Last Friday, I found myself doing something that people normally do only in their own gardens; planting trees.

But, on this occasion, the trees in question were not being planted in my garden. They were being planted at Dorset County Hospital and at Damers School in Dorchester.

The remarkable thing about this small, local activity was that it formed a tiny part of what is by now an impressive global initiative.

This initiative is the brainchild of the well-known Labour MP Frank Field- who has a considerable talent for coming up with interesting ideas.

The project is called the Queen’s Commonwealth Canopy Project. It consists of a whole string of coordinated arboreal initiatives stretching across the vast terrain occupied by the Commonwealth.

In Queensland, Australia, these activities are focussed on the national park that houses the only known examples of the endangered Bulburin Tree as well as a host of other exotic species.

In Singapore, the centrepiece is the remarkable botanic gardens, which provide a home for a range of important rainforest trees.

And in Britain, as will be obvious, in constituencies up and down the country MPs are planting trees in just the same way that I have done.

This wave of activity, orchestrated across many thousands of miles, serves three simultaneous purposes. It seeks to emphasise the colossal importance of trees in adorning the landscape and in sequestering carbon to preserve our planet. It highlights the too often overlooked capacity of the member states of the commonwealth to work together in pursuit of common goals. And it celebrates the Queen’s long and distinguished tenure as the head of the Commonwealth.

Each of these purposes is important - and it is, perhaps, particularly appropriate that, as we head towards Brexit, we should remember not only the relationships we have with our friends and allies across the continent of Europe, but also the potential we have to cooperate with the other members of the Commonwealth to further our mutual interests and to help move the world as a whole in the right direction.

This is not, after all, a negligible or even minor association of nations. We should remember that the 53 countries of the Commonwealth contain some 2.4 billion people - roughly a third of the world’s population. And, between them they have a gross income of some $10 trillion per year - putting them very firmly in the big league globally.

The Queen may be the Monarch of a relatively small island state; but her canopy stretches across something much larger.