Few gardeners will deny the usefulness of glyphosate – it kills most plants on a single application. If used carefully it can be applied selectively, for example, to eradicate couch grass from a shrub border. There would appear to be only a small health risk to the occasional user of the product, though a much larger risk of collateral damage to plants, insects, amphibians and soil organisms.
Unsurprisingly such risks are downplayed by the manufacturers, like Monsanto, or by other apparently reputable authorities who rebut claims that, for example, it causes cancer in humans – even though Monsanto was forced into an enormous payout, reduced on appeal, to a Californian groundsman who linked his cancer to the use of their glyphosate product marketed as Roundup.
For a chilling insight into how big business operates in the sphere of ‘fake news’, google ‘who finances climate change denial?’ to get a picture of the potential unreliability of reference sources. I tend to trust the information contained within a 20-page document produced by Friends of the Earth; others may not.
All that said, however, it is the agricultural use of glyphosate that underlies an international campaign to have the product banned. Farmers use it in two principal ways: to ‘clean’ fields prior to sowing a crop and as a desiccant applied directly to the crop immediately prior to harvest to enable greater control of that process.
The successful efforts to achieve weed-free fields have resulted in a dramatic decline in biodiversity, and by no means in just the obvious ‘indicator’ species, like the birds, for example. which are rapidly disappearing from our countryside, having once depended on the plants that the farmer has eradicated.
The use of glyphosate as a desiccant, however, puts that substance directly into the human food chain. Defra tests found that almost two-thirds of wholemeal bread contained glyphosate. The World Health Organisation’s International Agency for Research on Cancer suggests that there is no safe level of glyphosate in food. Some scientists speculate that coeliac disease, as well as some forms of ‘gluten intolerance’, may actually be indications of systemic glyphosate poisoning rather than an allergic reaction to gluten (Samsell and Seneff, Interdisciplinary Toxicology, published online Dec. 2013; the same authors have argued that glyphosate may contribute to the obesity epidemic, autism, Alzheimer’s disease, Parkinson’s disease, infertility, depression, and cancer).
A 2017 study of Government data by Oxford Economics showed that 5.4 million acres of farmland across Britain are treated with glyphosate annually; and US Geological Survey data indicates that glyphosate is present in more than half of all surface waters, soil and sediment.
But perhaps the most insidious aspect of the glyphosate controversy is the genetic modification of plants to make them resistant to the pesticide. ‘Roundup Ready’ crops, including soybeans, maize, canola, and cotton, can be sprayed with the Monsanto product throughout the growing season without killing the crop but ensuring that the harvested product contains the pesticide - a fact that even Monsanto admits to. And farmers are legally prevented from the time-honoured practice of saving a small proportion of their harvest to use as seed the following season. Their traditional renewable resource has been turned into a non-renewable, patented commodity: the ‘intellectual property’ of Monsanto who, along with Du Pont and Syngenta, now controls more than half the world’s seed market. This situation has led to an epidemic of suicide amongst Indian cotton farmers – a link strenuously denied by Monsanto (see www.theguardian.com/global-development gallery 2014).
Whether this wider picture affects the gardener’s view of glyphosate will depend on the individual. But there are alternatives available in the battle to control unwanted plants. Gardens did exist before Monsanto.
At Airdlin Croft we have been experimenting in recent years with various mulching materials, all of which facilitate weed control by excluding the light necessary for growth. Even invasive subjects like Lamium can be eliminated by the simple expedient of covering with a mulching fabric (reusable), though the process obviously takes longer than a few applications of glyphosate (in the case of Lamium, and other undesirables like Bishopweed, a single application of chemical is ineffective).
Our main method though has used cut grass and/or composted wood chips to establish new shrub and tree plantings. Both materials, either combined or used separately, achieve the similar result of preventing the germination of weed seeds in the soil below. Unwanted plants that spread vegetatively are less easy to control this way – it just takes longer – but these can be eliminated by mechanical means in the season prior to planting. Even couch grass gives up the ghost if repeatedly hoed.
Clearly there exists a difficulty in verifying the accuracy of information sources – and obviously, there is a degree of personal sacrifice involved in the decision to renounce the use of glyphosate; but if that decision contributes to a healthier and richer environment then some might consider that worthwhile.