When I was a young arborist I did terrible things. Terrible, arboricultural things – I’ll keep this professional and not a self-indulgent personal narrative (I’ll save that until I am old and want to embarrass my children). When I was a young arborist I did terrible things, but at the time they were considered best practice, cutting edge even.

When I started teaching, I taught terrible things (I may have been a terrible teacher too – but that is another story). When I started teaching, I taught terrible things but at the time they were considered best practice, cutting edge even.

The textbook that was the bases of my initial arboricultural training was written in 1976. When it was issued to me 12 years later it was still considered best practice. When I started teaching 12 years after that, much of it was still considered best practice, although no one would have called it cutting edge. The photographs had dated, and we had moved away from flush-cutting, but the rest was ‘solid’.

When I stopped teaching 12 years later things had moved on, but most of the advancements were around in health and safety and climbing. That side if arboriculture had taken massive leaps forward, but apart from rejecting flush-cutting and pruning paint, pruning practices hadn’t really changed since 1976.

The terrible things [to trees] that I did were all done with good intention, they were considered best practice at the time. I had always worked for progressive tree care companies and I don’t feel bad about doing what we did, but we shouldn’t do them now… that would be terrible.

So, what are these terrible things that we shouldn’t do? Putting my personal narrative to one side, we need to stop ‘thinning’ and ‘cleaning out’ our trees for a start – we have effectively been gutting trees for over 30 years and gutless trees don’t survive. Recently a storm event passed through my hometown and almost every park tree that failed had been repetitively thinned. Those trees that didn’t fall over had nothing left to prune the broken bits back to, so they might as well have fallen over anyway.

We have to stop removing every bit of dead-wood – yes, remove or reduce the hazardous bits, but what lives in the dead-wood is important. What lives in the dead-wood probably doesn’t harm the tree, and what lives off the things living in the dead-wood may well benefit the tree.

We need to stop pretending that what we do is ‘natural’ – it is not natural for a tree to grow surrounded by concrete, glass and steel. Our trees are growing in a manufactured environment and need to be managed accordingly.

We need to stop applying one set of rules to every situation – standards are great, but sometimes half a tree is better than no tree at all, sometimes a bad pruning cut or no pruning cut at all, might be the best thing to do.

We need to prune our trees as part of an on-going management programme and we need to commit to that management programme not just for three or four years, but three of four lifetimes.

We need to accept that we might have been doing terrible things to our trees, even if our intentions were good and our actions were considered best practice.

And lastly, we need to consider how we prune and base what we do on science. If the reason you do what you do is because that’s the way it has always been done, then maybe you need to think again.