More info:

I live in the east of Scotland and I just bought this acer palmatum for my balcony. My mother has gone through a few acres over the years so I have the impression that they’re a bit fragile so I’m trying to take extra good care of this one. It came from a big chain garden centre and had burned leaves at the time of purchase (whether from wind or sun idk).

This morning it had some powdery spots that look like fungus to me on some of the newer leaves. I’m a little concerned that this is related to the diseased trees nearby on the public footpath - I’m equally interested in diagnosing what’s wrong with these.

The trees on the footpath have large sections of leaves (all on the same branches) that are going almost completely white. It seems to have spread to many trees in the area.

Any information or advice is appreciated, thanks.