Around here, concrete paving slabs create problems when they are heave up by tree roots. But slabbed footpaths are now being replaced or covered over with tarmac, so the problem of trip hazards on pavements is being addressed.

However, tarmac will still crack and buckle, and some inelegant solutions are being applied in places like the River Rea cycle path. This one involved felling a tree, doing some sort of excavation, then grinding the pavement down and resurfacing the path.

That is not a great way of maintaining mature trees along roads.

But a bit of wider travel showed me that there are more elegant solutions, like this one in Cambridge. Massachusetts, where the slabbed paving gives way to interlocking brick surfaces that ride gently over the roots, whilst also providing a bit of rainwater permeability. Whilst a given bit of brick may heave, it can be relaid with a minimum of fuss, and no danger to the tree.

That said, there’s another issue that puts a perplexing twist on the whole notion of pavements and trees. Apparently, mature trees can be obstacles in and of themselves. That tree in the top photo? It’s been designated as an obstacle on the pavement, and is set for removal.

A notice on the tree lists 5 possible reasons for removal, and a tick mark next to the one that says ‘the tree has outgrown the location and is excessively damaging or obstructing the footway’.

So here’s a healthy, structurally sound tree that is not damaging private property, yet is scheduled for removal. There’s no visible evidence that the tree is damaging the pavement: the newly-laid tarmac is smooth and level. Nor is there evidence that the tree is an obstruction: the footpath is wide enough for two people to pass; wide enough for a wheelchair, pushchair, or trolley.

I am not convinced there’s a reasonable basis for removing the tree, particularly given the various types of value it produces. The tree is in good health, is providing a significant amenity, plus contributing to habitat. ecological and city health.

Like the method used on the River Rea cycle path, it looks like an extreme reaction to a minor problem. With that in mind, I wondered if any other English local authorities take a different approach. A short search turned up a pretty good example in the London borough of Hounslow, where the council website has a nice explanation of the general approach. (Incidentally, there’s also a nice dynamic map of scheduled street works. Would that we had the same here… .)

Two point arise out of this puzzle. One is that I am not convinced this tree warrants removing. The other is that the explanation doesn’t give enough explanation. One or both of these things point to something wrong, somewhere.

I do not believe there’s such a thing as a tree ‘too big’ for the street. More likely, I guess, is that where there is competition between say, parking space and tree preservation, the tree loses. And the city loses.