times when sowing isn’t going to work (difficult to say the least) and we need to stick to the rule that the soil needs what the soil needs, to get air into it. If you can’t find it in you to see that I may have a point then get a friend to strangle you and see how long you can last and no, there is no difference (only in time). We discuss soil, nutrients and where unenlightened, agrichemicals, but how often do we look at air and its importance. Without a free and open soil structure everything else starts to fall apart and your inputs will rapidly rise whist your profits rapidly fall. A perfect soil contains 50% air, and this impinges on so many plant processes and as farmers who are or considering min/no till we really need to understand that this allows: • Fresh air into the soil where bacteria such as Azotobacter can convert gaseous N into a plant available form saving you money. • Better penetration of applied nutrients in whatever form they are applied to avoid this surface rooting that we see in many crops. • Carbon Dioxide from bacteria from the soil up into the leaf increasing photosynthesis and increasing your yield (Why do you think the stoma are on the underside of the leaf?)
• Roots to penetrate deeper to get to more nutrients allowing you to reduce your inputs and this increases drought resistance. • Better roots which allows more sugar release into the soil which feeds the soil life which in turn feeds your crop and resists disease therefore less inputs (the circle of life). • Better penetration of earth worms who do so much for you free of charge that it is one of the wonders of the world why we try to kill so many (oh, I remember, it’s the profits of the chemical companies, silly me) I could go on and on, but I think you get the message, start with air and work out from there as against start with Nitrogen and work for the chemical companies. However, as we have to work with excessive wet and excessive dry periods is there anything that we can do to alleviate the situation and of course the answer as always is yes. Many farmers who are going down the min/no till route are doing it because they feel a moral duty to improve their soils for future generations and those like me, fancy making a profit occasionally. Those who are doing it just as a Black Grass control have stopped reading ages ago.
It’s more than the right products Firstly, let’s make it clear that to improve a soil for both dry/wet periods isn’t just a case of buying the right products as some want us to believe. One farmer has been told that by applying a good soil wetting agent excess water will drain away; this was said to a farmer whose soil was under water so we did have to wonder where the water would go. There are any number of ways of moving forward and I am going to mention my friend Tim Parton who was `Soil Farmer of the Year 2017’, `Arable Innovator of the year 2019’ and is `Sustainable Farmer of the Year 2020’ and has transformed his soils over the last 10 years just by judicious use of ISSUE 10 | JULY 2020
