I’M old enough – and I wouldn’t have to be very old – to remember when the main sustainability challenge to our food system was food miles. Shipping or air-freighting staple foods, already produced to dubious standards of sustainability, over vast distances could be economical only if the environmental costs were not being adequately priced in.

Groups such as Animal Rebellion and its ideological bedfellows would have us believe that food miles no longer count. That, at least, is the conclusion we must draw from their recent pronouncements, which present a vision of a Scotland without livestock farming and aquaculture, where land and water hitherto used for those purposes is given over to rewilding. Nature would take over once more.

The question they do not answer is what, precisely, would we be left with to eat?

One previously favoured refrain from the plant-based movement would appear to have fallen away: that livestock farmers should simply convert to arable, growing crops instead of raising animals. It would make perverse sense for this argument to be ditched because the suggestion is simply impossible.

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As this newspaper revealed in January, Scottish Government research has defined 86% of Scotland’s agricultural land as ‘Less Favourable’, meaning it is only really suitable for livestock farming and, sparsely, harvestable animal fodder. Such land cannot be given over to arable farming because the crops will not grow.

These facts were brought to light following the decision of Edinburgh City Council to endorse a so-called Plant-Based Treaty. Not a treaty by the ordinary meaning of the word, this is in reality a campaign manifesto by activists working for a startup NGO.

What exactly Edinburgh intended by signing up to it remains a subject of some mystery, considering its own analysis pointed out that most of what the document grandly calls its ‘demands’ fall outwith the scope of a local authority, but the manifesto offers at least some clues.

No expansion in any part of the livestock farming or aquaculture sectors. Tax hikes on meat and fish. Government-sponsored propaganda advocating veganism. And, perhaps most insidiously, since a council could conceivably implement it, a “transition to plant-based meal plans in schools, hospitals, nursing homes, prisons and government institutions”.

The Herald: Quinoa won't grow in ScotlandQuinoa won't grow in Scotland (Image: free)

If Edinburgh City Council is serious, not only will meat and dairy be taken off school menus regardless of parents’ wishes or the nutritional needs of their children, but old age pensioners, in the twilight of their lives, could be told by council bureaucrats that the diets they have been enjoying since infancy will be denied to them. All because the council knows better. This in the name of humanity.

I grew up in Perthshire surrounded by the best soft fruit production in the world. Edinburgh, too, is ringed with other parts of the small proportion of Scotland’s agricultural land that is suitable for arable farming. There it is mainly crops and vegetables.

We are left with a distinct impression of Edinburgh councillors and their officials gazing down from their plant-based ivory towers at the enclosing land and its farms, noting the abundant crop production and feeling quite satisfied about their schemes for Scottish farming. If they deigned to leave Lothian, they would swiftly discover that the reality on, and indeed of, the ground elsewhere is quite different.

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Ruling out livestock farming would not only remove several major food sources and ravage personal freedom, but would blight Scottish agriculture and its dependents as a whole.

‘Plant-based’ advocates frequently express enthusiasm for low-intensity and organic farming; but with no access to manure and slurry that sector could not survive.

The attack is on all animal agriculture, so there would be no more sheep farming for wool – a sustainable fibre whose production, incidentally, is often supported by the sale of lamb.

Harris and Hebridean tweed, respected and admired the world over for the centuries of craft its producers have invested, would end production overnight, all in spite of the professed commitment in the 'treaty' to the “protection of Indigenous Peoples; their land, rights and knowledge”.

Livestock farming, like all of agriculture, sees its fair share of unsustainable practices. The correct response is to tackle them, because it is true that not all meat is created equal. By pretending it is, and basing its ideological assault on meat consumption on that pretence, Animal Rebellion has argued itself into a corner. It invites us to draw a contrast between the sustainability of plants and meat: we should accept.

These ‘environmentalists’ seriously maintain that instead of eating meat harvested sustainably from deer that would have to culled in any case for the protection of biodiversity, we had better derive those calories from quinoa, grown on deforested land in Bolivia before being air-freighted to us over 6,000 miles. Those calories won’t grow on Scottish land.

This is a reductio ad absurdam – but it didn’t take much.

David M Bean is Parliament and Government Relations Manager, Countryside Alliance