Claims of environmental benefits of no-till farming with glyphosate are unfounded and the sky won’t fall in if the chemical is banned, writes nature blogger Miles King

So many words have been written about the herbicide glyphosate (commonly known as Roundup), it seems almost pointless adding any more. But anyway…

Last week the European Commission postponed a decision on whether to renew a licence for the herbicide. They will have to decide by December or face legal action from its maker the US chemical company Monsanto. Monsanto are currently waiting for approval for a merger/take-over from the German chemical/drugs behemoth Bayer. The European Parliament voted (the vote was not binding – just like the UK Referendum vote) to call for the Commission to phase out the use of glyphosate-based herbicides within 5 years, and an immediate ban on all domestic and urban uses. But when it came to totting up each Member State’s vote, there was a small majority of EU countries (including the UK) who voted in favour of renewal. This majority was not sufficient for the decision to be confirmed though, hence the further delay. France, Italy and Austria have been leading the calls for a ban. Germany is now apparently lobbying for a 3 year extension.

What’s all the fuss about? A couple of years ago the World Health Organisation cancer expert group the IARC concluded that glyphosate was “probably carcinogenic”. This means that the evidence is currently not strong enough to conclude that it is definitely cancer-causing, but there are serious grounds for concern. Monsanto, which markets Round-up, but far more importantly has a monopoly on GM-crops which can only grow when glyphosate herbicides are applied around them, has been orchestrating a campaign to undermine both the IARC and its findings. Light is now being shed on this campaign in the US courts, where lawyers for farmers who claim long-term glyphosate use has given them cancer (specifically non-Hodgkin’s Lymphoma) are suing Monsanto. The more one reads of what Monsanto has been up to, the more parallels appear with the Tobacco Industry tactics in the 60s and 70s.

In the UK the most vociferous campaigners trying to persuade everyone that glyphosate is perfectly safe, are those arable farmers who have adopted a no-till or minimum tillage approach to growing cereal crops. No-till means that there is no cultivation before or after a crop is harvested. The seeds are sown directly into the soil, but in order to prevent the crop from being swamped by weeds, herbicide such as glyphosate is applied. After the crop has matured, a further application of glyphosate is applied to desiccate the crop, so it is dry when harvested. This saves money and energy drying what are often rather wet crops in our climate.

One of the main “weeds” that the no-tillers have to contend with is Black-grass, Alopecurus myosuroides. This was not even a common arable weed before the second world war, and only became problematical in the 1970s after a switch away from mixed farming, spring crops and fallow periods, towards a winter-crop monoculture approach to food production. The ban on stubble-burning in the mid-80s further exacerbated the problem. Farmers operating no-till (apart from those few organic no-tillers) now depend on glyphosate amongst a mix of herbicides to keep Black-grass levels under control. So far, Black-grass has not evolved resistance to glyphosate; however, given how much of it is used, it can only be a matter of time before this happens.

The no-till farmers claim that their practices are much more environmentally friendly than conventional arable farming, making all sorts of claims about soil health, carbon storage (for climate change mitigation) and wildlife benefits.  I have searched for quite a long time for any real scientific evidence that no-till leads to long-term increases in soil carbon that could make a significant difference to the UK carbon store, but found nothing. What I have found is evidence that the no-till claims are unfounded. This paper in Nature Climate Change for example: 

One of the big problems for no-till as a solution to climate change is this. As crop material that has been left after harvest decomposes, it releases Nitrous Oxide. This is a far more potent greenhouse gas than Carbon Dioxide. So any benefits from no-till are likely to be wiped out by the N20 released.

Equally, there is no evidence (that I could find) that no-till is better for wildlife of arable farmland than conventional agriculture. This may not be particularly surprising, given that the farmland is given repeated doses of glyphosate, which kills all wild plants, on which insects, and the birds that eat them, depend. Anecdotal evidence from no-till farmers themselves suggests that ground-nesting birds such as skylarks benefit from the lack of disturbance from cultivation, but this needs backing up with proper studies.

And this is really my concern about the ubiquitous use of glyphosate. Yes, it’s possible that it is a carcinogen, and given that it and its main breakdown product AMPA are now pretty much in everything and everyone, then some people are getting cancer as a result. But then cancer is a very common set of diseases, caused by a whole range of things that we do as humans. From an environmental perspective though, glyphosate use is having a series of interlocking impacts. If wild plants are constantly being prevented from becoming established, or surviving in farmed landscapes, this not only has an ongoing impact on their own chances of survival, but also on all the wildlife that depends on them. Our countryside, and indeed large parts of the countryside in Europe, is being systematically cleared of wildlife. Last week’s report that insect populations across a series of nature reserves in Germany had declined by 75% in 25 years is not unrelated. Farmers on social media were writing “but glyphosate’s not an insecticide, so it can’t be affecting insects”.

If wild plants are removed, insects have nothing to eat, nowhere to hide and nowhere to lay their eggs.

Another lesser known impact of glyphosate is on microbial communities. Glyphosate and its main breakdown product AMPA are amino acids but glyphosate also acts as a selective antibiotic. Certain bacteria are able to digest and benefit from glyphosate in soils but also in animal guts, while some evidence indicates that glyphosate may help drive antibiotic resistance.  Microbiologists are also concerned that glyphosate may be affecting the balance between relatively harmless gut bacteria and their more pathogenic cousins, such as Clostridium difficile. Given how ubiquitous glyphosate now is, this is perhaps the single biggest issue for glyphosate on human health, but is widely ignored. We also know almost nothing about its impact on soil microbial and fungal communities – the assumption is that there is no impact.

And this brings me to the Precautionary Principle. This principle is woven into the legal fabric of the European Union, and we may well lose it as a result of Brexit. Apply the precautionary principle to glyphosate and, on the balance of current evidence, its use would be severely restricted, while far more research would need to be instigated. However, if we leave the EU and the EU does phase out glyphosate, we will be left with little choice but to follow their lead. Because otherwise the UK food exports to the EU would be banned. This is what is particularly exercising Monsanto (whose lobbying tactics in the EU have led to them being banned from the European Parliament estate) but also countries that have wholesale adopted GM farming, which is totally dependent on glyphosate.

Former Brexit minister Oliver Letwin believes that we should adopt the Precautionary Principle into UK law, but then ignore it for glyphosate. This opinion piece (we are blessed to have a weekly thought from Letwin) is from our local rag the Dorset Echo. 

If you believe some of the claims from the farming community, the UK food supply chain sky will fall in, if glyphosate is banned. I’d just point to one previous example – paraquat. Paraquat was widely used in UK agriculture until it was banned (by the EU) in 2007, despite a vociferous campaign by the UK agrochemical industry – Sweden banned it in 1983 because its toxicity was already well established. Did the sky fall in? no.  Scandalously, Paraquat is still manufactured in England, for export to countries where it is not yet banned.

There are certainly strong claims to retain glyphosate for specific applications – such as killing Japanese knotweed, where it threatens buildings or infrastructure. Scare stories like this one, where the rail infrastructure of the UK will be threatened by a glyphosate ban, do nothing to help those who argue sensibly for continued, careful use in specific circumstances.

The saga of glyphosate is also emblematic of a wider debate, which we will need to have sooner or later. Farmers are forced to farm in unsustainable ways, because consumers refuse to pay the real price of food; and the big retailers take far too big a chunk of that price for their shareholders (which may include some us if our pension schemes invest in them.)

How to untangle this particular gordian knot? At least some people are thinking about it – and this new commission on the future of food and farming is welcome.


Miles King is a well-known blogger on nature who has worked in UK nature conservation for 28 years. This article was first published on his blog and is reprinted on GMWatch with the kind permission of the author.

Image: A glyphosate-sprayed arable field, courtesy of Miles King.