Opinion: The government needs a lesson in thermodynamics
Mike Neaverson © Tim Scrivener Before building my last potato store, I instructed a test piling company to report on conditions below ground.
Admitting defeat two days and 27m of vertical drilling later, we had burrowed through nothing apart from silt, sloppy mud and a few cockleshells. You could describe our land as fairly bottomless.
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What this means for the construction of potato stores is some very expensive footings. But what it means for well-established crops is that they are nigh-on impossible to drought out.
And with such an abundance of minerals at their feet, yields are generally high and requirements for some nutrients low.
Farmers in this area have, therefore, been noticing for decades that the likes of RB209 – while a good guide – can in some areas be bettered quite considerably.
Fifteen years ago, a group of forward-thinking growers clubbed together to pay for their own independent replicated trials to inform decisions commercially.
And after the retirement of Dr John, our much-preferred trials man, unfortunately for them they’ve ended up with yours truly running it.
Fifteen years of back data allows you to apply the challenges of today into the results of yesterday.
For example, when nitrogen fertilisers were touching £1,000/t a couple of years ago, it allowed members to tailor fertiliser programmes with data from our own soil types and previous cropping.
It enabled us to say we ought to reduce N rates by X, and that would likely reduce yield by the economically optimum Y.
The same scenarios have been pondered for all the major nutrients over the years, and many minor ones too.
With 15 years of data, we are therefore in a highly educated position to say what the government’s proposed £50 to £75/t fertiliser tax will do to production in this postcode.
Assuming grain and fertiliser prices otherwise remain static, we anticipate that we would apply 15kg/ha of N less, which would in turn reduce yield by 0.17t/ha, and lower farm margins by £40/ha.
Multiply this number by the 2.5m hectares of cereals grown in the UK, and that’s the best part of half a million tonnes of domestic grain production flung to the environmental wolves and £100m scrubbed off our collective bottom lines. World-beating growth for you.
Steve Reed has told British farmers we need to do more with less. And I can already predict next week’s letter page: “Mr Neaverson is wrong; I use a potion that is 7,000 times more efficient”.
All I can say is that I’ve seen many of these products on farm from the combine seat and in many, many trials, and I have never been tempted to call their efficacy anything other than “inconsistently nuanced”.
There is no such thing as a free lunch and there is no scientifically validated silver bullet to make up the difference.
Commercial grains need nitrogen. Nitrogen needs energy. And unless you have found a way to bypass the laws of thermodynamics, that energy is either going to come from the bag or from a reduced yield.
And in this particular case that energy is going to come in the form of 500,000t of imported grain grown to lower standards with tax-free fertiliser.
British agriculture will survive a £50 fertiliser tax. But as part of Labour’s wider agricultural reforms, we can confidently say that come the next general election most of their rural MPs will not.