Tree surgeon

This guy is fastened near the top of what was, until this morning, a 45 feet-tall ash tree, which he is cutting down. This is a highly skilled and very dangerous job.
Why is a fine tree being cut down? It is dead - having been deliberately drilled and poisoned by a malicious person who actually is a neighbour of my piano teacher ( who is a kind and gentle man). The malefactor was discovered crouched in the garden late one evening armed with a drill and a bottle of glycophosphate. He achieved his objective, for nine months later the tree to which he had taken a totally irrational dislike had died. A great shame, for it was a beautiful 50 year old tree, well away from dwellings, and totally harmless.
Taking a tall tree down is vastly expensive, as one might imagine.
The saga has some way to go yet.........!!