Wednesday 28 June 2017

Organic No-Till

The concept of no-till organic or non-organic with cover crops ticks pretty much every box. Lower fixed costs, lower variable costs, less time spent on a tractor, better soils, more efficient water infiltration, more earthworms and if you practice it right the chance of more stable and higher yields. Fitting neatly into the “Conservation Agriculture” bracket it even sounds a bit sexy and something that the average shopper might want to pay a little more for, so we could be adding higher prices to the list of plusses. What’s not too like?

For organic farmers like me there is one stumbling block. Glyphosate. We can’t use it. 

From what I am being told the key element for no-till success is the ability to kill your cover crop with glyphosate pre-sowing, but not according to Jeff Moyer who published “Organic No-Till Farming” in 2011. The trick is to get your cover crop to anthesis when it’s just about used up all it’s energy reserves and then bruise it to death with crimper roller. So no excuses for us soil moving addicted organic farmers then?

I know two organic farmers who are dipping their toes into the concept but I am taking a rather more cautious approach and have signed up to an Innovative Farmers project with Anglia Farmers and am one of the fools giving it a go with some trial work starting this autumn. As harvest 2016 wasn’t particularly kind to us, for the first two years I am going to try and achieve my part of the trial with equipment I already own. The plan goes as follows:

Year 1: spring oats. The preceding crop is spelt and by the time you read this article we will have under-sown into the spelt, in half hectare strips, buckwheat, phacelia, mustard and berseem clover. They will be sown individually and in a mix. Under-sowing the cover crops in May should mean that after harvest they should be well established and get to anthesis before winter when I will roll them with my Cambridge rolls. If that fails to kill them I will have a second chance of cover crop death through frost action over the winter. The best outcome I am hoping for is a thick mat of cover crop to smother weeds over Christmas and then an easy spring for me to slot in the spring oats with my low disturbance Cameleon drill. The worst outcome doesn’t bear thinking about. 

Year 2: winter beans. Again, the intention would be to under-sow a cover crop in the previous year’s oat crop in April/May with the most successful option or a mix of what did best in year one. However, to sow the beans I am considering putting some low ground disturbance Sabre tines onto my existing Cousins sub-soiler (not very no-till I know) and dribble the bean seeds down the back of the tines. Will it work? Will we actually get a frost? Your guess is as good as mine. 

Year 3: spring barley. Beans are a notoriously dirty crop for organic farmers, but having not disturbed the soil (much) over the preceding two years and under-sowing a cover crop in the winter beans, maybe, just maybe we might get away with a weed free entry into a spring barley crop  which itself will be under-sown with a two year diverse grazing ley.

Year 4 and 5 will be the fertility reset button for the rotation and provide grazing for my sheep before going back into a spelt crop in year 6 and the whole malarkey starts again.

But, how will I terminate the ley and start cropping again?

This is where I put my Jeff Moyer No-Till New Testament down and pick up the Zonal Tillage Old Testament of Gary Zimmer. Conveniently Reverend Zimmer still falls under the religion of “Conservation Agriculture” but he does allow zonal tilling with cover crops which enables me for at least one part of my rotation to “dig” (do you see what I did there) either my ageing Horsch Terrano or Gregoire Besson out of the nettles and mineralise a bit of nitrogen. Phew! 

And that’s it. Obviously, there will be howling errors in this ridiculous plan and I would be extremely grateful if you would email me (jpawsey@mac.com) with your thoughts and advice. At least I will be able to blame someone else if it all goes horribly wrong. Just before you do write though, I may have made a mistake with the berseem clover and the frost idea, so don’t remind me.

I have no idea how I will be farming five years from now, but what I do know is that it won’t be how I am doing it now. I also know that to farm organically and get enough yield to make a profit we have to mineralise some nutrients. Given that our organic matter has gone up since I started farming organically I am pretty sure that we are headed in the right direction with our existing system of using cover crops and leys and that has involved a lot of ploughing and tillage. However, we can always do better. 

In reality, if we continue to rely on legumes and animals to build fertility, a biological approach to weed, pest and disease control we will always have to adopt a managed approach, which will include no-till, zonal tillage and (I haven’t mentioned it yet) the plough.

Written for Groundswell Event, June 2017



No comments:

Post a Comment