In novels by Enid Blyton, it was known as “pop”. In Glasgow, the common collective term is “ginger”. Whereas, in Dundee, we spoke exclusively of “lemonade”, whether of the orange, pineapple or cream soda variety.

Whatever the nomenclature, young boys and girls would assiduously collect the empties in order to trade them for cash at their local corner shop.

Now, that harmless childhood pursuit has become, in these troubled times, a significant constitutional dispute, based upon the Scottish Government’s Deposit Return Scheme.

The source of this rammy, however, is not ginger or lemonade or indeed pop. It is politics.

You will know the basics, I presume.

You pay an extra 20p when you buy any bottle or can – and then get that deposit back when you return the empties.

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The scheme, delayed by difficulties, is due to start in March next year. Supporters say it will hugely increase recycling and help protect the environment.

There are practical issues. What will be the impact upon retailers? Will the public respond? What about existing kerbside collections?

However, prowl around the corridors of Holyrood, as I did this week, and you will swiftly discern underlying political anxieties too.

You will learn of anger over a late intervention by the UK Government which the First Minister has described as “sabotage”.

You will learn of uncertainty within the Scottish Government as to the response, driven as they are by a balance of pragmatic and political pressures.

You will learn of a degree of division between sections of the SNP and their partners, the Greens – who are, needless to say, enthusiastic proponents of the recycling scheme.

You will learn of efforts by other parties, most notably the Conservatives, to exploit those tensions.

The Herald: RecyclingRecycling (Image: PA)

And you will learn of deep discontent among some SNP MSPs regarding the handling of this whole issue by the Green Minister, Lorna Slater.

Let us be clear here. Both governments, UK and Scottish, have political aims. The issue of recycling is devolved – and the scheme was backed by Holyrood three years ago.

But the Scottish Secretary Alister Jack intervened at a late stage, citing problems with the internal market structure set up in the UK post Brexit.

Firstly, the cause stated. Mr Jack says he is concerned at the impact upon business and that the scheme in practice is not well designed. He says it can only go ahead if glass is excluded, ready to align with plans elsewhere in the UK.

Next, the politics. Mr Jack is putting Holyrood in its place. He is reminding MSPs and voters that Scotland has another Parliament and another government, based in Westminster.

He is, in short, exercising power to remind us all where power lies.

To be fair, there has been considerable concern about implementation. There have been anxious words from business – although Tennent’s Brewery, whose product is mostly sold in cans, is now fretting about losing competitive edge if glass is excluded.

But be quite clear. This is raw politics. It has been suggested that other UK Ministers might have been relatively content to allow Scotland to go ahead, perhaps seeing the scheme as a pilot.

Mr Jack insisted that the exclusion was best. He got his way.

But Scottish Ministers are now in the game too. They see an opportunity to depict the Jack intervention as an assault on devolution, not just a single policy.

That fits a broader SNP narrative. However, the Greens are also firmly on board, in defence of their scheme. Lorna Slater told MSPs that the UK Government was “torpedoing” Scotland’s Parliament.

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Not sure either constitutional initiative really works. Business – and voters – may tend to see them as exasperating sideshows, given the perilous state of the economy. But there may be some traction and both arguments are understandable in the broader context of Scottish politics.

Pragmatically, though, the Scottish Government is in a bind. Does it bow to the UK edict? Or seek to challenge it, perhaps citing discontent in Wales where the First Minister Mark Drakeford also wants to include glass in his scheme?

Lurking in the background of this decision, the prospect of compensation claims by companies which installed recycling machinery in preparation for the full scheme, glass included.

Which brings us to the implementation of the scheme thus far which has been, arguably, somewhat sub-prime. To be quite clear, most SNP MSPs strongly support the recycling policy. It was a party commitment. They also firmly back the continuing pact with the Greens which creates a Holyrood majority.

Further, the intervention by Alister Jack has tended to solidify SNP support for the policy and the pact. There are, however, hints of growing disquiet. Some in the SNP feel the Greens are sometimes too swift to claim credit, given they only contribute seven votes to the Parliamentary arithmetic. Some would prefer a stronger focus at Holyrood upon economic growth. There is what might be called an “amorphous grouping” within the SNP pursuing that aim.

The issue of growth is specifically excluded from the governing pact. However, the Tories detect an opportunity. Their aim is to present the SNP and the Greens as a package, to suggest to voters that the combination is inimical to Scottish interests.

More generally, some in the SNP find the Greens just a little too zealous, a little too supercilious. Frankly, a little annoying.

Mostly, though, such comments are accompanied by a tolerant smile. Hey, that’s politics.

I do not remotely detect any move within the SNP to end the pact. Opinion regarding Lorna Slater is somewhat sharper.

Several SNP backbenchers categorised her to me as politically inexperienced, even naïve. One said she had palpably failed to grasp the full extent of the political and constitutional challenge represented by the UK intervention.

Another said she should have secured agreement from the UK Government at a much earlier stage. I was told it was like opening a pub, and then applying for the licence. Supporters insist she was working on exactly that within the established framework of inter-governmental relations and that the UK Government changed tack.

Either way, it is a mess. Time to clear up the political litter.