alt Hacker NewsTrees "calculate" which branches to drop based on data they gather as they grow. A competent and experienced arborist knows how to read the tree and simply safely cut off the branches that the tree was already intending to drop so that it doesn't fall on your house or whatever. Inexperienced arborists often ignore this key dendrology fact and may totally butcher your tree. In the process they can create an even larger risk of a tree falling over onto your house during a storm
It's called cladoptosis (basically self-pruning) https://en.wikipedia.org/wiki/Cladoptosis
EDIT: since I'm on the topic of bad tree trimming, NEVER TOP YOUR TREES https://www.arborday.org/tree-resources/dont-top-trees
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>NEVER TOP YOUR TREES
they do it where I live because the branches bang against apartments' windows when it's windy. I don't think there's another low-maintenance solution.
Fascinating! Where is this data stored? I love the idea of a Tree DB queried via TreeSQL.
>NEVER TOP YOUR TREES
Kind of annoying when all the fruit is several meters out of reach
I'd like to grow bonzai. I have zero prior knowledge. I suppose what you mention applies. Would you happen to have any good resource that applies to bonzai science please?
I'm an arborist since 2022 in the UK and yes, never top trees. But...
There's three scenarios that come to mind in which it's somewhere between "acceptable" and "totally fine for some reason".
One, it's conifer hedge (the types popular in the UK) as these typically respond very well to being topped. It's what makes them a nice tidy hedge. I'm specifically referring to hedges above 3 meters in height. If you ever worked a hedge like this you'll quickly realise the topped stems are the platform to work off. These hedges can be maintained like this for years. For some reason, topped hedges are completely fine with being topped.
Two, it's either topping or removing. Arguably neither is ideal, but some retention is better than no retention. Topping puts the tree on senescence pathway and gives the ecology time to transition from alive to dead and dying. Whereas removal just makes the local fauna get confused about where the tree went.
Three, veteranisation in woodland settings. If there's a distinct lack of standing deadwood and age variation in a population of species in a given woodland NVC type, the topping and verteranising could be a positive management approach on a sample of trees.
This advice is very specific to the UK and especially on point three to the NVC woodland types. Generally though, prune properly at the correct locations, using proper technique being mindful of the structural loads and balancing of the tree. Topping generally, "because reasons" isn't an ideal approach at all.